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3124996 ��aim�i j Engineering — Planning- Surveying Commercial — Residential — Public Works Telephone: 760.360.4200 / Fax: 760.360.4204 AMENDED 100YEAR HYDROLOGY REPORT AND RETENTION BASIN DESIGN Prepared For: ADOBE MOLDINGS, LLC TRACT 31249 VILLAGE AT CORAL MOUNTAIN In the City of La Quinta, California In the NE 1/4 NW 1/4 of Section 28, T. 6S, R. 7E S an B emardino Base Meridian JULY 27, 2006 David Me, RCE NO.: 35728 EXPI S: 6-30-07 o Q ROF ESSIp,y R�C�, No. 35726 -A Exp. olso �6 -7 sl CiV11. �OF CAL W 9 Obt ;,%Oo Ong, EE '1 -ftJ9lUlOd 4�� u .."Lveszg 7o"S' "k L ; 4, � f � f'T'F'2i� � _ Y.` 1 T j .� I! # 1. - Mme' Z .. :S "e :4 Y iMf '�� ~'L 5 �' ,r 2 R h - . { A, ih � C�S��' S' f[: ' "N 'v 4, MR1 Od " - — - -!V .. , . . — . .1 , V ;ow igpv ''�i ,�f' � A-? � ,r r A ' �b'�4r -"�x�' �v��`4 �St'+�,- `�S ' _a -,�s 3� y.+ f ,. r� - '� .1 i y� x "I Z _42 F ffn 02 3 ME Sm ME M I- alr I 011 'MA EHLINE July 17, 2006 AVENUE 58, WEST OF MADISON THE VILLAGE AT CORAL MOUNTAIN HYDROLOGY AND DRAINAGE FACILITY DESIGN REPORT INDEX Cover Sheet P. 1 Index p. 2 Hydrology and Drainage Facility Design Report p.3 -5 Location Map — Predevelopment p.6 Drainage Area Map — Post Development p.7 Soil Conservation Service Aerial Map p.8 Retention Basin Storage Summary p.9 Catch Basin Summary p.10 -11 Catch Basin Width Design p.12 Data Appendix 1. Soil Engineer Geotechnical Report p.A1.1 2. Retention Basin Design Procedure p.A2.1 -2.2 3. Storage Hydrograph Calculation Spread Sheets p.A3.1 -3.30 4. CVE Design Calculations p.A4.1 -4.8 a. Catch Basin Design Flows p.A4.1 -4.10 b. Street Capacity Drawing p.A4.11 c. Street Capacity Calculations p.A4.12 -4.18 d. HGL Calculations p.A4.19 -4.29 ' Retention Basin Report Text 060717.doc * *REVISED 7- 27 -06 ** u AMENDED FOR 100 YEAR STORM HYDROLOGY REPORT And RETENTION BASIN DESIGN For TRACT 31249 -1 Adobe Holdings, LLC ADOBE HOLDINGS, LLC CVE JN 06122 ' Coachella Valley Engineers is pleased to present the following report to the City La Quinta, California. The report includes computations and exhibits for the design of storm water management facilities for the subject property. ' The purpose of this amended report is to analyze the proposed storm water runoff characteristics of the referenced site and its immediate surroundings for the 100 year storm occurrence cycle and not the 10 year as presently is the policy. The initial Hydrology Report and Retention Basin Design was modified by the City of La Quinta and agreed to by the developer, Robert Rippey of Adobe Holdings, Ilc. The scope of this report is to evaluate the pre - development and post - development condition of the site and to determine the required storm runoff management necessary to dispose of onsite runoff and avoid blockage or increase of offsite runoff through subject site. This proposed storm water management plan describes the procedure for controlling storm water runoff for the purpose of preventing downstream flooding. The method of preventing downstream flooding is the use of retention basins to impound the runoff and dispose of it via percolation. The site has been designed to retain all storm runoff from the site and from the south half of Avenue 58 adjacent to the site. The proposed retention storage is more than adequate and is fail safe in design. SUMMARY AND DISCUSSION INTRODUCTION AND PROJECT INFORMATION The site is located along the south side of Avenue 58, '/2 mile west of Madison Street, at the edge of PGA West and a County Park. The site consists of 35 acres of sandy, hummocky and slightly rolling land to be divided into 85 residential lots of approximately 10,000 to 17,000 sq. ft. each, and common areas containing five landscaped retention basins. Historical drainage in the project area is from west to east. (See the enclosed Pre - Project drainage map excerpted from the USGS quad sheets). The surrounding area south of Ave 58 is now Vacant, hummocky sand, and probably has little or no runoff due to the high percolation rate of the sand and lack of any impervious area.. • West: The offsite property to the west is vacant sand and light desert brush, and is designated as a ' county park. When the park is developed, all rainfall will be disposed of within the park property, and will not contribute to flows to subject property or Ave 58. There is no present drainage from the west into subject site. At some time in the last 50 years, the ' adjacent property to the west constructed a 45 -foot wide by 3 to 5 foot high berm west of the property line, which stops any drainage from the west. This same offsite property also constructed a dirt road , ' Page 1 of 4 ' Retention Basin Report Text 060717.doc ADOBE HOLDINGS, LLC * *REVISED 7- 27 -06 ** CVE JN 06122 ' which slopes north to Ave 58 along the west toe of the berm. (See the contours along the west edge of subject Site Grading Plan). ' Subject Site Grading Plan proposes raising the finish grade along this west property line to minimize elevation differences, and construction of a 6 -foot high property line wall. ' Ave 58: Rain falling within the Ave 58 right -of -Way flows from west to east along Ave 58 past subject site frontage. Ave 58 is several feet lower than subject site, and no street flow enters subject site now. Subject development proposes intercepting any drainage along the south half of Ave 58 and disposing of ' it in the onsite retention basins. South and East: There is no present drainage.from the south or east into subject site. The properties ' to the south and east are very hummocky with random sand piles. It is very doubtful that there is any runoff from these areas. Any runoff would flow south and east away from subject site. When these properties are developed, they will be required to dispose of all drainage onsite. ' Therefore, subject site only receives offsite drainage from Ave 58. HYDROLOGY ' The Riverside County Flood Control District has approved the Rational method as a simplified procedure for calculating approximate storm water runoff characteristics and flow rates for drainage areas not exceeding 300 to 500 acres in total area. ' The Drainage area map sketch included with this report for orientation purposes indicates the major features of the proposed Storm Runoff Management Plan (SRMP) for subject property. Refer to the project Rough Grading Plans for detailed features of the SRMP. ' Sladden Engineering performed a percolation test on the site. (Project No. 544 -3272 — Dated Sept 11, 2003). The test results were 6.6 and 10.8 inches per hour. Per City requirements, the default percolation value of 2.0 inches per hour was used as the design percolation rate. ' The Hydrology for Subject property and design of the retention basins is developed per the requirements of the City of La Quinta and the Riverside County Hydrology Manual (RCHM). (See attached enclosures). ' The hydrologic soils group map for La Quinta is included in the appendix of this report. The soil classification for this site is type "B ", having moderate infiltration rates, antecedent moistening condition ' rating of AMC II, and moderate runoff potential when saturated. The site Runoff Index was determined to be RC 56 for residential landscaping on Group B soils with 50% impervious cover from RCHM plate D -5.5. ' The storm volumes of 2.1, 2.7, and 4.5 inches for the duration of the 100 year -3 hr, 6 hr and 24 hr design storms respectively, were interpolated from plates F -5.2, F 5.4, and F 5.6 of the RCHM respectively. ' The data for each design storm is listed in segments /intervals for calculation of results that can be plotted as a retention volume vs. time hydrograph. Fifteen - minute intervals were chosen for the. shorter storms to provide enough data points to generate a smooth curve. ' The Rainfall Intensity in % of total storm volume for each segment/calculation period was taken from plate E -5.9 of the RCHM and is shown as "Precip %" in column 3 on page 2 of each calculation. The Rainfall intensity in in /hr was then calculated for each interval. ' The storm runoff inflow volume was calculated for each interval. The percolation volume was calculated for each interval using only the water surface area of the retention basin during that interval The percolation volume was subtracted from the storm runoff inflow volume to determine the required ' retention, depth and water surface area for each interval, and the peak required retention. (See attached calculation result spread sheets.) ' Page 2 of 4 ' Retention Basin Report Text 060717.doc ADOBE HOLDINGS, LLC * *REVISED 7- 27 -06 ** CVE JN 06122 ' Subject Drainage Management Plan utilizes five retention basins. The tributary areas for basins D and E include Ave 58 and the Tract entrances. The tributary area for basins A, B, and C include the remainder of the site lots, common areas, and onsite streets ' The 100 year storm event requiring the most retention was used for design of the retention basins. Retention basins A, B & C will utilize the newly adopted type of deep well percolation chamber for ' the disposal of all retention storm waters into the sub surface aquifer and into the water table. ' The onsite elevations have been designed to allow emergency storm overflow of all retention basins to the northeast corner of the site, thence into Ave 58, and thence east along Avenue 58 without flooding of any building pad. ' Three large retention basins (A, B, C) have been-placed in the large, U shaped, landscaped common area in the center of the site. These basins are sized to retain the design storm without exceeding 2.0 feet depth of water. Each basin is less than an acre in surface area. The bottom of these basins varies ' from elevation 459 to 465.5, creating emergency retention varying from 2.75 to 3.6 feet deep. This extra depth should retain the maximum possible storm for the site without outflow and without flooding any structures. ' Basin A: The north -east 1/3 of the site drains to Basin A. Basin A will have a normal maximum water surface at elevation 460.47 (0.5 foot below the depressed gutter at the lowest curb inlet/catch basin), and will overflow to the north -east to Ave 58 along the Coral Mountain Court gutter between Lots 37 and 38 at elevation 462.21. All pad elevations in the Basin A drainage area are above elevation 464.5 creating over 4.0 feet of freeboard below the lowest finished floor. Basin B: The west side of the site drains to Basin B. Basin B will have a normal maximum water surface at elevation 467.23 (0.5 foot below the depressed gutter at the lowest curb inlet/catch basin), and will overflow to the east to Basin A through the landscaped common area between Lots 47 and 59 at elevation 468.48. All pad elevations in the Basin B drainage area are above elevation 470.00, creating 1.0 feet of freeboard below the lowest finished floor. Basin C: The south side of the site drains to Basin C. Basin C will have a normal maximum water surface at elevation 461.78 (0.5 foot below the depressed gutter at the lowest curb inlet/catch basin), and will overflow to the north along the Coral Mountain Court gutter between Lots 32 and 69 to Basin A at elevation 464.15. All pad elevations in the Basin C drainage area are above elevation 465.1, creating 1.0 feet of freeboard below the lowest finished floor. Basin D & E: Two small retention basin systems have been placed at the main entry streets to dispose of runoff from Avenue 58 at the entry points. These basins are approximately 6000 sq. ft. in surface area, with less than 2.0 feet of storage depth required for the design storm. The proposed retention storage is far more than adequate, and is fail safe in design. Hydraulic Design The 100 -year, 1 hour storm event was used for the street capacity confirmation and design of storm drain pipes. The 10 -year storm event was used to design the catch basin widths. Criteria for Rational Method design of storm drain inlets and piping were derived by calculating the initial time of concentration for rainfall to begin to run off from the farthest corner of the farthest lot; the travel time to flow from the back of the lot to the street, and the travel time to flow in the street from the farthest lot to the storm drain inlet (See RCHM plates D -3 and D -7.7 attached) Page 3 of 4 Retention Basin Report Tent 060717.doc * *REVISED 7- 27 -06 ** ADOBE HOLDINGS, LLC CVE JN 06122 This total time of concentration is ranged from 8.83 minutes to 16.46 minutes and yields design intensities for 10 year storms of 3.05 to 2.12 inches /hour and 100 year -1 hr storms of 4.47 to 2.12 inches /hour respectively. (See RCHM plate D -4.1) Page 4 of 4 IN THE CITY OF LA QUINTA, CALIFORNIA VICINITY MAP FOR TRACT 31249 IN THE NE 1/4 OF SECTION 28 T 6 S, R 7 E, SBM ' N Z O N w w w w -' 54TH AVENUE Amy LA QUINTA o U U) Z O Ln a SITE v AIRPORT BLVD 58 AVENUE (56TH AVE) VICINITY MAP a s . CORAL MT. Cf CAHUIl1A STONE CREDO _ �0 Q10 0.79ds 4t 4t 0 BASIN D �a SD '8 -0 18' •r �• WS ELEV,00= 467.26 4 3035E 0 �_ - - . - - -- -- (475) _ ----- - - - - -- 0.56 RES v 341 CB -70 0\ 35 ;;; ACRSOES S TC 48387 too = 4.5 ACRES G 474.50 4,593 S\Q FT. ° 010 - TB 478.00----4 , \ 34 n 6' BLOCK WALL 0.07 RES .335 ACRES � 42ds 411, 5 F 44 z 4,a566 ES FT' (PROPOS ) 40 38100 = +� - 0.71dNsTION /LANDSCAPE BASIN E SD A -off' 18 / A PE 474.50 0100 - 2 -2Mps / 0.163 SO. EFl. 33 39 PE 464.00 , H' ELEV,� 459.99 5,638SF /4/ E 470.10 41 PE x65.60 , 1 PE - 222fpa / 46 45 ' 43 PE 468.00 PE 466.90 >\I PE 464.70 ` wSroal+ao.00)= 5,6385E wsaor(4ae<oo) =1,931SF Lf) 4 PE 469.10 1 h D 'G' 18' i PE x74.50 PE 471.30 E 471.10 I 1 0w FLOW Q100 - , 470. _ -__ - -- - - - - -- - - - - -- V"D = 2.81 fps HP I Co PE 474.50 1 , 3 '+0 I --'- 38 ``` (�' I , ' 3I 14 PE 474.50 `� , / --- . 37 3.571 So. ' \ 1\ - _ - PE 464.00 ' 0.08 ACRES EXISTING 45'x3'-/ i ' i 457 SO. FT. PE 473.00 `�`� , r 46 194 SO. FT. - --� -� L f. , I 60,124 S0. FT � 18 ACRES 1. ACRES � D Otoo - 9.08ds 010 - 3.SScf , BERM , , •2 `FT: �7 t 1O+CO 5.974 AGE SO 'D' 30' I i I � 5 ; HP 9 50 52 Qloo f9 t 100 - 15. 47 48 PE 468.90 PE 467.60. PE 466.20 PE 465.00 100 I % ; 841 S0. -g E a7o.ao/ PE 470.20 SO ' 42' 1 , TC 482 30 ; VACANT M=/BRUSH I PE 474.00 ' 47 ACRES ,p , ' I 2 TC 489.1 - OtoO - 03ds i FL 481.47 - 1 PE 474.0 FL 468. 1 7 I 53 36 VACANT' P , , 8 , It PE 0,09 AC O• PE 464.5 Ciw ' PE 464.00 I i • s I ELEV,ao= 460.47 zz.7o2sF O1� �� 35 i 32' PE 473.50 � 4, `�\ - 3. s 7- ,- ..47) =22.809SF h < ' .'�. ' G 474.00 \ \ z P H.P. ao� ' K'� '27' E x64.50 , �� . I RAW C, L R W 1 .1�.81ds , �, 1 i ( ) 0.57 - 4.43fpY85 8 115' SO. FT. 54 5; 1 �i�' 1 �� ! 10' I 16' 16' 10' I� %�' O 1 81.908 SO. FT. , ' II ' i ; : PE 473.00 2.6 AC 8 PE 567.50 'PE 463.30 1 1 , llyw.l r 2% 2Z, • 2% , � 55 1.88 ACRES 2PUE I PUE 9 ,a 60 ,56 PE 466.00 �� 34. ; i I PE 473.30 i ,59 PE 468.50 PE 466.60 � ' PE 46500 i 84 PE 471.2 PE 470.00 53-335 SO. - - -- _ - -' -- `----'----- , ' i EXISTING i f PE 474.00 �= o o^ 2 t•� ACRES ' ( 6 WEDGE CURB & GUTTER ` , }� 10 ' _ _ ' , TYP DRAINAGE % 8: /- n 1 �� " ------ - - - - -_ 33 I PE 473.90 ' i - -�•• -- _-- -- I , �V h' PE 465.50 1 1,6?i _' ad �" 61 _-- " - - - -- 11 ' (E) Y W i INTERIOR STREET ' , - ----- - c O , 0. 83 s� PE 471.70 = ,05.1 0. PRIVATE STREET 11 i Tn E 475.00 °� ', '� 51,680 SO. .i 6 E � 1 J° i I PE 475.50 ; ; v°i� -� ' 1.�9 ACRES 6 PE 466.00 PE 465'3 dW ; �� I ;' STREET AREAS - 8.05sf I 5 PE 466.60 O i 32 ; ,�f� o , 62 Yn�,, 4 PE 487.50 � PE 465.60 ; � 1010 WETTED PERIMETER - 32.331f 82 284 S 1 Y O E 82,00 471.20 PE 468.50 1 toe, s so. FT. 3 ; 1/2 STREET AREA - 2.21 sf 1 CV 2.50 RES 470.90 I i t (. 1, ' 12 i HP PE 470.00 69 3 I FLOW ' 1 WETTED PERIMETER - 15.601f It 476.00 PE 465.1 PE , �j ' I 1 ; J NTION /LANDSCAPE BASIN C .rQ WS ELEV,00= 461.78 27,700SF 81 Ws,ov(4nw) =28,324SF WS90T(4a&oo) =22,730SF AVENUE 58 13 ; PE 477.00 180 92 SO. FT's 4. ACRES HP 70 owi '� OFFSRE o , �� , ' I 3e W 13 ; , 25 PE 465.1 I 30 1 ; DRAINAGE 1 /2 STREET AREA - 7.76sf U ' O 9 PE 476.50 I 00 i () 16 (485) ` PE I \ f N N_ 14 % PE 478.00 HP ' 1 , I , I CD •M , PE 465.40 I I BOUNDARY W WETTED P PERIMETER - 55.91 If otoo - 477.00 79 78 7600 PE 47`11.00 74 •73 V72 E77oo PE PE 478.00 PE 475.00 PE 469.50 pE 468.40 PE 467 1 2 68.590 SC FT. _ _] SZACS __-- -- -- •M , PE 465.40 I I BOUNDARY W WETTED P PERIMETER - 55.91 If Cu ; .� ,I .� SF - SAND FILTER - - - - -- _ _ - - -- ---- - - - - -- - ---- - - - - -- - - -Te-� i - - - - -- ----------- - \ ' - - - -- - - - - -- - -- ------ - - - - -- Ft 463.11 - - - - - -- `� � "6,l �) - HIGH POINT , -- - - -- -- ---- -- -- E EXISTING 0) ; 15 16 17 Cpl 18 9 164.992 rs. Fr. 23 �E) 26 28 LP - LOW POINT 1 I p€ 480.00 PE 478.00 �� 3 I T PE 476.50 20 3.79 ACR 22 24 25 PE 466.10 �., PE 479.00 PE 474.50 pE 473.10 P 469.70 PE 466.00 27 ' F - FLOW LINE BLOCK WALL PE 466.40 pE 467.20 PE 466.00 �- DRAINAGE AREA N0. I I PE 470.80 Q TB 489.00 G �• ROPOSED 22 0 c 73.00 ' 1 Nc ;8200 ®- DRAINAGE LIMITS 1 GRAPHIC SCALE - -- - - - -- - - --- -_ - --� -- __ - --- ----------- - - - - -- --- - - - - -- ti '', BERM _ _ G 474.00 I DRAINAGE AREA MAP 0 70 140 1 , __ - 1 ----- -- --- - -- _ a STORM DRAIN /RETENTION BASIN EXHIBIT ( IN FEET) \ �o� -, ^ i TRACT 31249 -1 \ I , ` h 40 I .. MADISON 58 PARTNERS 1 inch = 140 ft. I 'I9s `' �" AND ADJACENT SITES I I' I y�. :RU \, ny.: ?t'•_c •.�= _ ....a-: ^�1r� -;�,-' - ¢' a 1,1.1:!1 te r ;�1'•'.•t'�i':,I:: I. M �� y..�. ` a!!;Ita%'.•',L 111�i 1 w 1p a . $::.a -• -. • i �:;: ^,fit„_::' " o .; • •W= IL'!:'!i�'I i:Ti;11: i. : - •v�;:` ��,.:.,; ;Aar'. =i•:. I CSA .�:•I. '1 .. Qu;J. T''�• -fit.. �� Gt Gt vv 6:,x_ Is tea\ RO =r I.�` . z ,_�• - '.:�-y,� ��' _3 _ r� � - - �.• ' :�• :Y " - "�:: �� _ is _ RU 71. - �%a• la�ac cr,' ':'C: - AVEhpAU' SF .�- "� •xW j`, _ _ .•E.c; ;i7- ,er•,y., ; ?.: ill •1•I I� .t" Y°i• _ _ �, iii:= e:i,.. ••'i'i�: %W _ K -tu RU'- =a�? CdC =_ -.;, Is' W zn �..:. c: Gb i•' •:1.• I.' A �; : t•' ._.: >`s•• •�f 's \.. - �i�st+ �-'; _ � :'nP�� _yt` �r^'F'�•° %SG eA t� "'y �: p �•„ .. ry �t RQ r r �.' esas • it �. - :..I; Jai RU \ �..`h✓g, ;e I »_ �T'• si i•.: '•�� {.�si {. � ' /: ::: •a- :J�' -�ar�" RU _ _`.b•�•c -_ »:>3��'4;; '' �'� I_P. � E"�:,.�f__�'f`5 =^.a! `y�•'.._C ccc J. U. ,�,ma�yy f� A= •e •� �'a .:.v �•�h�a: ?i +- \ +`�' �NiA'! =,`•.^ '1�� -. "n.. •lv-.. � �°Ci�1 � .'�1L,ja ,, S..`•'c':..i./ •�.. .:y a 6ilir� I I �S' • _ :per.. '` - 'j' ,r vali� ' '�' n,`• s`Ey +, �.. \ ' ;?l` m. Itr� ;� ,y G ,,: :, P . •'•,ate ' r�;- 1 . ",`'•�:- •t�- '= �',.r.: Y ...�-.:'�.••�:RA .,a.,•i.a a _Ti`•: s�.,. -._ •'GC A'O�C(iQ :.. l is := _.:f:ri ''• "- CcC' �...�_ S 'i410 <: %��.i _ •: �.,... - - G CdC. CdC C A PA CcC MaB GP all CdC �/ �/ "� ©1 / 1/i 1! C$A n GcA pfd 1NN ':1 _ ..�,•�/7 - f- ` / 1 �• 11 O� ROr GaB is IylaB J, CdC :'as..'; p r _ _ _ i� CcC �• / /C RU / T_kB1.,E 12. —Soil and water f eatures ;ence of an entry indicates the feature is not a concern. See test less descriptions ns of enr than] and such terms as tra e�„ "brief," and "perched,." The symbol G means less than P Hydro- Flooding High water table Bedrock Soil name and logic map symbol group Frequency Duration - Months Depth hind Months Depth Hard Ft rn t f 1 - None------ -------------------------- None------ -------------------------- None------ ---------------7---------- Rare------- -------------------------- None------ -------------------------- None-------------------------------- None------ -------------------------- None------ -------------------------- None------ -------------------------- None------ -------------------------- Frequent --- Very long_____ Apr-Sep---- Occasional__ Very brief____ Jaa- Dec___ - Rare- - - - --- -------- - - - - -- ------ - - - - -- None------ -- -- ------- --------- - - ---- None______ None______ None______ None ------ None______ None______ None______ >6.0 ' Badland: BA. >60 Borrow pits: -------------------- - - - - -- Bull Trail: >6.0 BtE----- ------ - - - - -. B ' Cajon: >6.0 ---------------- Cajon Variant: • >60 CbD----------- - - - - -- A i Ca .-.. rnzo: CcC---- .------- - - - - -- A 2.0 -4.0 Cd E, C hC, C k 8. ZF8------------------ A ' Carsitas Variant: Cm8, CmE ----------- Chuckawalla: Co B, Co D, CnC, Cn E. C B -------- - - - - -- 4 C C A r -l---------------- Rippable. Fluvaquents : Fa------------- - - - - -- D - - - - -- Fluvents: . Fe------------- - - -- -- ADD >6.0 G ilma GaEZ Gb B, GeA. GcA, A, GFA______ � -BB >60 Gravel pits and dumps: G P. 3.0-5.0 ' Imperial: IeA------------ - - - - -- IfA------------------ D D __________ ImC 1: Imperial part_______ Gullied land part. D ' Impperial: IoCI: Imperial part_______ Gullied land part. -. - -- D 1 IIs ---------------- ?Al P,� --- - - - - -- >60 > 6.0 ----- --- ------------ Litbic Torripsamments: L Li Lithic > 60 ---- - - - - -- Torripsamments part. Rock-'Outcrop part. D t f 1 - None------ -------------------------- None------ -------------------------- None------ ---------------7---------- Rare------- -------------------------- None------ -------------------------- None-------------------------------- None------ -------------------------- None------ -------------------------- None------ -------------------------- None------ -------------------------- Frequent --- Very long_____ Apr-Sep---- Occasional__ Very brief____ Jaa- Dec___ - Rare- - - - --- -------- - - - - -- ------ - - - - -- None------ -- -- ------- --------- - - ---- None______ None______ None______ None ------ None______ None______ None______ >6.0 -------- - - - - -- ------ - - - - -- >60 >6.0 -------------------- - - - - -- >60 >6.0 -------------------- - - - - -- >60 >6.0 ---------------- ---- - - - - -- • >60 >6.0 -------------------------- >60 ---- 2.0 -4.0 Apparent----- Jan - Dec____ >60 - - - --- ---------- >6.0 -------- - - - - -- ------ - - -- -- 6-20 Rippable. >6.0 ------ -- ------------ - - - - -- >60 _ _ >6.0 _ ------------- ----- - -- - - -- >60 ---------- 3.0-5.0 Apparent____- Jan - Dec_ -:_ >60 __________ 0.5 -3.0 Apparent -___- Jan- Dec ---- >60 ---------- >6.0 - ------- -- ------- --- - - - - -- >60 ---- - - - - -- > 6.0 ----- --- ------------ - - - - -- > 60 ---- - - - - -- 3.0-5.0 Apparent___ Apr- Oct____ >60 ---------- >6.0 _ 1.0 -3.0 Apparent_____ >6.0 -------- - - - - -- 1.5-5.0 Apparent -__' -_ >6.0 _ 3.0 -5.0 Apparent_____ >6.0 >60 ---------- Jan- Dec____ >60 _ ------ - - - - -- >60 ---------- Jan-Dec---- >60 ---- -- ---- >60 ---- - - - - -- Jan -Dec - -- >60 ---- - - - - -- i �I ------ - - - - -- 1 -10 Hard• C ve 0� .22 6. l � III ■� ■� I� � IIIII� IIII� III I� I� IIIII� IIIII� III III � I� IIIII� IIII� RETENTION BASIN DESIGN SUMMARY FOR 100 YEAR STORMS PREPARED BY COACHELLA VALLEY ENGINEERS BY: DATE: JOB # REF: DLC 13- Jul -06 2226 Ehline -Tract 31249 - Ave 58 / Coral Mt Court Retention Basins A B C D I E Tributary Areas No. Area No. Area No. Area No. Area No. Area (SF) (SF) (SF) (SF) (SF) 1 51,680 11 82,284 21 164,992 31 24 373 32 14,550 2 53,335 12 43,136 22 68,590 33 7,094 35 51,177 3 12,562 13 60,124 23 49,078 34 14,593 36 6,695 4 81,908 14 50,457 24 10,336 37 3,164 5 14,815 15 20,641 25 180,392 38 3,571 6 124,856 16 18,165 7 46,194 17 3,738 8* 8 18 108 990 Ac s Ac s Ac s Ac s Ac s TOTALS 8.847 385,358 8.897 387,535 10.867 473,388 1.057 46,060 1.817 79,157 RETENTION BASIN DATA Water D ft Vol cf D ft Vol (cf) D ft Vol (cf)' D ft Vol cf D ft Vol cf 3 Hr 2.81 39671 1.40 28848 1.33 31978 1.26 4045 2744 1.71 5626 6 Hr 3.07 44519 1.32 26130 1.32 31659 0.96 1.81 6054 24 Hr 3.97 60491 1.73 32522 1.78 40491 1.10 2833 1.99 6250 CONTROL ELEVATIONS Lowest PE LOT 53 464.50 LOT 47 470.80 LOT 69/70 465.10 LOT 46 471.30 LOT 37/38 464.00. Overflow 462.30 469.13 463.87 469.17 461.25 Max WS 22702 460.47 24137 467.23 27700 461.78 4303 467.26 5638 459.99 Bottom 456.50 465.50 460.00 1466.00, 1 458.00 CATCH BASIN SUMMARY' PREPARED BY COACHELLA VALLEY ENGINEERS BY: DLC DATE: 29- Jul -06 JOB # 2226 REF: Ehline -Tract 31249 - Ave 58 / Coral Mt Court CATCH BASIN 1 2 5 4 3 0 7 DRAINAGE AREA CB Q10 Q100 PIPE DIA. SLOPE Q100 AREAS TO (sf) WIDTH cfs ) (cfs) IN in ft/ft cfs 36 6,695 4 0.42 0.71 N/A N/A 38 3,571 10,266 37 3,164 4 0.13 0.22 "F" 18 0.71 6 124,856 4 5.41 9.09 N/A N/A 4 81,908 4 3.55 5.97 "E" 30 0.005 9.09 1 51,680 6 7.74 13.01 "D" 30 0.007 15.06 2 53,335 3 12,562 5 14,815' 7 46,194 178,586 11 82,284 6 8.88 15.04 N/A N/A 13 60,124 14 50,457 15 20,641 16 18,165 _ 231,671 12 43,136 4 1.8 3.04 "A" 27 0.005 15.04 17 3,738 46,874 PIPE OUT "F-1 „G„ "E" DIA. SLOPE Q100 Top TO (in) (ft/ft) (cfs) Curb HGL RB Ws100 18 0.005 0.71 461.21 460.00 18 0.12 0.93 461.21 460.00 "E" 459.99 9.09 462.02 461.06 30 0.007 15.06 462.02 460.98 42 0.032 28.07 462.27 460.74 "A" 460.47 "A" 27 0.005 15.04 468.93 467.92 "B" 27 0.106 18.08 468.93 467.59 "B" 467.23 IIII� IIIII� �. Illllllllls IIIII� IIII� II. IIIII� IIII� IIII� III. IIII� III. IIII� IIII� IIIII� IIIII� IIIII� IIII� CATCH BASIN SUMMARY PREPARED BY COACHELLA VALLEY ENGINEERS BY: CATCH BASINS DLC DATE: 3 7- Jul -06 JOB # E 2226 REF: A Ehline -Tract 31249 - Ave 58 / Coral Mt Court RET. BASIN: CATCH BASINS 1 2 3 4 5 E E A A A No. Area No. Area No. Area No. Area No. Area (SF) (SF) (SF) (SF) (SF) 36 6,695 37 3,164 1 51,680 4 81,908 6 124,856 38 3,571• 17 3,738 2 53,335 24 10,336 14 50,457 3 12,562 15 20,641 5 14,815 16 18,165 7 46,194 (Ac) (sf) (Ac) (sf) (Ac) (sf) (Ac) (sf) (Ac) (sf) TOTALS 0.236 10,266 0.073 1 3,164 1 4.100 178,586 1178,5861- 1.880 181,9081 2.866 124,856 RET. BASIN: CATCH BASINS 6 7 8 9 10 B B C C D No. Area No. Area No. Area No. Area No. Area (SF) (SF) (SF) (SF) (SF) 11 82,284 12 43,136 21 164,992 22 68,590 31 24,373 13 60,124 17 3,738 23 49,078 24 10,336 14 50,457 15 20,641 16 18,165 (Ac) (sf) (Ac) (sf) (Ac) (sf) (Ac) (sf (Ac) (sf) TOTALS 5.318 231,671 1.076 1 46,874 1 4.914 214,070 1 1.812 178,9261 0.560 24,373 P.10 m m m m m m m r m m m m m m m m m m m RET. BASIN: CATCH BASINS 11 E No. Area No. Area No. Area No. Area No. Area (SF) (SF) (SF) (SF) (SF) 32 14,550 35 51,177 (Ac) (sf) (Ac) (sf) (Ac) (sf) (Ac) I (sf) (Ac) (sf) TOTALS 1.509 65,727 0.000. 0 � 0.000 0 0.000 1 0 0.000 0 P.11 IMI I♦ I♦ I♦ I♦ M M I♦ I♦ m CATCH BASIN 8 10 11 DRAINAGE AREA CB Q10 Q100 PIPE AREAS TO (sf) WIDTH cfs cfs IN 21 164,992 6 8.81 14.82 N/A 23 49,078 214,070 SLOPE Q100 ( ft/ft) (cfs) N/A PIPE SLOPE Q100 TO OUT (ft/ft) (cfs) Tc HGL RB Ws100 "PH.11-B" 24 0.005 14.82 463.98 462.94 22 68,590 4 3.25 5.46 "PH.11-B" 24 0.005 14.82 "PH.11-A" 30 0.021 20.28 463.95 462.40 "C" 461.78 24 10,336 78,926 31 24,373 4 1.26 2.11 N/A 32 14,550 4 2.71 4.56 N/A 35 51,177 65,727 N/A "A -Off Site" 18 0.005 2.11 469.03 467.39 "D" 467.26 N/A "B -Off Site" 18 0.005 4.56 462.65 460.51 "E" 459.99 Sladden Engineering 8782 Stanton Ave., Suite A, Buena Park, CA 90621 (714) 523.0952 Fax (714) 523.1369 39 -725 Garand Ln., Suite G, Palm Desert, CA 92211 (760) 772 -3893 Fax (760) 772.3895 July 8, 2005 Project No. 544 -5526 05 -07 -657 Coachella Valley Engineers 77 -899 Wolf Road, Suite 102 Palm Desert, California 92211 Attention: Ms. Rebecca Jordan Subject: Geotechnical Update Project: Tentative Tract 31249 Avenue 58 West of Madison Street La Quinta, California Ref: Geoleclunical Investigation Report prepared by Sladden Engineering dated August 20, 2003, Project No. 544 -3272, Report No. 03 -08 -544. As requested, we have reviewed the referenced soils report as it relates to the design and construction of the proposed residential development. The project site is located on the south side of Avenue 58 west of Madison Street in the City of U Quinta, California. The referenced previous soils reports include recommendations for the design and construction of the foundations for the proposed residential structures. Based upon our review of the referenced report and our recent site observations, it is our opinion that the recommendations included in the above referenced report remain applicable for the proposed residential development. Footings should extend at least 12 inches beneath lowest adjacent grade. isolated square or rectangular footings at 'least 2 feet square may be designed using an allowable bearing pressure of 1800 pounds per squaw fuot. Continuous footings at least 12 inches wide may be designed using an allowable bearing pressure of 1500 pounds per square foot, Allowable increases of 200 psf for each additional 1 foot of width and 200 psf for each additional 6 inches of depth may be utilized if desired, The maximum allowable bearing pressures should be 2500 psf. The allowable bearing pressures are for dead and frequently applied live loads and may be increased by 1/3 to resist wind, seismic or other transient loading. Z d 'LVD I 5002 b l WOW 1a3S30 W1Vd N30OVIS W08J I� Z XV-i 13[OSVI dH - uv!4t!4S xed WVLO:6 SOOZ Vi Lnr xej paA�- July 8, 2005 -2- Project No. 544 -5526 ' 05 -07 -657 Care should be taken to see that beating soils are not allowed to become satu.ratcd from the ponding of rainwater or irrigation. Drainage from the building area should be rapid and ' complete. The recommendations made in the preceding paragraph are based on the assumption that all 1 footings will be supported by properly compacted soils. Overexcavation and recompacton should be performed as recommended in the referenced report. All grading shall be performed under the testing and inspection of the Soils Engineer or his representative. Prior to the ' placement of concrete, we recommend that the footing excavations be inspected in order to verify that they extend into compacted soil and are free of loose and disturbed materials.. Settlements may result from the anticipated foundation loads. These estimated ultimate ' settlements are calculated to be a maximum of 1 inch when using the recurnmended bearing values. As a practical matter, differential settlements between footings can be assumed as one - half of the total settlement. These elastic settlements are expected to occur during construction. Resistance to lateral loads may be provided by a combination of friction acting at the base of the slabs or foundations and passive earth pressure along the sides of the foundations. A coefficient ' of friction of 0.40 between soil and concrete may be used for dead load forces only. A passive earth pressure of 275 pounds per square foot, per fuut of depth, may be used along the sides of footings which are poured against properly compacted native or approved import soils. ' Retaining walls may be required to accomplish the proposed construction. Cantilever retaining walls may be designed using "active" pressures. Active pressures may be estimated using an t equivalent fluid weight of 35 pcf for native backfill soils with level free- draining backfill conditions. For walls that are restrained, "at rest" pressures should be utilized in design. At rest F pressures unay be estimated using an equivalent fluid weight of 55 pcf. Walls should be provided with adequate drainage. It should be noted that the site is located within a seismically active area of Southern California and it is likely that the proposed structures will experience strong ground shaking as a result of an earthquake event along one_ of the faults in the region during the expected life of the development As a minimum, structures should be designed based upon Seismic Zone 4 design criteria included in the Uniform Building Code (USC). The potential for liquefaction or other geologic /seismic hazards occurring at the site is considered to be negligible. E d 0HOILZ0SVON /16;8 U/D:8 900Z b1 WWI) Sladden Engineering 18IS30 Wldd N30OVIS W08: £ XV3 13M35tlI dH . uo-}e4s xe3 WVLD =6 SOOZ VL tnC Xe3 Pant July 8, zoos -3- Project No. 544 -5526 05 -07 -657 ' In addition, we have reviewed the referenced report as it relates to concrete pavement design. it is our understanding that stamped concrete pavement is proposed for various areas of the project. We recommend a minimum concrete pavement section of 8 inches of Portland Cement Concrete (PCC) on compacted native soil or 6 inches of PCC on 4 inches of base material. We appreciate the opportunity to provide service to you on this. project, if you have any ' questions regarding this letter or the referenced report please contact the undersigned, Respectfully submitted, ' SLADUEN ENGINEERI ' Brett L. Anderson Principal Engineer. ' SER/lh Copies: 4 /Coachella Valley Engineers I I 1 1 ' 1 1 Sladden Engineering b d 01ZUIZ089'ON /l.b.8 '1S /8b 8 5002 bl 1nr(AHl) 183S30 W1Vd N30OV1S W08J GEOTECHNICAL INVESTIGATION TENTATIVE TRACT NO. 31249 AVENUE 58 WEST OF MADISON STREET LA QUINTA, CALIFORNIA - Prepared By- Sladden Engineering 39 -725 Garand Lane, Suite G Palm Desert, California 92211 (760) 772 -3893 t O Sladden Engineering 6782 Stanton Ave., Suite A, Buena Park, CA 90621 (714) 523 -0952 Fax (714) 523 -1369 39 -725 Garand Ln., Suite G, Palm Desert, CA 92211 (760) 772 -3893 Fax (760) 772 -3895 ' As requested, we have performed percolation /infiltration testing on the subject site in order to determine the infiltration potential of the surface soils. The percolation rates determined should be useful in assessing stormwater retention needs. It is our understanding that on -site stormwater 1 retention will be required. It is proposed to collect the stormwater runoff within several shallow retention basins. Infiltration testing was performed within shallow test holes excavated in the areas of two of the proposed retention basins. Percolation testing was performed on June 24, 2003. Testing involved filling the test holes with water and recording the drop in the water surface with time. Measurements were recorded in 10 and 15 minute increments. ' Tests results are summarized below: ' Rate Test Hole No. (inches /hour) A 10.8 B 6.6 It should be noted that the infiltration rates determined are ultimate rates based upon field test results. An appropriate safety factor should be applied to account for subsoil inconsistencies and potential silting of the percolating soils. The safety factor should be determined with consideration to other factors in the stormwater retention system design (particularly stormwater volume estimates) and the safety factors associated with those design components. September 11, 2003 Project No. 544 -3272 03 -09 -590 Madison 58 Partners, LLC 77 -899 Wolf Road, Suite 101 Palm Desert, California 92211 Project: Tentative Tract 31249 Avenue 58 west of Madison Street La Quinta, California ' Subject: Infiltration /Percolation Testing for Stormwater Retention As requested, we have performed percolation /infiltration testing on the subject site in order to determine the infiltration potential of the surface soils. The percolation rates determined should be useful in assessing stormwater retention needs. It is our understanding that on -site stormwater 1 retention will be required. It is proposed to collect the stormwater runoff within several shallow retention basins. Infiltration testing was performed within shallow test holes excavated in the areas of two of the proposed retention basins. Percolation testing was performed on June 24, 2003. Testing involved filling the test holes with water and recording the drop in the water surface with time. Measurements were recorded in 10 and 15 minute increments. ' Tests results are summarized below: ' Rate Test Hole No. (inches /hour) A 10.8 B 6.6 It should be noted that the infiltration rates determined are ultimate rates based upon field test results. An appropriate safety factor should be applied to account for subsoil inconsistencies and potential silting of the percolating soils. The safety factor should be determined with consideration to other factors in the stormwater retention system design (particularly stormwater volume estimates) and the safety factors associated with those design components. Septernber 11, 2003 -2- Project No. 544 -3272 03 -09 -590 We appreciate the opportunity to provide service to you on this project. If you have questions regarding this letter or the data included, please contact the undersigned. Respectfully submitted, SLADDEN ENGINEERING POFESS /o q z m Hogan R. Wright No. C 64276 Project Engineer * Exp. 6i3O/07 �'T9T C I V 11- P�\P Letter /pc FOF CA 1 CFO Copies: 4/ Madison 58 Partners, LLC CRAPtIlC SCALE N ..M 24 APORTION OFTHE NORTHEAST QUARTER OF THE NORTHWESTOUARTER INEI /. NW 1141 Of .n,� MAP S3 � SECtION 28. TOWNSHIP Q SOUTH• RANGE 7 EAST OF THE SAN BERNARDINO J.AER:CIAN. ti.(1. E ,_ COUNTY 01 RIVERSIDE. SI ATE Of CALIFORNIA '�' -CAFE: 7�'lEICPML:, C.OACSEU, l'A:LD ENGINEERS. NC. ,,W t...r. ..: .. •�t •I .IY N.,.LE ^. UII /,. w• ;' .Lalr: Ifay KMU :.l+,: I N°+,J �'f. .[:t.l •\� "".��: _.-� 1 vo ' L Sr 1 C\� 'I fuEar. •'�n� .•11,1 �� th�'2`, aI, t: `� ',�1i ca:�rr' eery 'A: ` /. -'�_,' s`J8^ +�,�.•- Ori7 > F —�\ '- • �iE V ' :` %'+o- �_�A7r„ '.r, +i. <;t,' A., � i. nl II A� i :J '.i7 � r!Y • ,,o' .IK •LLl :' v y �8•) T'I'. I: ' 1 _IE :.,, t_ jr „ E r : (.•- ilz ZIT a.o DW ■B �= :;. t' ,I t� ye ,., :'�., I _ tE o.Lee.r. %i:. �. i%p I ' j;!•;:.,:i 6.6 in. /hr.::i .. u ' �. �� , "i � � � '.�• ` :.'4' ,IT�B .// � 4 'y:.,.,._ L. 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'�4 J— ' —` __ __•t Yf,O- =.Y1, = _ ", II! .,`; Vm ' Percolation Test Location Map Proposed 33 -acre Residential Development Tentative Tract 31249 Avenue 58 west of Madison Street North Approximate Stormwater La QUinta, California Percolation Test Locations Sladden Engineering Project Number: 544 -3272 1 Date: 8 -20 -03 �e- Double Ring Stormwater Percolation Data Sheet Project: Tentative Tract 31249 / Madison St. / La Quinta, California Project No.: 544 -3272 Test Hole: A Date Excavated: 6 -24 -03 Percolation Tested by: Tracy Yeager Soil Classification: SM Date Tested: 6 -24 -03 Reading Time Time Inner Change Outer Change Outer Inner Outer No. of Interval Ring Inner Ring Outer Ring Ring Ring Readinq (min.) (in.) (in.) (in.) (in.) Conversion (in. /hr.) (in. /hr.) 1:27 18.4 28.1 1 10 3.1 3.8 3.2 18.6 19.4 1:37 15.3 24.3 + 1:37 15.3 24.3 2 10 2.9 3.6 3.1 17.4 18.4 1:47 12.4 20.7 1:47 12.4 20.7 3 10 2.8 3.5 3.0 16.8 17.9 1:57 9.6 17.2 1:57 9.6 17.2 4 10 2.7 3.4 2.9 16.2 17.3 2:07 6.9 13.8 2:07 6.9 13.8 5 10 2.5 3.1 2.6 15.0 15.8 2:17 4.4 10.7 2:17 4.4 10.7 6 10 2.3 2.7 2.3 13.8 13.8 2:27 2.1 8.0 2:27 18.2 8.0 7 10 2.1 2.4 2.0 12.6 12.2 2:37 16.1 5.6 2:37 16.1 5.6 8 10 2.0 2.2 1.9 12.0 11.2 2:47 14.1 3.4 2:47 14.1 3.4 9 10 1.8 2.2 1.9 .10.8 11.2 2:57 12.3 1.2 2:57 12.3 16.9 10 10 1.8 2.2 1.9 10.8 11.2 3:07 10.5 14.7 3:07 10.5 14.7 11 10 1.9 2.1 1.8 11.4 10.7 3:17 8.6 8.6 12.6 12.6 3:17 12 10 1.8 2.1 1.8 10.8 10.7 3:27 6.8 10.5 Double Ring Stormwater Percolation Data Sheet Project: Tentative Tract 31249 / Madison St. / La Quinta, California Project No.: 544 -3272 Test Hole: 6 Date Excavated: 6 -24 -03 Percolation Tested by: Tracy Yeager Soil Classification: SM Date Tested: 6 -24 -03 Reading Time Time Inner Change Outer Change Outer Inner Outer No. of Interval Ring Inner Ring Outer Ring Ring Ring Readina (min.) (in.) (in.) (in.) (in.) Conversion (in. /hr.) (in. /hr.) 9:34 18.2 28.3 1 15 4.0 5.0 4.3 16.0 17.0 9:49 14.2 23.3 9:49 14.2 23.3 2 15 2.9 3.7 3.1 11.6 12.6 10:04 11.3 19.6 10:04 11.3 19.6 3 15 2.4 3.0 2.6 9.6 10.2 10:19 8.9 16.6 10:19 8.9 16.6 4 15 2.1 2.7 2.3 8.4 9.2 10:34 6.8 13.9 10:34 6.8 13.9 5 15 1.8 2.4 2.0 7.2 8.2 10:49 5.0 11.5 10:49 5.0 11.5 6 15 1.8 2.2 1.9 7.2 7.5 11:04 3.2 9.3 11:04 18.0 9.3 7 15 1.8 2.1 1.8 7.2 7.1 11:19 16.2 7.2 11:19 16.2 7.2 8 15 1.8 2.2 1.9 7.2 7.5 11:34 14.4 5.0 11:34 14.4 5.0 9 15 1.7 2.1 1.8 6.8 7.1 11:49 12.7 2.9 11:49 12.7 11.6 10 15 1.6 2.1 1.8 6.4 7.1 12:04 11.1 9.5 12:04 11.1 9.5 11 15 1.7 2.2 1.9 6.8 7.5 12:19 9.4 7.3 12:19 9.4 7.3 12 15 1.8 2.2 1.9 7.2 7.5 12:34 7.6 5.1 0 � I 1 1 I 11 Slad en Engineering 6782 Stanton Ave., Suite A, Buena Park, CA 90621 (714) 523 -0952 Fax (714) 523 -1369 39 -725 Garand Ln., Suite G, Palm Desert, CA 92211 (760) 772 -3893 Fax (760) 772 -3895 August 20, 2003 Madison 58 Partners, LLC 77-899 Wolf Road, Suite 101 Palm Desert, California 92211 Project: Tentative Tract 31249 Avenue 58 West of Madison Street La Quinta, California Subject: GeotechnicalInvestigation Project No. 544-3272 03-08-544 Presented herewith is the report of our Geoteclinical Investigation conducted at the site of the proposed residential development located on the south side of Avenue 58 west of Madison Street in the City of La Quinta, California. The investigation was performed in order to provide recommendations for site preparation and to assist in foundation design for the proposed residential structures and the related site improvements. This report presents the results of our field investigation and laboratory testing along with conclusions and recommendations for foundation design and site preparation. This report completes our original scope of services as outlined in our proposal dated June 16, 2003. We appreciate the opportunity to provide service to you on this project. If you have any questions regarding this report, please contact the undersigned Respectfully submitted, SLADDEN ENGINEERING S: Copies= 6/Madison 58. Partners, LLC GEOTECBNICALlN\EQII8ATION TENTATIVE TRACT 3l848 AVENUE 5G WEST 0F MADISON STREET ~u LkODIN7A.[ALIFORNIA� August 22.20O8 TABLE OF CONTENTS INTRODUCTION ----------.----------------------------'l SCOPE OF WORK ----------_----.—._--------------------'l PROJECTDEGORIPTIO0� ............................................. . ...... ............... .......................................... I SUBSURFACE CONDITIONS .................................................................................................. 8 CONCLUSIONS AND RECOMMENDATIONS -----------------------' 2 FoundationDesign ............................................................................................................... 3 Settlements.......................................................................................................................... 3 LateralDesign ..................................................................................................................... 3 RetainingWalls ................................................................................................................... 4 ExpansiveSoils .................................................................................................................... 4 Concrete 8luba-ooz8rude ..................................................................................................... 4 SolubleSulfates ................................................................................................................... 4 Tentative PavumuozDoaign------'---- 4 andSubsidence .................................................................................................... 5 GeneralSite Grading ........................................................................................................... 5 l. Clearing and Grubbing -------------------------------5 2. Preparation uf Building and Foundation Areas ......................................... ............ 4 3. Preparation of Surfaces to Receive Compacted Fill ................................................ 5 4. Placement nf Compacted Fill .................................................................................... 5 5. Preparation uf Slab and Paving Areas ..................................................................... G 6. Teotingoozdlounoutiosz ------------------------------- G GENERAL.................................................................................................................................. G APPE0DIEK A' Site Plan and Boring Logs Field Exploration APPENDIX B' Laboratory Testing Laboratory Test Results APPENDIX C ' 1897 TJBC Seismic Design Criteria ' August 20,:2003 1 Project No. 544-3272 03-08-544 INTRODUCT16N ' This report presents the results of our Geotechnical Investigation performed in order to provide recommendations for site preparation and to assist in the design and construction of the foundations for the proposed residential structures. The project site is located on the south side of Avenue 58 west of Madison Street in the City of La Quinta, California. The preliminary plans indicate that the ' proposed project consists of an approximately 33 acre residential subdivision. The associated site improvements are expected to include paved roadways, concrete driveways, walkways and patios, swimming pools, landscape areas and various underground- utilities. — _.......... . iSCOPE OF WORK ' The purpose of our investigation was to determine certain engineering characteristics of the near surface soils on the site in order to develop recommendations for foundation design and site preparation. Our investigation included field exploration, laboratory testing, engineering analysis and the preparation of this report. Evaluation of environmental issues or hazardous wastes was not within the scope of services provided. Our investigation was performed in accordance with contemporary geotechnical engineering principles and practice. We make no other warranty, either express or implied. 1 PROJECT DESCRIPTION ' The project site is located on the south side of Avenue 58 west of Madison Street in the La Quinta area of Riverside County, California. The preliminary plans indicate that the project will consist of an approximately 33 acre residential subdivision. It is our understanding that the proposed residential structures will be of relatively lightweight wood-frame construction and will be supported ' by conventional shallow spread footings and concrete slabs on grade. The associated site improvements will include paved roadways, concrete walkways, patios and driveways, swimming pools, landscape areas and various underground utilities. lThe project site is mostly vacant and appears to have been previously used for agricultural production. The entire site is fallow but evidence of previous agricultural production and a nursery facility. Scattered concrete foundations and small structures exist along the north side of the site. There is existing water well located at the north central portion of the site. The adjacent property to the south, east and west of the site remains vacant. Avenue 58 forms the northern site boundary. There are existing overhead and underground utilities along Avenue 58 and possibly transecting the (� subject site. Based upon our previous experience with lightweight wood -frame structures, we expect that isolated I, column loads will be less than 30 kips and wall loading will be less than to 3.0 kips per linear foot. Grading is expected to include minor cuts and fills to match the nearby elevations and to construct slightly elevated building pads to accommodate site drainage. This does not include removal and recompaction of the foundation bearing soils within the building areas. If the anticipated foundation loading or site. grading varies substantially from that assumed, the recommendations included in this report should be reevaluated. August 20, 2003 -2- Project No.. 544-3272 03-08-544 SUBSURFACE CONDITIONS The near surface soils observed within our bo ngs consist primarily of fine-grained silty sands with scattered generally thin sandy silt, clayey silt, and silty clay layers. Silty fine-grained sands were ' the most'prominent soil type encountered but several prominent sandy silt and silty clay layers were also observed within several of our borings. In general, the site soils appeared somewhat loose near the surface but laboratory test results and sampler penetration resistance (as measured by field ' blowcounts) suggest that the site soils become somewhat firmer with depth. The majority of the site soils were found to be dry throughout the depth of our borings but some of the silt deeper layers were wet. Laboratory classification testing indicates that the near surface soils consist primarily of a somewhat inconsistent mixture of silty fine-grained sands. Expansion test results indicate that the majority of the near surface soils are non-expansive and fall within the "very low" expansion category in accordance with the Uniform Building Code classification system. Consolidation testing indicates that some of the near surface soils are potentially compressible and may be susceptible to _ detrimental hydroconsolidation.and/or compression related settlements. Groundwater was not encountered within our borings that extended to a maximum depth of approximately 51 feet below the existing ground surface. Groundwater should not be a factor in foundation design or construction. CONCLUSIONS AND RECOMMENDATIONS Based upon our field and laboratory investigation, it is our opinion that the proposed residential development is feasible from a soil mechanic's standpoint provided that the recommendations included in this report are considered in building foundation design and site preparation. Due to the somewhat loose and compressible conditions of the near surface soils, remedial grading including overexcavation and recompaction is recommended for the proposed building areas. We recommend that remedial grading within the proposed building areas include overexcavation and recompaction of the loose surface soils as well as the primary foundation bearing soils. Specific recommendations for site preparation are presented in the Site Grading section of this report. Groundwater was not encountered within our borings that extended to a depth of approximately 51 feet below the existing ground surface. Due to the depth to groundwater, specific liquefaction analyses were not performed. Based upon the depth to groundwater, the potential for liquefaction and the related surficial affects of liquefaction impacting the site are considered negligible. The site is located within an active seismic area of Southern California within approximately 13.5 kilometers of the San Andreas Fault system. Strong ground motion resulting from earthquake activity along the nearby San Andreas or San Jacinto fault systems is a—ely to impact the site during the anticipated lifetime of the structures. Structures should be designed by professionals familiar with the geologic and seismic setting of the site. As a minimum, structure design should conform to Uniform Building Code (UBC) requirements for Seismic Zone 4. Pertinent seismic design criteria as outlined in the 1997 UBC, is summarized in Appendix: C of this report. Caving did occur to varying degrees within each of our exploratory borings and the surface soils may be susceptible to caving within deeper. excavations. All excavations should be constructed in accordance with the normal CalOSHA excavation criteria. On the basis of our observations of the materials encountered, we anticipate that the subsoils will conform to those described by CalOSHA as Type C. Soil conditions should be verified in the field by a "Competent person" employed by the Contractor. i The majority of the surface soils encountered during our investigation were found to be non- expansive. Laboratory testing indicated an Expansion Index of 0 for the silty sands that dominatg the site, which corresponds with the very .low" expansion category in accordance with UBC Standard 15 -2. If imported soils are to be used during grading, they should have an Expansion ' Index of less than 20. The following recommendations present more detailed design criteria, which have been developed on ' the basis of our field and laboratory investigation. Foundation Design: The results of our investigation indicate that either conventional shallow continuous footings or isolated--pad- -footings —that are— supported— upon — properly ' compacted soils may be expected to provide satisfactory support for the proposed structures. Overexcavation and recompaction should be performed as. described in the Site Grading Section of this report. Footings should extend at least 12 inches beneath lowest adjacent grade. Isolated square or rectangular footings at least 2 feet square may be designed using an allowable bearing value of 1800 pounds per square foot. Continuous footings at least 12 inches wide may be designed ' using an allowable bearing pressure of 1500 pounds per square foot. Allowable increases of 200 psf for each additional 1 foot of width and 200 psf for each additional 6 inches of depth may be utilized if desired. The maximum allowable bearing pressure should be 2500 psf.. The allowable bearing pressures are for dead and frequently applied live loads and may be increased by 1/3 to resist wind, seismic or other transient loading. Care should be taken to see that bearing soils are not allowed to become saturated from the ponding of rainwater or irrigation. Drainage from the building areas should be rapid and complete. The recommendations made in the preceding paragraphs are based on the assumption that all footings will be supported upon properly compacted soil. All grading shall be performed under the testing and inspection of the Soils Engineer or his representative. Prior to the placement of concrete, we recommend that the footing excavations be inspected in order to verify that they extend into compacted soil and are free of loose and disturbed materials. Settlements: Settlements may result from the anticipated foundation loads. These estimated ultimate settlements are calculated to be a maximum of 1 inch when using the recommended bearing values. As a practical matter, differential settlements between footings can be assumed as one-half of the total settlement. Lateral Design: Resistance to lateral loads can be provided by a combination of friction acting at the base of the slabs or foundations and passive earth pressure along the sides of the foundations. A coefficient of friction of 0.40 between soil and concrete may be used with dead load forces only. A passive earth pressure of 275 pounds per square foot, per foot of depth, may be used for the sides of footings, which are poured against properly compacted native soils. Passive earth pressure should be ignored within the upper 1 foot except where confined (such as beneath a floor slab). When used in combination, either the passive resistance or the coefficient of friction should be reduced by one-third. . W August 20, 2003 -4- Project No.. 544-3272 03- 08-544. Retaining Walls: Retaining walls may be required to accomplish the proposed construction. Cantilever retaining walls may be designed using "active" pressures. Active pressures may be estimated using an equivalent fluid weight of 35 pcf for native backfill soils with level free-draining backfill conditions. For walls that are restrained, "at rest" pressures should be utilized in design. At rest pressures may be estimated using an equivalent fluid weight of 55 pcf for native backf1ll soils with level free-draining backfill conditions. Expansive Soils: Due to the prominence of non-expansive soils on the site, special expansive soil design criteria should not be necessary for - the - design -of- foundations_and- concrete..slabs- on-grade. Because the mixing and blending associated with the recommended remedial grading may change expansion potential, final design criteria should be established by the Structural Engineer based upon post grading expansion test results. Concrete Slabs-on-Grade: All surfaces to receive concrete slabs-on-grade should be underlain by.recompacted soils as described in the Site Grading Section of this report. Where slabs are to receive moisture sensitive floor coverings or where dampness of the floor slab is not desired, we recommend the use of an appropriate vapor barrier. Vapor barriers should be protected by sand in order to reduce the possibility of puncture and to aid in obtaining uniform concrete curing. Reinforcement of slabs-on-grade in order to resist expansive soil pressures may not be required. However, reinforcement will have a beneficial effect in containing cracking due to concrete shrinkage. Temperature and shrinkage related cracking should be anticipated in all concrete slabs-on- grade. Slab reinforcement and the spacing of control joints should be determined by the Structural Engineer. Soluble Sulfates: The soluble sulfate concentration of a bulk sample of the .near surface soils determined to be approximately 1560 parts per million (ppm) which is considered potentially corrosive with respect to concrete. The use of Type 5 cement or sulfate resistant concrete mix designs may be necessary. Soluble sulfate content of the surface soils should be reevaluated after rough grading. Tentative Pavement Design: All paving should be underlain by a minimum compacted fill thickness of 12 inches (excluding aggregate base). This may be performed as described in the Site Grading Section of this report. The following preliminary pavement sections are based upon a design R-Value of 50. Onsite Roadways (Traffic Index = 6.0) Use 3.0 inches of asphalt on 4.0 inches of Class 2 base material Aggregate base should conform to the requirements for Class 2 Aggregate base in Section 26 of CalTrans Standard Specifications, January 1992. Asphaltic concrete should conform to Section 39 of the CalTrans Standard Specifications. The recommended sections should be provided with a uniformly compacted subgrade and precise control of thickness and elevations during placement. August 20, 2003. Project No. 544-3272 03=08-544 ' Shrinkage and Subsidence: Volumetric shrinkage of the material that is excavated and replaced as controlled compacted fill should be anticipated. We estimate that this shrinkage should vary from 20 to 25 percent. Subsidence of the surfaces that are scarified and t compacted should be between 0.2 and 0.3 tenths of a foot. This will vary depending upon the type of equipment used, the moisture content of the soil at the time of grading and the actual degree of compaction attained. These values for shrinkage and subsidence are exclusive of losses which will occur due to the stripping of the organic material from the site, the removal of deleterious materials and the removal of debris, trees and other subsurface - obstructions. — - - General Site Grading: All grading should be performed in accordance with the grading ordinance of the City of La Quinta, California. The following recommendations have been developed on the basis of our field and laboratory testing: 1. Clearing and Grubbing: Proper clearing of any existing vegetation, root systems, debris, foundations, slabs, pavements and underground utilities will be very important. All surfaces to receive compacted 'fill should be cleared of roots, vegetation, debris, and other unsuitable materials that should be removed from the site. Soils that are disturbed due to site clearing should be replaced as controlled compacted fill under the direction of the Soils Engineer. 2. Preparation of Building and Foundation Areas: Building areas should be overexcavated to a depth of at least 3 feet below existing grade or 2 feet below the bottom of the footings, whichever is deeper. The exposed surface should be scarified, moisture conditioned and compacted so that a minimum of 90 percent relative compaction is attained: Once deleterious materials are removed, the native material may be placed as controlled compacted fill. Overexcavation should be observed by a representative of Sladden- Engineering and compaction should be verified by testing. 3. Preparation of Surfaces to Receive Compacted Fill: Other areas to receive compacted fill should be brought to near optimum moisture content and compacted to a minimum of 90 percent relative. compaction. 4. Placement of Compacted Fill: Fill materials consisting of on -site soils or approved imported granular soils, should be spread in thin lifts, and compacted at near optimum moisture content to a minimum of 90 percent relative compaction. Imported material shall have an. Expansion Index not exceeding 20. The contractor shall notify the Soils Engineer at least 48 hours in advance of importing soils in order to provide sufficient time for the proper evaluation of proposed import materials. The contractor shall be responsible for delivering material to the site, which complies with the project specifications. Approval by the Soils Engineer will be based upon material delivered to the site and not the preliminary evaluation of import sources. Our observations of the material encountered during our investigation indicate that compaction will be most readily obtained by means of heavy rubber - wheeled equipment and/or vibratory compactors. 1 1 August 20, 2003 -6- Project No. 544-3272 03-08-544 5. Preparation of Slab and Paving Areas: All surfaces to receive asphalt concrete paving or concrete slabs-on- grade, should be underlain by a minimum compacted fill thi&ness of 12 inches. This may be accomplished by a co" nation of scarification and recompaction of the surface soils and placement of the fill material as controlled compacted fill. Compaction of the slab and pavement areas should be to a minimum of 90 percent relative compaction. Testing and Inspection: During grading tests and observations should be performed by the Soils Engineer or his representative in order to verify that the grading is being performed in accordance with the project specifications: Field density testing shall be performed in accordance with - acceptable AS-T -M —test methods The.-Minimum acceptable degree of compaction should be 90 percent of the maximum dry density as obtained by the ASTM D1557-91 test method. Where testing indicates insufficient density, additional compactive effort shall be applied until retesting indicates satisfactory compaction. GENERAL The findings and recommendations presented in this report are based upon an interpolation of the soil conditions between the exploratory boring locations and extrapolation of these conditions throughout the proposed building area. Should conditions encountered during grading appear different than those indicated in this report, this office should be notified. This report is considered to be applicable for use by Madison 58 Partners, LLC for the specific site and project described herein. The use of this report by other parties or for other projects is not authorized. The recommendations of this report are contingent upon monitoring of the grading operation by a representative of Sladden Engineering. All recommendations are considered to be tentative pending our review of the grading operation and additional testing, if indicated. If others are employed to perform any soil testing, this office should be notified prior to such testing in order to coordinate any required site visits by our representative and to assure indemnification of Sladden Engineering. We recommend that a pre-job conference be held on the site prior to the initiation of site grading. The purpose of this meeting will be to assure a complete understanding of the recommendations presented in this report as they apply to the actual grading performed. APPENDI K.A Site Plan Boring Logs .,K For our field investigation, 8 exploratory borings were excavated on June 20, 2003, using a truck rdounted hollow stem auger rig (Mobile B61) in the approximate locations indicated on the site plan included in this appendix. Continuous logs of the materials encountered were prepared on the site by a representative of Sladden Engineering. Boring logs are included in this appendix. Representative undisturbed samples were obtained within our borings by driving a thin-walled steel penetration sampler (California split spoon sampler) or a Standard Penetration Test (SPT) sampler with a 140 pound hammer dropping approximately 30 inches (ASTM D1586). The number of blows required to drive the samplers 18 inches was recorded in 6 inch increments and blowcounts are indicated on the boring logs. The California samplers are 3.0 inches in diameter, carrying brass sample rings having inner diameters of 2.5 inches. The standard penetration samplers are 2.0 inches in diameter with an inner diameter of 1.5 inches. Undisturbed samples were removed from the sampler and placed in moisture sealed containers in order to preserve the natural soil moisture content. Bulk samples were obtained from the excavation spoils and samples were then transported to. our laboratory for further observations and testing. 1 1. 1 1 1 1 3 -D Tn110Quads Cupyri hI'D 1999 DeLarme YarmnuIh, ME 04096 Snurce Da 1a: US CS f --- jl000 rl Scale: 1 : 2i,0110 UeIai1: 13.0 DAIuin: N'C5S4 Vicinity Map Proposed 33 -acre Residential Development Tentative Tract 31249 Avenue 58 west of Madison Street North La QUinta, California Sladden Engineering Project Number: 544 -3272 1 Date: 8 -20 -03 i4ir:.:. :,. ��; � ' F ..' • i � _ it -_ -r:i J - ;;:: . (' '_ N7aLYJ \':. '_: -_= :�L -� 1•_ I', :_•'�_�. `.. � •' 'iii -.i:: a .._..... P. 4 •a ''�ti :- - :��:. c ''fir NR .•...u_ ^., I I� •L _ rte' Z. ..� ( - ^..! h• '.•� t= ' = AVENUE SP =.'T_ -•_ SITE 2 27 `,14 ' ` 'Cahui'� �n ' i .� %�4 ji;: <'„•T n �k „I ;ti Z °ry 2 �;_' ..`7F , I:I .�•`l' �`I :�''I% \:x':41 1 ;' 9'°c�, ;II- „..�,� d //' �� .._: .� .r i.. 1 I I I '•` :. �,p 1 it `. 1,_ �•= � Wit(= -�.,_ q:.�,; _ . �_:• ::. \.. ..., ' F I 4 _ ti -: ••_.-..� Jam.' (.”' � � . •,' '32 I 33 3 ... 1 ,;y�• j ='1 I �. � is �; - •..'',�� 3 -D Tn110Quads Cupyri hI'D 1999 DeLarme YarmnuIh, ME 04096 Snurce Da 1a: US CS f --- jl000 rl Scale: 1 : 2i,0110 UeIai1: 13.0 DAIuin: N'C5S4 Vicinity Map Proposed 33 -acre Residential Development Tentative Tract 31249 Avenue 58 west of Madison Street North La QUinta, California Sladden Engineering Project Number: 544 -3272 1 Date: 8 -20 -03 TENTATWE TR&CT'M CRANK. SCALE MO.. �ffM@),- A-PORTIONO F;HE NORTH W-1 QUARTER TER I -qE I . /I N%Y 1141 OF SECIPON 28.IOWNSHIP 6 SOUTH, RANGE 7 EAZr OF THE SAN BERNARDINO MERVAN. COU111YOF R•MIDE. SIMEOTCALWO RMA -A Q % . . . . . . . . . . �F AVENUE-f-7- 7— Fin, 7) J ;j. A -N IT t f . ........ . . . . . . " (D 7 T- tic, L n-�71 It T zy IN 0: -7 0.1 -j- J, 32 LE ..'69 I o ith J: J, VV Approximate Boring Locations 29. it i it Proposed 33 Acre Residential Development Tentative Tract 31249 /Avenue 58 west of Madison Street / La Quinta, California Date: 6 -20 -03 Borinv No. 1 Tob No.: 544 -3272 0 DESCRIPTION -�° A o REMARKS � c Li C Q� C% u q Ul r7� o o 0 0 V O _ Sand: Brown, SP /SM _ slightly silty, fine grained s - 8/8/12 - — '106 - -' ' -i - - -9 %passing - #200--- - -- 10 6/.10/14 98 2 - -- 9% passing #200 15 _ 8/10/10 - -- 2 - -- 9% passing #200 m i N i p i i w i W N N . . . i i i r i i N i i ° ° ° ° ° Depth wU (in feet) �* m Symbol Core C O p _ 0 0 0 W W 00 oo Blows/6 in. N N N po o� CD - cn < cn CD En ' 0 �. p VG � U) � ;ro C CID o o ° cv pq w a �d y v o . co . CD . co CL � n Soil Type b CD 4 0. o O 4. N G! a Unit Dry Wt. ce: o (Pct % Moisture ° rn % Relative CD ° c-D Compaction c� 0 z zzo c�nGO0 ° ° w 0 0 o a aj l➢ y G ° d w� [o as O as N • rwr U c (� w co - o 0 o o 0 p� ❑o" w � X. � O C' C coo a. m r as y p w o a CL CD V� IJ v, J is Proposed 33 Acre Residential Development Te ntafive Tract 31249 /Avenue 58 west of Madison Street / La Quints, California Date: 6 -20 -03 Bori�i� No. 3 .lob No.: 544 -327? b � O DESCRIPTION REMARKS d ❑ q :. � CO o U pa v� 0 Clayey Silt: Brown ML #200 s slightly silty, fine grained 10/12/16 —93— 7— Proposed 33 Acre Residential Development Te ntafive Tract 31249 /Avenue 58 west of Madison Street / La Quints, California Date: 6 -20 -03 Bori�i� No. 3 .lob No.: 544 -327? b � O DESCRIPTION REMARKS d ❑ q :. � CO o U pa v� 0 Clayey Silt: Brown ML s 10/12/16 —93— 7— - -- 86 %- passing- #300 - - - -- . 10 _ 18/24/28 Sand: Brown, SP /SM 110 1 - -- 8% passing s - 12/18/28 100 3 - -- 9% passing #200 zo :8/12/16 97 2 - -- 7% passing #200 - Total Depth = 21.5' - - Recovered Sample No Bedrock - No Groundwater 25 - 30 i I 35 40 45 50 Note: The stratification lines 55 represent the approximate boundaries between the soil types; the transitions may be gradual. . r r. T" N. . . . W i W' �' i i i N p i i i i- . i, i N . . . . o O (n O, cn O' N 0 N o Depth feet) d' (in (D Symbol Core Oa.;.: o`o oN 00 ` w LA Blows/6 in. - ® ca w �� '"� �, CO v� �cn .Y.... CD �fcrov'a o �� (D � �.'..:. CD p cn cn cn CL 11 �. tp < Ip c" s io °' O CD z z W En Soil Type �.. ; Unit Dry Wt. m (Pcf) p' CL �. 00 % Moisture ° d o V]'C; rt �: % Relative ►° Compactio>p z' co . rp .,�., zz -i �o�,z o00 0 CD G ti by C'y O N ° i 0 a F o 0 w �' F' _z T 7 p Q w II y co -, .. N o0 0�0 o�v o�o� O ~ �t LA - O o O 0 O 0 O 0 z. ' Ipe . . o o �"wa Ur, �t m o �+ " cD p a : � w `" w ^0 N =' N ia? : I ` Proposed 33 Acre:Residential Development:. - :....: Tentative*Tract.31249 / Avenue 58 west of Madison Street /'La Quinta, California Date: 6 -20 -03 Boring No. 5 Job No.: 544 -3272 u C DESCRIPTION ° q o r REMARKS .• a� rn y G. A p., rA ° U °1 C4 ° V) c c . , o (j ° Silty Sand: Brown, SM - very silty, fine grained 5 8/10/22 Silty Sand: Brown, SM- --- - -3-8.0 /Q-passing- #200 - -- -- -- — 99 ----2— - fine grained 10 10/16/24 Sand: Brown, slightly silty SP /SM 92 2 - -- 32% passing #200 - - fine grained with thin - interbedded silt layers 15 10/18/24 Sand: Brown, slightly silty, SP /SM 112 1 - -- I0% passing #200 - - fine grained, trace gravel - :8110116 Silty Sand: Brown, SM 20 fine grained with thin interbedded silt layers 101 2 -- 23% passing #200 - Total Depth = 21.5 - Recovered Sample No Bedrock No Groundwater 25 30 35 40 45 50 _ Note: The stratification lines 55 represent the approximate boundaries between the soil types; the transitions may be graduap Gradation ASTM CI 17 &: C136 Project Number: 544 -3272 Project Name: Tract 31249 Sample ID: Boring 7 @ 5' Sieve Sieve Percent Size, in Size, mm Passing 1 " 25.4 100 3/4" 19.1 100 1/2" 12.7 100 9.53 100 #4 4.75 100 #8 2.36 100 416 1.18 100 #30 0.60 100 #50 0.30 97 #100 0.15 65 #200 0.074 23 July 9, 2003 MM 11111111111110 m■■n�� ■■■ii��na mmN■■iinnn mn■nu�n■i■i� maim �un■■ni��■■■n��m� ■■■iimm■■ ��nin■ °11u�u ■iiin%i� ' ��nnumm 11mmi■ ' Expansion Index .ASTM D 4529/UBC 29 -2 Job Number: 544 -3272 ' Job Name: Tract 31249 Lab ID: ' Sample ID: Bulk 1 @ 0 -5' Soil Description: Silty Sand I� Wt of Soil + Ring: 525.0 Weight of Ring: 179.0 Wt of Wet Soil: 346.0 Percent Moisture: 15% Wet Density, pcf: 104.8 Dry Denstiy, pcf: 91.2 %Saturation: 47.7 Expansion Rack # Date /Time 7/10/03 1 7:30 A.M. Initial Reading 0.500 Final Reading 0.500 Expansion Index 0 (Final - Initial) x 1000 1 ' E[ Sladden Engineering Date: 7/9/03 Tech: Jake Revised 12/10/02 APPENDIX C 1997 UBC Seismic Design Criteria August 20, 2003 -12- Project No. 544-3272 03-08-544 ' 1997 UNIFORM BUILDING CODE INFORMATION The International Conference of Building Officials 1997 Uniform Building Code contains substantial revisions and additions to the earthquake engineering section summarized in ' Chapter 16. Concepts contained in the 1997 code that will be relevant to construction of the proposed structure are summarized below. � I r i 1 Ground shaking is expected to be the primary hazard most likely to affect the site, based upon proximity to significant faults capable of generating large earthquakes. Major fault zones considered to be most likely to create._ strong-ground shaking at the site are listed below. Fault Zone Approximate Distance From Site Fault Type (1997 UBC) San Andreas 13.5 km A San Jacinto 27.8 km A Based on our field. observations and understanding of local geologic conditions, the soil profile type judged applicable to this site is SD, generally described as stiff or dense soil. The site is located within UBC Seismic Zone 4. The following table presents additional coefficients and factors relevant to seismic mitigation for new construction upon adoption of the 1997 code. Sladden Engineering Near-Source Near-Source Seismic Seismic Seismic Acceleration Velocity Coefficient Coefficient Source Factor, Na Factor, N, Ca C„ San Andreas 1.0 1.05 0.44 Na 0.64 N. San Jacinto 1.0 1.0 0.44 Na 0.64 N„ Sladden Engineering * * E Q F A U L T * Version 3.00 * * * * * * * * * * * * * * * * * * * * * * * 4 DETERNINISTIC.ESTIMATION OF PEAK ACCELERATION . FROM. .-DI.GIS.IZED FAULTS _____._.. JOB NUMBER: 544 -3272 DATE: 07 -12 -2003 JOB NAME: Proposed Residential Development Tentative Tract 31249 La Quinta, California CALCULATIOP NAME: Test Rug: Analysis FAULT - DATA -FILE NAME: CDHG LTE.DAT SITE COORDINATES: SITE LATITUDE: 33.6263 SITE LONGITUDE: 116.2568 SEARCH RADIUS: 100 mi ATTENUATION RELATION: 5) Boore et al. (1997) Horiz. - SOIL (310) UNCERTAINTY (M= Median, S= Sigma): M Number of Sigmas: 0.0 DISTANCE MEASURE: cd_2drp SCOND: 0 Basement Depth: 5.00 km Campbell SSR: Campbell SHR: COMPUTE PEAK HORIZONTAL ACCELERATION FAULT -DATA FILE USED: CDMGFLTE.DAT MINIMUM DEPTH VALUE (km): 0.0 1 1 -:1. --------------- EQFAULT SUMMARY --------- - - - - -- ----------------------------- DETERMINISTIC- SITE - PARAMETERS Page i ------------------------------------------------------------------------------- I (ESTIMATED MAX. EARTHQUAKE EVENT I APPROXIMAT-E--1 ------------ -------- -------------- ABBREVIATED I DISTANCE I MAXIMUM I PEAK JEST. SITE FAULT NAME 1 mi (km) I EARTHQUAKE I SITE JINTENSITY I MAG.(Mw) I ACCEL. 9 JMOD.MERC. SAN ANDREAS - Coachella 1 8.4( 13.5) 1 7.1 1 0.283 J IY, SAN ANDREAS - Southern 1 8.4( 13.5) 1 7.4 1 0.332 J I! SAN JACINTO -ANZA 1 17.3( 27.8) 1 7.2 1 0.178 1 VIII SAN JACINTO- COYOTE CREED. I 18.5( 29.7) 1 6.8 1 0.137 1 VIII BURNT MTN. 1 23.1; 37.1) 1 6.4 I 0.094 1 171I EUREKA PEAK 1 24.01 38.6)1 6.4 1 0.091 1 VII SAN 'ANDREAS San Bernardino 1 24.2,. 38.9)1 7.3 J 0.146 1 VIII SAN JACINTO - BORREGO 1 29.7( 47.8) 1 6.6 1 0.086 ) VII PINTO MOUNTAIN I 35.7( 57.5)1 7.0 1 0.092 1 V =i EARTHQUAKE VALLEY 1 36.0( 57.9) 1 6.5 1 0.070 1 EMERSON So. - COPPER MTN. I 36.9( 59.4)1 6.9 1 0.085 1 VII BRAWLEY SEISMIC ZONE 1 37.1( 59.7)1 6.4 1 0.065 1 VT_ PISGAH- BULLION MTN. - MESQUITE LK 1 38.2( 61.4) 1 7.1 1 0.092 I 1:I LANDERS 1 38.2( 61.5) 1 7.3 1 0.103 1 V -TI SAN JACINTO -SAN JACINTO VALLE`! 1 38.8( 62.4) 1 6.9 1 0.082 1 VII ELSINORE- JULIAN 1 40. 0( 64.4)1 7.1 1 0.089 1 VII NORTH FRONTAL FAULT ZONE (East) 1 43.1( 69.3) 1 6.7 1 0.083 1 VII ELMORE RANCH 1 44.1( 70.9) 1 6.6 1 0.064 1 VI ELSINORE- COYOTE MOUNTAIN 1 46.1( 74.2)1 6.8 1 0.068 1 VI ELSINORE- TEMECULA 1 46.8( 75.3) 1 6.8 1 0.067 1 VI SUPERSTITION MTN. (San Jacinto) 1 47.8( 76.9)1 6.6 1 0.060 1 V"I SUPERSTITION HILLS (San Jacinto)( 48.7( 78.4)1 6.6 1 0.059 1 VI JOHNSON VALLEY (Northern) 1 49.0( 78.9) 1 6.7 1 0.062 1 VI CALICO - HIDALGO I 50.5( 81.4)1 7.1 1 0.074 I VII NORTH FRONTAL FAULT ZONE (West) 1 54.7( 88.0) 1 7.0 1 0.081 1 VII LENWOOD - LOCKHART -OLD WOMAN SPRGS1 54.7( 88.1)1 7.3 1 0.078 1 VII HELENDALE - S. LOCKHARDT 1 62.4( 100.4)1 7.1 1 0.063 1 VI SAN JACINTO -SAN BERNARDINO I 62.5( 100.6) 1 6.7 1 0.051 1 VI ELSINORE -GLEN IVY I 62.8( 101.0)1 6.6 1 0.054 1 VI IMPERIAL I 63.2( 101.7) 1 7.0 1 0..059 1 VI LAGUNA SALADA• 1 65.9( 106.1) 1 7.0 1 0.057 1 VI CLEGHORN i 70.9( 114.1)1 6.5 1 0.042 1 VI ROSE CANYON 1 74.4( 119.8)1 6.9 1 0.050 1 VI NEWPORT- INGLEWOOD (Offshore) I 74.9( 120.5)1 6.9 1 0.049 1 VI CHINO- CENTRAL AVE. (Elsinore) 1 76.7( 123.5)1 6.7 1 0.053 1 VI CUCAMONGA 1 77.9( 125.4) 1 7.0 1 0.061 1 VI WHITTIER I 81.0( 130.3)1 6.8 1 0.044 1 VI SAN ANDREAS - Mojave 1 87.2( 140.3) 1 7.1 1 0.049 1 VI SAN ANDREAS - 1657 Rupture 1 87.2( 140.3)1 7.8 1 0.070 1 VI SAN JOSE 1 89.1( 143.4)1 6.5 1 0.042 I VI 1 1 --- -------------------------- DETERMINISTIC SITE PARAll-JETERS -- ---- - - - - -- A. Page 2 ---------------------------------- IESTIMATED MAX. EART;iQJAKE EVENT I APPROXIMATE ( ------ - - - - -- ------------------- ABBREVIATED I DISTANCE I MAXI[lUM I PEAK IEST. SITE FAULT NAME I mi (km) IEARTHQUAKEI SITE (INTENSITY 1 I MAG.(Mw) I ACCEL. g IMOD.MERC. CORONADO BANK I 89.2( 143.5) 1 7.4 I 0.056 1 VI SIERRA MADRE 1 92.0( 148.0) 1 7.0 1 0.054 1 VI ELYSIAN PARK THRUST I 93.5( 150.5)1 6.7 1 0.045 I VI GRAVEL HILLS - HARPER. LAKE I 94.1( 151.5)1 6.9 1 0.041 1 V NEWPORT- INGLEWOOD (L.A.Basin) 1 95.9( 154.4) 1 6.9 1 0.041 1 V COMPTON THRUST 1 99.5( 160.1) 1 6.8 I 0.046 1 VI VERDES PALOS 1 99.7 160.4) 1 7.1 I 0.044 1 VI + * * * * * * * *k* * * * * * + + +.,. * *. ++*******r+= +,:r +* **** + * + + + + +_r< + + + + + + + +.._ > +�: + -END OF SEARCH- 47 FAULTS FOUND WITHIN THE SPECIFIED SEARCH RADIUS. THE SAN AN DREAS - Coachella FAULT IS CLOSEST TO THE SITE. IT IS ABOUT 8.4 MILES (13.5 km) AWAY. LARGEST MAXIMUM- EAR.THQUAKE SITE ACCELERATION: 0.3319 g 1100 1000 •m I 700 600 500 400 owe Will 100 9 -100 -400 -300 -200 -100 CALIFORNIA FAULT MAP Tentative Tract 31249 / La Quinta, CA 0 100 200 3uu 400 5uu bu0 01 0 c� L a� U U i Em STRIKE -SLIP FAULT 5) Boore et al. (1997) Horiz. -SOIL (3 10) M =5 M =6 M =7 1 .1 .01 001 M =8 1 10 100 Distance [adist] (km) 11 r- 3 DIP -SLIP .FAULTS 5) Boore et al. (1997) Horiz. - SOIL (3 10) M =5 M =6 M =7 1 .1 .01 .001 T"Wee 1 10 100 Distance [adist] (km) .1 0 c� ^L, ^W, W U U 3 Rr TNn- THRUST FAULTS 5) Boore et al. (1997) Horiz. - SOIL (3 10) M =.6 M =7 M =8 1 .1 .01 .001 1 10 100 Distance [adist] (km) I I � MAXIMUM EARTHQUAKES ' Tentative Tract 31 249 ! La Quinea, C2 A 1 0 c� ^L, ^W, W U U N .01 � ooi 1 1 A 10 100 Distance (mi) :4'. EARTHQUAKE MAGNITUDES & DISTANCES Tentative Tract 31249 / La Quinta, CA 7.75 7.50 7.25 aD 7.00 c� 6.75 6.50 1 10 100 Distance (mi) N. . . . k i i i i i : : w i , i i w i i i i N i i i i N i i i , W I I I t 0 Ddinu w 0 cn 0 m 0 u, 0 N 0 (in feet) SymbolCore ° Blows / ' .•_. phi 7 i� 0^ vi .,� cn �] > ® rte. 0_ a- `t y n. �p 0`` () ; .. CI) 0- 0- = =1 Cn w ° o pj CA a r+ co CL CV co b7 CA 00 UG 71 - 0 0 w En CL CD i7 w N O (1) CD �� z fCD �a cn Soil Type 7 m F4 (n . (D ort. O Unit Dry Wt. :. II (Pct) w.. p cn ::--. N w N % Moisture % Relative . I COIn PaCfIOR �. ►,�"� \ CD L-' C xo Z a 0 0 CD 0 0 0 a v, d n. d v b o Ln b G nN co Q. T. T w II Ej. w h N �' tn �' .�.� V :3 y w w N N o0 ov N oa N �? 7 0 n b ~ LA wDb� O O O o O o O O Ya a w y�yy O 7 ti W C/) ZI w o co 7• ,A �J cD �1 "'. hJ 1 A �J fi J 'I Proposed 33 Acre Residential Development Tentative Tract 31249 / Avenue 58 west of Madison Street / La Quinta, California Date: 6 -20 -03 Borino �'o. 7 i lob No.: 544 -327 � O y — DESCRIPTION = REMARKS o � a rn U Ca W _� o U 0 Sandy Silt: Brown, ML - slightly clayey Silty Sand: Brown, SM.. 5 9/18/24 - fine grained 10 10/16/22 Sand: Brown, SP /SM 98 1 - -- 14% passing #200 - _ slightly silty, fine grained is 12/16/26 102 2 -- 17% passing #200 20 :10/18/24 " 106 1 - -- 141,6 passing #200 Total Depth = 21.x' - ® Recovered Sample No Bedrock No Groundwater 25 30 35 40 45 50 Note: The stratitication lines - represent the approximate 55 boundaries between the soil ty pes; the transitions may be gradual. 1 II I 'I i Proposed 33 Acre Residential Development Tentative Tract 31249 / Avenue 58 west of Madison Street / La Quinta, California Date: 6 -20 -03 B .lob No.: X44 -3277) v — �B >_ ^ Cj DESCRIPTION :� a a REMARKS , , u > F" C CU o. u o p W o o -. -�U Q U q 0 �- 0 Clayey Silt: Brown with thin ML - interbedded silty sand layers s 12/18/_. , , —90 -- - 3— _6- 11o_passing. 8200 '0 28/50 -6" Sand: Brown, SP /S1\9 105 0 - -- 7% passing #200 - slightly silty, fine grained �5 10114/16 I 94 2 - -- 13' /o passing "200 20 8/12/16 Clayey Silt: Brown ML 100 22 -- 86% passing 4200 Total Depth = 21.5' _ ® Recovered Sample No Bedrock No Groundwater 25 30 35 40 45 50 - Note: The stratification lines - represent the approximate 55 boundaries between the soil types' the transitions may be gradual. APPENDIX -B - -- Laboratory Testing Laboratory Test Results APPENDIX B LABOPATORY TESTING Representative bulk and relatively undisturbed soil samples were obtained in the field and returned to our labofatory for additional observations and testing. Laboratory testing was generally performed in two phases. The first phase consisted of testing in order to determine the compaction of ' the existing natural soil and the general engineering classifications of the soils underlying the site. This testing was performed in order to estimate the engineering characteristics of the soil and to serve as a basis for selecting samples for the second phase of testing. The second phase consisted of soil mechanics testing. This testing including consolidation, shear strength and expansion testing t was performed in order to provide a means of developing specific design recommendations based on the mechanical properties of the soil. ' CLASSIFICATION AND COMPACTION TESTING Unit Weight and Moisture Content Determinations: Each undisturbed sample was weighed and ' measured in order to determine its unit weight. A small portion of each sample was then subjected to testing in order to determine its moisture content: This was used in order to determine the dry density of the soil in its natural condition. The results of this testing are shown on the Boring Logs. ' Maximum Density-Optimum Moisture Determinations: Representative soil types were selected for maximum density determinations. This testing was performed in accordance with the ASTM Standard D1557-91, Test Method A. The results of this testing are presented graphically in this ' appendix. The maximum densities are compared to the field densities of the soil in order to determine the existing relative compaction to the soil. This is shown on the Boring Logs, and is useful in estimating the strength and compressibility of the soil. tClassification Testing: Soil samples were selected for classification testing. This testing consists of mechanical grain size analyses and Atterberg Limits determinations. These provide information for developing classifications for the soil in accordance with the Unified Classification System. This t classification system categorizes the soil into groups having similar engineering characteristics. The results of this testing are very useful in detecting variations in the soils and in selecting samples for further testing. SOIL MECHANIC'S TESTING ' Direct Shear Testing: One bulk sample was selected for Direct Shear Testing. This testing measures the shear strength of the soil under various normal pressures and is used in developing parameters for foundation design and lateral design. Testing was performed using recompacted test specimens, which were saturated prior to testing. Testing was performed using a strain controlled ' test apparatus with normal pressures ranging from 800 to 2300 pounds per square foot. Expansion Testing: One bulk sample was selected for Expansion testing. Expansion testing was performed in accordance with the UBC Standard 18-2. This testing consists of remolding 4-inch diameter by 1-inch thick test specimens to a moisture content and dry density corresponding to approximately 50 percent saturation. The samples are subjected to a surcharge of 144 pounds per square foot and allowed to reach equilibrium. At that point the specimens are inundated with distilled water. The linear expansion is then measured until complete. ' Consolidation Testing: Four relatively undisturbed samples were selected for consolidation testing. For this testing one-inch thick test specimens are subjected to vertical loads varying from 575 psf to 11520 psf applied progressively. The consolidation at each load increment was recorded prior to placement of each subsequent load. The specimens were saturated at the 575 psf or 720 psf load ' increment. ' Maximum Density /Optimum Moisture ASTM D698 /D 1557 ' Project Number: 544 -3272 ' Project Name: Tract 31249 ' Lab ID Number: Sample Location: Bulk 1 @ 0 -5' Description: Silty Sand Maximum Density: 108 pcf Optimum Moisture 15.5% '1 .N Sieve Size � C 3/4" ' 3/8'• 1 WENE #4 A July 9, 2003 ASTM D -157 A Rammer Type: Machine % Retained law) ' 140 135 130 125 i W .N � C ' A 120 WENE A 11? 110 105 100 July 9, 2003 ASTM D -157 A Rammer Type: Machine % Retained lea � ��r•�a■�� ° ®® 0 5 10 15 20 - Moisture Content, 1' 25 i W L3 EW i WENE !!!•!!�!•!•!•Ol•��\ ► ►fit• t t•!•!•t•��vl• 1.1.1•�!•1•t•�!•��!• W WIN'= t t•�!•!•t•!•�� EMU ===MEN m mmmmm 0 5 10 15 20 - Moisture Content, 1' 25 Maximum Density /Optimum Moisture ASTM D698/D 1357 July 9, 2003 -._Proiect Number: 544-3272 ASTMD-1557 A Project Name: Tract 31249 Number: Kammer Type: Machine Lab ID Sample Location: Bulk 3 @ 0-5' (Max Only) Description: Sandy Silt Maximum Density: 117.5 pcf ... .... Optimum Moisture 12.5% Sieve Size % Retained 3/4f' 33/8" #4 145 140 135 130 125 M 120 lic 10' 100 0 5 10 15 Moisture Content, % .4U 5 mom 100 0 5 10 15 Moisture Content, % .4U 5 ' Direct Shear ASTM D 3080 -90 (modified for unconsolidated, undrained conditions) July 9, 2003 Initial Dry Density: 104.; pcf Initial Mosture Content: 15.5 % Peak Friction Angle (CAS): 31 ° Cohesion (c): 40 psf Test Results 1 544 3 Job Number -3272 ' Job Name Tract 31249 21.2 Lab ID No. 21.2 Saturation, % tSample ID Bulk 1 @ 0 -5' 92.7 Classification Silty Sand ' 0.301 Sample Type Remolded @ 90% of Maximum Density July 9, 2003 Initial Dry Density: 104.; pcf Initial Mosture Content: 15.5 % Peak Friction Angle (CAS): 31 ° Cohesion (c): 40 psf Test Results 1 2 3 4 Average Moisture Content, % 21.2 2102 21.2 21.2 21.2 Saturation, % 92.7 92.7 92.7 92.7 92.7 Normal Stress, kips 0.151 0.301 0.603 1.206 Peak Stress, kips 0.126 1 0.234 0.369 0.765 • Peak Stress Linear (Peak Stress) 1.2 1.0 I I I o.s N u ..' 0.6 En v I I + 0.4 I � 1 0.2 0.0 0:0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 Normal Stress Job Number: 544-3272 Job Name: Tract 3 ) 1249 Sample ID: Boring I @ 5' Soil Description: Silty Sand One DimensiOP21 I Consolidation ASTM D2435 &- D5333 July 9, 2003 Initial Dry Density, pcf: 109.2 Initial Moisture, W I Initial Void Ratio: 0.526 Specific Gravity: 2.67 % Change in Height vs Normal Presssure Diagram o Before Saturation c After Saturation 9 Rebound —m —Hydro Consolidation I 0 t -1 -2 -3 -4 5 -6 -7 -9 One DimensiOP21 I Consolidation ASTM D2435 &- D5333 July 9, 2003 Initial Dry Density, pcf: 109.2 Initial Moisture, W I Initial Void Ratio: 0.526 Specific Gravity: 2.67 % Change in Height vs Normal Presssure Diagram o Before Saturation c After Saturation 9 Rebound —m —Hydro Consolidation 3.0 -,.0 5.0 6.0 7.0 0.0 1.0 2.0 W F 3.0 -,.0 5.0 6.0 7.0 0.0 1.0 2.0 3.0 -,.0 5.0 6.0 7.0 Job Number: 544-3272 Job Name: Tract ' ) 1249 Sample ID: Boring 3 @ 5' Soil Description: Sandy Silt 1 One Dimensions[ Consolidation AST1\4 D24135 &-- D5333 Initial Dry Density, pcf-. Initial Moisture, %: Initial Vold Ratio: Specific Gravity: % Chancre in Height N's Normal Presssure Diagram 0 el 0 Before Saturation c After Saturation E) Rebound —w–Hydro Consolidation July 9, 200' ) 85.8 7 0.943 2.67 I 0 1 0.0 1.0 -3 -4 -5 -7 -8 -9 One Dimensions[ Consolidation AST1\4 D24135 &-- D5333 Initial Dry Density, pcf-. Initial Moisture, %: Initial Vold Ratio: Specific Gravity: % Chancre in Height N's Normal Presssure Diagram 0 el 0 Before Saturation c After Saturation E) Rebound —w–Hydro Consolidation July 9, 200' ) 85.8 7 0.943 2.67 3.0 4.0 5.0 r-. i - .3 -j - -- i^_,.:_ --- - - 6.0 7.0 0.0 1.0 3.0 4.0 5.0 r-. i - .3 -j - -- i^_,.:_ --- - - 6.0 7.0 1 A Job Number: 544 -3272 Job Name: Tract 31249 1249 Sample ID: Boring 5 @ 10' Soil Description: Silty Sand 1 One Dimensional Consolidation ASTM D2435 & D5333 July 9, 2003 Initial Dry Density, pcf: 89.2 Initial Moisture, %: ? Initial Void Ratio: 0.870 Specific Gravity: 2.67 --ley drocol apse: 1.00/o--@F0-.575,ksf % Chancre in Height vs Normal Presssure Diagram e Before Saturation L After Saturation 9 Rebound = Hydro Consolidation 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 I ... :__I I 1 -1- L 1 0 I -I 0.5 -2 -3 -4 -5 1 -6 -7 - 8 -9 I 10 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 I ... :__I I 1 -1- 0.0 0.5 1.0 1 ■ ■ 11 NEW MWIN 101� =KM NIM EWE MEE MM 0 ===1wM1WM0M �M=Wm ■w WE MINNIMMMMOMM MONEME -MWEEIE�— �MWNOE OEM MMI�WWE WE MME ■ �EEOE OEM 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 I ... :__I I 1 -1- 0.0 0.5 1.0 1 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 I ... :__I I 1 -1- Cne Dimensional Consolidation ASTM D2:35 & D5333 r Jut), 9, 2003 Initial Dry Density, pcf: 93.4 Initial Moisture, %: 1 Initial Void Ratio: 0.785 Specific Gravity: 2.67 % Change in Height vs Normal Presssure Diagram 0 Before Saturation A After Saturation –) Rebound —Q-- Hydro Consolidation 1 ' 0 t 0.0 ' Job Number: 544 -3272 Name: Tract 31249 -4 'Job Sample ID: Boring 7 @ 10' Soil Description: Silty Sand w -7 s - -8 Cne Dimensional Consolidation ASTM D2:35 & D5333 r Jut), 9, 2003 Initial Dry Density, pcf: 93.4 Initial Moisture, %: 1 Initial Void Ratio: 0.785 Specific Gravity: 2.67 % Change in Height vs Normal Presssure Diagram 0 Before Saturation A After Saturation –) Rebound —Q-- Hydro Consolidation ?.0 2.5 3.0 3.5 4.0 4.5 5.0 ... - -, 1 ' 0 0.0 0.5 1.0 -3 -4 ' -5 -6 w -7 s - -8 r -9 10 ?.0 2.5 3.0 3.5 4.0 4.5 5.0 ... - -, 0.0 0.5 1.0 1.5 w s - �� mom �WWmWW�W��e mom 2 son!��W�W ■W��W�WW� �WW��■W W �� WoW.W ?.0 2.5 3.0 3.5 4.0 4.5 5.0 ... - -, 0.0 0.5 1.0 1.5 ?.0 2.5 3.0 3.5 4.0 4.5 5.0 ... - -, Gradation ASTM C1 17 & C136 Project Number: 544-3272 July 9, 2003 Project Name: Tract 31249 Sam'ple ID: Bulk I @ 0-5' Sieve Sieve Percent Size, in Size,- = Passing A 25.4 100 31/411 19.1 100 1/2" 12.7 100 .3/811 9.53 100 94 4.75 100 48 2.36 100 #16 1.18 100 430 0.60 100 450 0.30 88 9100 0.15 35 ,4200 0.074 11 I I - I- — — - --- M °°�n1°�lilnn�l uin°�� _- . , 101 �IW■O�Im■ � InO�m Ilnnv�ln� In° m In■■n�la� 1 ■ = 1100 111 1 NS off Project Number: Project Name: Sample ID Gradation ASTM Cl 17 & C136 544 -3272 Tract 31249 Boring 1 @ 5' .a. July 9, 2003 Sieve Sieve Percent Size, in Size,-= Passing _. _..1. "._......_..... 25.4 100 3/4" 19.1 100 1/2" 12.7 100 3/8" 9.53 100 #4 4.75 100 #8 2.36 100 916 1.18 100 #30 0.60 100 950 0.30 86 #100 0.15 34 #200 0.074 9 " 81 Its 1■ ' un0■■■Illn■■■11111�► 111 ■■■■lnfl■■ m■o■iill�■■■■iinn� ■uln■■■■uln■■■ Illin■011110■■■■Ilin■�► 11 ■ ■■■ulln■0 .' Ilin■■■■Illlm ■■Illn■1 111 ■ ■ ®u10■ IIIlm01111� ■■■In1■��111 ■■■■11® innm■iilm■■■iin�■■■�mn■■■■nln■ iill� ®■iilln■■■umnn�nn■■o®■■■■ . �' iiumonlnn ■�11�■■■�iiun■v ®■ ia■■■ulu■■■iil °nip � ■v � 1� ' �� II� ■��110 � C1I.. .a .�.-. _. L1r IYt •1GPYl Y1R ■ " �■ 011® ®� . , MEMMIn1UMEMI1, n11® 11111 ®� Il MMM IM1 110 I miln® �� , Inn■��111m��uR, ��In nln��0 1 ®nH®1m��un►�u� n�� ' ��nnnuv�lll� ilmm� 1n1��1111n��i11111ty� � ' ��inmu III n mn� ' 1 Q'i -4rlan Fnvinr.Prina Gradation ' 17 &- C136 ASTM C1 ' Project Number: 544- 3272 "° July 9; 200' Name: Tract 31249 ' Sample ID: Boring 3 @ 10' ' Sieve Sieve Percent Size, in Size; mm Passing 1" 25.4 100 ' 3/4" 19.1 100 1/2" 12.7 100 3/8" 9.53 100 ' 44 4.75 100 #8 2.36 100 #16 1.18 100 #30 0.60 83 #50 0.30 39 ' #100 0.15 16 9200 0.074 8 r . ■ " �■ 011® ®� . , MEMMIn1UMEMI1, n11® 11111 ®� Il MMM IM1 110 I miln® �� , Inn■��111m��uR, ��In nln��0 1 ®nH®1m��un►�u� n�� ' ��nnnuv�lll� ilmm� 1n1��1111n��i11111ty� � ' ��inmu III n mn� ' 1 Q'i -4rlan Fnvinr.Prina REF: Retention D - 3 Hr /100Yr - Trapezoid Retention 4:1 Sideslope JOB # 02226 T.M. 31249, Ave 58 / Coral Mt Ct, West of Madison - La Quinta SHEET 1 OF 2 DATE: 7/7/06 BY: DLC RETENTION BASIN STORAGE AND DEPTH CALCULATIONS PERIOD WATER DEPTH WATER SURFACE D= 4' -5' D= 3'-4' D= 2' -3' D= V -2' D= 0' -1' DEPTH AREA ADJ.AREA ELEV. (15 Min) (FT) (FT) (FT) 011 1 u! 11 1 (FT) (FT) (SF) (SF) (FT) t4 101 1 11 1 n" 1 0.00 0.00 111 1 0.00 0.06 0.06 2344.74 2344.74 466.06 •� 1 1 1 - 1 1 2 0.00 0.00 0.00 0.00 0.11 0.11 • nS ��`�.yf }"�� 't' ��j�� '�'.h'� :.�,'�.4• :�� ytf�1.'.,��' !i �'j �' °�4'�9• _�.5'3V�, ��A1'ii `.�"} jay ,�;$� i�'�f.. °7;±y'rJrl` '° • �,;.@j',/�� iY - � �� th'�Q']Ii� PERIOD WATER DEPTH WATER SURFACE D= 4' -5' D= 3'-4' D= 2' -3' D= V -2' D= 0' -1' DEPTH AREA ADJ.AREA ELEV. (15 Min) (FT) (FT) (FT) (FT) (FT) (FT) (SF) (SF) (FT) 1 0.00 0.00 0.00 0.00 0.06 0.06 2344.74 2344.74 466.06 INC 2 0.00 0.00 0.00 0.00 0.11 0.11 2423.97 2423.97 466.11 INC 3 0.00 0.00 0.00 0.00 0.17 0.17 2510.25 2510.25 466.17 INC 4 0.00 0.00 0.00 0.00 0.22 0.22 2588.80 2588.80 466.22 INC 5 0.00 0.00 0.00 0.00 0.30 0.30 2716.36 2716.36 466.30 INC 6 0.00 0.00 0.00 0.00 0.39 0.39 2862.72 2862.72 466.39 INC 7 0.00 0.00 0.00 0.00 0.50 0.50 3040.59 3040.59 466.50 INC 8 0.00 0.00 0.00 0.00 0.62 0.62 3233.92 3233.92 466.62 INC 9 0.00 0.00 0.00 0.00 0.81 0.81 3534.59 3534.59 466.81 INC 10 0.00 0.00 0.00 0.08 0.00 1.08 3975.33 3975.33 467.08 INC 11 0.00 0.00 0.00 0.25 0.00 1.25 4288.04 4288.04 467.25 INC 12 0.00 0.00 0.00 1 0.26 0.00 1.26 4302.56 4302.56 467.26 PEAK p.A3.19 STORAGE HYDROGRAPH FOR 100 YEAR / 3 HR STORM RETENTION BASIN. SHEET 2 OF 2 PREPARED BY COACHELLA VALLEY ENGINEERS SUBJECT I Retention D - 3 Hr /100Yr -Trapezoid Retention 4:1 Sideslope JOB # 02226 T.M. 31249, Ave 58 / Coral Mt Ct, West of Madison - La Quinta DATE: 7/7/06 BY: DLC TRIB AREA= 1.394 ACRES PERC.RATE 2.00 IN /HR (0..5 IN/15 Min) SOIL GROUP "B ", AMCII, R.I.= 56, R.C. =50 %, STORM VOLUME 2.10 IN /3HR - . PERIOD PRECIP INTENSITY IMPERV FLOW INFLOW OUTFLOW RETENTION 1 100 C Q VOL /15 Min CUML VOL OTHER PERC /15Min OTHER REQD CUML VOL (15min) % (IN /15min) (CFS) (CF) (CF) (CF) (CF) (CF) (CF) RC =50% 1 3.7 0.078 0.485 0.210 189.2 189.2 0.0 97.7 0.0 91.5 2 4.8 0.101 0.493 0.277 249.5 341.0 0.0 101.0 0.0 240.0 3 5.1 0.107 0.495 0.296 266.3 506.3 0.0 104.6 0.0 401.7 4 4.9 0.103 0.494 0.283 255.1 656.8 0.0 107.9 0.0 549.0 5 6.6 0.139 0.507 0.391 352.3 901.3 0.0 113.2 0.0 788.1 6 7.3 0.153 0.512 0.437 393.6 1181.7 0.0 119.3 0.0 1062.4 7 8.4 0.176 0.520 0.511 460.1 1522.5 0.0 126.7 0.0 1395.9 8 9.0 0.189 0.524 0.552 497.1 1893.0 0.0 134.7 0.0 1758.3 9 12.3 0.258 0.548 0.790 710.9 2469.1 0.0 147.3 0.0 2321.8 10 17.6 0.370 0.587 1.210 1089.4 1 3411.3 0.0 165.6 0.0 3245.6 11 16.1 0.338 0.576 1.087 977.9 4223.5 0.0 178.7 0.0 4044.9 12 4.2 0.088 0.489 0.240 216.4 4261.2 0.0 179.3 0.0 4082.0 p.A3.20 76;; Ili m m m m m m m m m m m m m m m m m SUBJECT I Retention D - 6 Hr /100Yr - Trapezoid Retention 4:1 Sideslope JO6 # 02226 T.M. 31249, Ave 58 / Coral Mt Ct, West of Madison - La Quinta SHEET 1 OF 2 DATE: 7/7/06 BY: DLC RETENTION BASIN STORAGE AND DEPTH CALCULATIONS ,^•1q 'ri: � BUY i:is �•4 rvv..� D= 4' -5' D= 3'-4' Fyr . �V�,ti��'mj� D= 0' -1' EPTH AREA j,�c � y Cp`i�^�.Q�!��y[yt�.,''��i"� (FT) (FT) (FT) (FT) (FT) ED (FT) (SF) (SF) (FT) YY 1 0.000 0.000 0.000 0.000 0.027 0.03 2289.21 2289.21 466.03 INC 2 0.000 0.000 0.000 0.000 0.031 0.03 2294.49 2294.49 466.03 tY:2 =J 3 0.000 1 0.000 0.000 0.000 0.034 0.03 2299.80 2299.80 466.03 INC 4 0.000 0.000 0.000 0.000 0.038 111 1 2306.27 2306.27 466.04 INC 5 0.000 0.000 0.000 0.000 0.045 0.05 2317.98 2317.98 466.05 INC 6 0.000 11 1 0.000 0.000 0.053 0.05 2329.43 2329.43 466.05 INC 7 0.000 0.000 0.000 0.000 0.060 0.06 2340.63 2340.63 7, roB�ti.' INC 8 0.000 0.000 0.000 0.000 0.068 0.07 2354.30 2354.30 466.07 INC 9 0.000 0.000 0.000 0.000 0.078 0.08 2370.37 2370.37 466.08 INC 10 0.000 0.000 0.000 0.000 0.090 0.09 2388.83 2388.83 466.09 INC 11 0.000 0.000 0.000 0.000 0.103 0.10 2409.62 fl. 466.10 INC wInEmm. 0.000 0.000 0.000 0.000 0.119 0.12 2435.45 PERIOD WATER DEPTH WATER SURFACE D= 4' -5' D= 3'-4' D= 2' -3' D =1' -2' D= 0' -1' EPTH AREA ADJ.AREA ELEV. (15 Min) (FT) (FT) (FT) (FT) (FT) ED (FT) (SF) (SF) (FT) 1 0.000 0.000 0.000 0.000 0.027 0.03 2289.21 2289.21 466.03 INC 2 0.000 0.000 0.000 0.000 0.031 0.03 2294.49 2294.49 466.03 INC 3 0.000 1 0.000 0.000 0.000 0.034 0.03 2299.80 2299.80 466.03 INC 4 0.000 0.000 0.000 0.000 0.038 0.04 2306.27 2306.27 466.04 INC 5 0.000 0.000 0.000 0.000 0.045 0.05 2317.98 2317.98 466.05 INC 6 0.000 0.000 0.000 0.000 0.053 0.05 2329.43 2329.43 466.05 INC 7 0.000 0.000 0.000 0.000 0.060 0.06 2340.63 2340.63 466.06 INC 8 0.000 0.000 0.000 0.000 0.068 0.07 2354.30 2354.30 466.07 INC 9 0.000 0.000 0.000 0.000 0.078 0.08 2370.37 2370.37 466.08 INC 10 0.000 0.000 0.000 0.000 0.090 0.09 2388.83 2388.83 466.09 INC 11 0.000 0.000 0.000 0.000 0.103 0.10 2409.62 2409.62 466.10 INC 12 0.000 0.000 0.000 0.000 0.119 0.12 2435.45 2435.45 466.12 INC 13 0.000 0.000 0.000 0.000 0.139 0.14 2466.26 2466.26 466.14 INC 14 0.000 0.000 0.000 0.000 0.165 0.16 2507.61 2507.61 466.16 INC 15 0.000 0.000 0.000 0.000 0.203 0.20 2568.04 2568.04 466.20 INC 16 0.000 0.000 0.000 0.000 0.248 0.25 2638.81 2638.81 466.25 INC 17 0.000 0.000 0.000 0.000 0.304 0.30 2728.82 2728.82 466.30 INC 18 0.000 0.000 0.000 0.000 0.375 0.38 2841.21 2841.21 466.38 INC 19 0.000 0.000 0.000 0.000 0.458 0.46 2973.00 2973.00 466.46 INC 20 0.000 0.000 0.000 0.000 0.552 0.55 3121.03 3121.03 466.55 INC 21 0.000 0.000 0.000 0.000 0.709 0.71 3370.40 3370.40 466.71 INC 22 0.000 0.000 0.000 0.000 0.954 0.95 3759.72 3759.72 466.95 INC 23 0.000 0.000 0.000 0.000 0.959 0.96 3767.32 3767.32 466.96 PEAK 24 0.000 0.000 0.000 0.000 0.923 0.92 3710.46 3710.46 466.92 1 DEC p.A3.21 STORAGE HYDROGRAPH FOR 100 YEAR / 6 HR STORM RETENTION BASIN. SHEET 2 OF 2 PREPARED BY COACHELLA VALLEY ENGINEERS SUBJECT I Retention D - 6 Hr /100Yr - Trapezoid Retention 4:1 Sideslope JOB # 02226 T.M. 31249, Ave 58 / Coral Mt Ct, West of Madison - La Quinta DATE: 7/7/06 BY: DLC TRIB AREA 1.057 ACRES PERC.RATE 2.00 IN /HR (0.5 IN/15 Min) SOIL GROUP "B ", AMCII, R.I.= 56, R.C. =50 %, STORM VOLUME 2.70 IN /6HR 100 EAR 6 UR A -5. PERIOD PRECIP INTENSITY IMPERV FLOW INFLOW OUTFLOW RETENTION 1 100 C Q VOL115 Min CUML VOL OTHER PERC /15Min OTHER REQD CUML VOL (15min) % (IN /15min) (CFS) (CF) (CF) (CF) (CF) (CF) (CF) RC =50% 1 1.7 0.046 0.474 0.092 82.8 82.8 0.0 95.4 0.0 0.0 2 1.9 0.051 0.476 0.103 92.9 92.9 0.0 95.6 0.0 0.0 3 2.1 0.057 0.478 0.115 103.1 103.1 0.0 95.8 0.0 7.3 4 2.2 0.059 0.479 0.120 108.2 115.5 0.0 96.1 0.0 19.4 5 2.4 0.065 0.481 0.132 118.5 137.9 0.0 96.6 0.0 41.3 6 2.4 1 0.065 0.481 0.132 118.5 159.9 0.0 97.1 0.0 62.8 7 2.4 0.065 0.481 0.132 118.5 181.3 0.0 97.5 0.0 83.8 8 2.5 0.068 0.482 0.137 123.7 207.5 0.0 98.1 0.0 109.4 9 2.6 0.070 0.483 0.143 128.9 238.3 0.0 98.8 0.0 139.6 10 2.7 0.073 0.484 0.149 134.1 273.7 0.0 99.5 0.0 174.1 11 2.8 0.076 0.484 0.155 139.4 313.5 0.0 100.4 0.0 213.1 12 3.0 0.081 0.486 0.167 149.9 363.0 0.0 101.5 0.0 261.5 13 3.2 0.086 0.488 0.178 160.5 422.1 0.0 102.8 0.0 319.3 14 3.6 0.097 0.492 0.202 182.0 501.3 0.0 104.5 0.0 396.8 15 4.3 0.116 0.499 0.245 220.3 617.1 0.0 107.0 0.0 510.1 16 4.7 0.127 0.502 0.270 242.6 752.7 0.0 110.0 0.0 642.7 17 5.4 0.146 0.509 0.314 282.4 925.1 0.0 113.7 0.0 811.4 18 6.2 0.167 0.517 0.366 329.1 1140.5 0.0 118.4 0.0 1022.1 19 6.9 0.186 0.523 0.412 370.9 1393.0 0.0 123.9 0.0 1269.2 20 7.5 0.203 0.529 0.453 407.5 1676.7 0.0 130.0 0.0 1546.6 21 10.6 0.286 0.558 0.675 607.9 2154.5 0.0 140.4 0.0 2014.1 22 14.5 0.392 0.595 0.985_1 886.4 1 2900.5 1 0.0 1 156.7 1 0.0 1 2743.9 23 3.4 0.092 0.490 0.190 171.2 2915.1 0.0 1 157.0 1 0.0 1 2758.1 24 1.0 0.027 0.467 0.053 48.0 2806.1 0.0 1 154.6 1 0.0 1 2651.5 p.A3.22 r r r SUBJECT I JOB # DATE: r r r i■r r r r r rri r lr rr� r r r rr Retention D - 24 Hr /100Yr - Trapezoid Retention 4:1 Sideslope 02226 IT.M. 31249, Ave 58 / Coral Mt Ct, West of Madison - La q SHEET 1 OF 2 7/7/06 BY: DLC WATER SURFACE RETENTION BASIN STORAGE AND DEPTH CALCULATIONS ''. 'r `" - -- DEPTH AREA *" - - -- --- YsT .s��.A`'.� (FT) - - - -- - -I - __ - _ -.... • :� r- - -I- I__.._.. .� � 4 I-- .- ..,-- - - - _._.__ I -� - -- ;�. -t: %' DEPTH AREA AREA CHANGE VOL/FT (Avg) CUML VOL IMPERV RET AREA 000 0., -. 500:0< soo:oX ,000.o y - (FT) (SF) (SF) (CF) (CF) (SF) 0.00 2297.14 2297.14 466.03 INC 2 0.000 D =5.00' 0 0 0 7785 ELEVATION DATA - - -- INC - - -- - - - -- - -- - - - -- - -- .•_....__ D =4.00' 0 0 0 7785 PE Lot46 471.30 D =3.00' 0 0 0 7785 Overflow 469.17 D =2.00' 5659 1827 4746 7785 To Slop 469.17" D =1.00' 3832 1586 3039 3039 CB WS 468.34 �? dr ` 0.08 2376.53 5s • 7 ..7 ' s 1 71. <,ghf�'`•',`.a,.w�iix ontcl2layis��s�s 0.000 0.000 .f•' 0.11 -. � � . c any 2q2 S :.4 i.. 8 z D =0.00' 2246 0.000 0 0 WS 467.10 466.14 INC 9 Rot FIPv ARR -nn 0.000 PERIOD WATER DEPTH WATER SURFACE D= 4' -5' D= 4' -5' D= 4' -5' D= V -2' D= 0' -1' DEPTH AREA ADJ.AREA ELEV. (HR) (FT) (FT) (FT) (FT) (FT) (FT) (SF) (SF) (FT) 1 0.000 0.000 0.000 0.000 0.032 0.03 2297.14 2297.14 466.03 INC 2 0.000 0.000 0.000 0.000 0.035 0.04 2301.59 2301.59 466.04 INC 3 0.000 0.000 0.000 0.000 0.049 0.05 2324.23 2324.23 466.05 INC 4 0.000 0.000 0.000 0.000 0.058 0.06 2338.16 2338.16 466.06 INC 5 0.000 0.000 0.000 0.000 0.079 0.08 2371.64 2371.64 466.08 INC 6 0.000 0.000 0.000 0.000 0.082 0.08 2376.53 2376.53 466.08 INC 7 0.000 0.000 0.000 0.000 0.111 0.11 2421.85 2421.85 466.11 INC 8 0.000 0.000 0.000 0.000 0.137 0.14 2464.05 2464.05 466.14 INC 9 0.000 0.000 0.000 0.000 0.200 0.20 2563.44 2563.44 466.20 INC 10 0.000 0.000 0.000 0.000 0.331 0.33 2770.73 2770.73 466.33 INC 11 0.000 0.000 0.000 0.000 0.403 0.40 2885.20 2885.20 466.40 INC 12 0.000 0.000 0.000 0.000 0.480 0.48 3008.03 3008.03 466.48 INC 13 0.000 0.000 0.000 0.000 0.698 0.70 3352.59 3352.59 466.70 INC 14 0.000 0.000 0.000 0.000 0.923 0.92 3710.48 3710.48 466.92 INC 15 0.000 0.000 0.000 0.054 0.000 1.05 3930.58 3930.58 467.05 INC 16 0.000 0.000 0.000 0.097 0.000 1.10 4010.03 4010.03 467.10 PEAK 17 0.000 0.000 0.000 0.000 0.970 0.97 3784.60 3784.60 466.97 DEC 18 0.000 0.000 0.000 0.000 0.815 0.81 3538.26 3538.26 466.81 DEC 19 0.000 0.000 0.000 0.000 0.656 0.66 3286.09 3286.09 466.66 DEC 20 0.000 0.000 0.000 0.000 0.508 0.51 3051.40 3051.40 466.51 DEC 21 0.000 0.000 0.000 0.000 0.370 0.37 2832.71 2832.71 466.37 DEC 22 0.000 0.000 0.000 0.000 0.241 0.24 2628.66 2628.66 466.24 DEC 23 0.000 0.000 0.000 0.000 0.121 0.12 2437.99 2437.99 466.12 DEC 24 0.000 0.000 0.000 0.000 0.021 0.02 2279.64 2279.64 466.02 DEC p.A3.23 Iii � I� it � Illi! r• +, � I� rr IIIII� illlll� � � r• I• Ir r� STORAGE HYDROGRAPH FOR 100 YEAR 124 HR STORM RETENTION BASIN. SHEET 2 OF 2 PREPARED BY COACHELLA VALLEY ENGINEERS SUBJECT I Retention D - 24 Hr /100Yr - Trapezoid Retention 4:1 Sideslope JOB # 02226 IT.M. 31249, Ave 58 / Coral Mt Ct, West of Madison - La Quinta DATE: 7/7/06 BY: DLC TRIB AREA 1.057 ACRES PERC.RATE 2.00 IN /HR SOIL GROUP "B ", AMCII, R.I.= 32, R.C. =50 %, STORM VOLUME 4.50 IN /24HR - PERIOD PRECIP INTENSITY IMPERV FLOW INFLOW OUTFLOW RETENTION 1 100 C Q VOL /Hr CUML VOL OTHER PERC /Hr OTHER READ CUML VOL (1 Hr) % (IN /Hr) RC =50% (CFS) (CF) (CF) (CF) (CF) (CF) (CF) 0.477 1 1.2 0.054 0.027 98.0 98.0 0.0 382.9 0.0 0.0 2 1.3 0.059 0.478 0.030 106.5 106.5 0.0 383.6 0.0 0.0 3 1.8 0.081 0.486 0.042 149.9 149.9 0.0 387.4 0.0 0.0 4 2.1 0.095 0.491 0.049 176.6 176.6 0.0 389.7 0.0 0.0 5 2.8 0.126 0.502 0.067 240.7 240.7 0.0 395.3 0.0 0.0 6 2.9 0.131 0.504 0.069 250.1 250.1 0.0 396.1 0.0 0.0 7 3.8 0.171 0.518 0.094 337.0 337.0 0.0 403.6 0.0 0.0 8 4.6 0.207 0.530 0.116 417.8 417.8 0.0 410.7 0.0 7.1 9 6.3 0.284 0.557 0.167 601.1 608.3 0.0 427.2 0.0 181.0 10 8.2 0.369 0.587 0.229 824.4 1005.5 0.0 461.8 0.0 543.7 11 7.0 0.315 0.568 0.189 681.1 1224.8 0.0 480.9 0.0 743.9 12 7.3 0.329 0.573 0.199 716.2 1460.1 0.0 501.3 0.0 958.8 13 10.8 0.486 0.628 0.323 1161.6 2120.4 0.0 558.8 0.0 1561.6 14 11.4 0.513 0.638 0.346 1244.5 2806.2 0.0 618.4 0.0 2187.7 15 10.4 0.468 0.622 0.308 1107.3 3295.1 0.0 655.1 0.0 2640.0 16 8.5 0.383 0.592 0.239 861.5 3501.4 0.0 668.3 0.0 2833.1 17 1.4 0.063 0.480 0.032 115.1 2948.2 0.0 630.8 0.0 2317.4 18 1.9 0.086 0.488 0.044 158.7 2476.2 0.0 589.7 0.0 1886.4 19 1.3 0.059 0.478 0.030 106.5 1993.0 0.0 547.7 0.0 1445.3 20 1.2 0.054 0.477 0.027 98.0 1543.3 0.0 508.6 0.0 1034.7 21 1.1 0.050 0.475 0.025 89.5 1124.2 0.0 472.1 0.0 652.1 22 1.0 0.045 0.474 0.023 81.1 733.2 0.0 438.1 0.0 295.1 23 0.9 0.041 0.472 0.020 72.8 367.9 0.0 406.3 0.0 0.0 24 0.8 0.036 1 0.471 0.018 64.5 64.5 0.0 1 379.9 0.0 0.0 p.A3.24 Im m 1=11 IIIIIIINI m m Illy m m 111110111 m i m # m m r A REF: Retention E - 3 Hr /100Yr - Trapezoid Retention 4:1 Sideslope AREA CHANGE VOL/F (Avg) JOB # 02226 T.M. 31249, Ave 58 / Coral Mt Ct, West of Madison - La Quinta (FT) SHEET 1 OF 2 DATE: 7/7/06 (CF) (SF) BY: DLC ADJ.AREA ELEV. (15 Min) (FT) �.- €€S�r,• ca uS }� •I. 0 EA� 1_KyST�ORAGE„� ��Fw'•M:��6. ;r..._V� vii. RETENTION BASIN STORAGE AND DEPTH CALCULATIONS ELEVATION DATA K 0 0 .R_ DEPTH AREA AREA CHANGE VOL/F (Avg) CUML VOL IMPERV RET AREA (FT) (SF) (SF) (CF) (CF) (SF) 0.00 AREA ADJ.AREA ELEV. (15 Min) (FT) D= =5.00' 0 0 0 7231 ELEVATION DATA D =4.00' 0 0 0 7231 PE Lot38 464.00 D =3.00' 0 0 0 7231 Overflow 461.25 D =2.00' 5638 2192 4542 7231 Top Slope 461.60 D =1.00' 3446 1 1515 2689 2689 CB WS 460.42 D =0.00' 1931 0.18 0 0 WS Elev 459.71 INC Bot Elev 458.00 I .P II Y I.. N f I- I i -- , PERIOD WATER DEPTH WATER SURFACE D= 4' -5' D= 3'-4' D= 2' -3' D= 1' -2' D= 0' -1' DEPTH AREA ADJ.AREA ELEV. (15 Min) (FT) (FT) (FT) (FT) (FT) (FT) (SF) (SF) (FT) 1 0.00 0.00 0.00 0.00 0.09 0.09 2069.43 2069.43 458.09 INC 2 0.00 0.00 0.00 0.00 0.18 0.18 2203.41 2203.41 458.18 INC 3 0.00 0.00 0.00 0.00 0.27 0.27 2346:53 2346.53 458.27 INC 4 0.00 0.00 0.00 0.00 0.36 0.36 2478.09 2478.09 458.36 INC 5 0.00 0.00 0.00 0.00 0.49 0.49 2677.67 2677.67 458.49 INC 6 0.00 0.00 0.00 0.00 0.64 0.64 2902.81 2902.81 458.64 INC 7 0.00 0.00 0.00 0.00 0.82 0.82 3171.29 3171.29 458.82 INC 8 0.00 0.00 0.00 0.01 0.00 1.01 3458.49 3458.49 459.01 INC 9 0.00 0.00 0.00 0.18 0.00 1.18 3834.39 3834.39 459.18 INC 10 0.00 0.00 0.00 0.45 0.00 1.45 4439.96 4439.96 459.45 INC 11 0.00 0.00 0.00 0.69 0.00 1.69 4963.44 4963.44 459.69 INC 12 0.00 0.00 0.00 0.71 0.00 1.71 1 5638.00 5638.00 459.71 PEAK p.A3.25 STORAGE HYDROGRAPH FOR 100 YEAR / 3 HR STORM RETENTION BASIN. SHEET 2 OF 2 PREPARED BY COACHELLA VALLEY ENGINEERS SUBJECT I Retention E - 3 Hr /100Yr - Trapezoid Retention 4:1 Sideslope .JOB # 02226 T.M. 31249, Ave 58 / Coral Mt Ct, West of Madison - La Quinta DATE: 7/7/06 BY: DLC TRIG AREA= 1.810 ACRES PERC.RATE 2.00 IN /HR (0..5 IN/15 Min) SOIL GROUP "B ", AMCII, R.I.= 56, R.C. =50 0/67 STORM VOLUME 2.10 IN /3HR 100 A R -5.2 PERIOD PRECIP INTENSITY IMPERV FLOW INFLOW OUTFLOW RETENTION 1 100 C Q VOL /15 Min CUML VOL OTHER PERC /15Min OTHER REQD CUML VOL (15min) % (IN /15min) (CFS) (CF) (CF) (CF) (CF) (CF) (CF) RC =50% 1 3.7 0.078 0.485 0.273 245.7 245.7 0.0 86.2 0.0 159.4 2 4.8 0.101 0.493 0.360 324.0 483.4 0.0 91.8 0.0 391.6 3 5.1 0.107 0.495 0.384 345.8 737.4 0.0 97.8 0.0 639.6 4 4.9 0.103 0.494 0.368 331.2 970.9 0.0 103.3 0.0 867.6 5 6.6 0.139 0.507 0.508 457.4 1325.0 0.0 111.6 0.0 1213.5 6 7.3 0.153 0.512 0.568 511.1 1724.6 0.0 121.0 0.0 1603.6 7 8.4 0.176 0.520 0.664 597.4 2201.0 0.0 132.1 0.0 2068.9 8 9.0 0.189 0.524 0.717 645.5 2714.4 0.0 144.1 0.0 2570.3 9 12.3 0.258 0.548 1.026 923.0 3493.3 0.0 159.8 0.0 3333.5 10 17.6 0.370 0.587 1.572 1414.5 4748.1 0.0 185.0 0.0 4563.1 11 16.1 0.338 0.576 1.411 1269.7 5832.8 0.0 206.8 0.0 5626.0 12 4.2 .0.088 0.489 0.312 281.0 5906.9 0.0 234.9 0.0 5672.0 p.A3.26 711;; 1=111 I11111INIIIII m m m m m m m m m m m m m m m SUBJECT - D= 2' -3' �FµEA�K�.SySORAGE D= 0' -1' DEPTH I Retention E - 6 Hr /100Yr - Trapezoid Retention 4:1 Sideslope ADJ.AREA ELEV. JOB # 02226 T.M. 31249, Ave 58 / Coral Mt Ct, West of Madison - La Quinta (FT) (FT) SHEET 1 OF 2 DATE: 7/7/06 (FT) (SF) (SF) BY: DLC RETENTION BASIN STORAGE AND DEPTH CALCULATIONS 1 0.000 0.000 0.000 0.000 0.053 0.05 2010.90 2010.90 � WATER DEPTH WATER SURFACE D= 4' -5' - D= 2' -3' �FµEA�K�.SySORAGE D= 0' -1' DEPTH AREA ADJ.AREA ELEV. n �""��y�- (15 Min) (FT) (FT) (FT) (FT) (FT) (FT) (SF) (SF) ....::r�':Fb'i�ryrtc�dn 1 0.000 0.000 0.000 0.000 0.053 0.05 2010.90 2010.90 458.05 INC 2 0.000 I L.. 0.000 0.081 sog0.0r. 2053.34 2053.34 458.08 INC I 0.000 1 0.000 0.000 0.000 0.115 0.11 2104.61 2104.61 458.11 INC 4 0.000 4000 0 0.000 0.000 0.151 0.15 2159.62 2159.62 458.15 INC 5 0.000 0.000 0.000 0.000 0.193 0.19 2223.28 2223.28 -.Ea 00 2000 0 INC 6 0.000 0.000 0.000 0.000 0.234 0.23 2285.45 2285.45 458.23 INC 7 0.000 - -- 0.274 0.27 2346.16 2346.16 458.27 INC 8 0.000 0.000 0.000 0.000 0.316 0.32 2410.45 2410.45 458.32 INC 9 ..10000 0.000 0.000 0.000 0.361 0.36 2478.24 2478.24 458.36 INC 10 0.000 0.000 0.000 0.000 0.408 0.41 2549.48 t".�.,t'�1. 458.41 2�,��5�6,'�';8• 11 0.000 0.000 0.000 0.000 0.457 10;1,1.�12��14151617,181920:21 2624.10 2624.10 458.46 INC 12 0.000 223¢4 0.000 0.000 0.512 0.51 2707.13 2707.13 458.51 INC 13 �9 0.000 0.000 0.000 0.573 0.57 2798.46 2798.46 458.57 INC PERIOD WATER DEPTH WATER SURFACE D= 4' -5' D= 3'-4' D= 2' -3' D= 1' -2' D= 0' -1' DEPTH AREA ADJ.AREA ELEV. (15 Min) (FT) (FT) (FT) (FT) (FT) (FT) (SF) (SF) (FT) 1 0.000 0.000 0.000 0.000 0.053 0.05 2010.90 2010.90 458.05 INC 2 0.000 0.000 0.000 0.000 0.081 0.08 2053.34 2053.34 458.08 INC 3 0.000 1 0.000 0.000 0.000 0.115 0.11 2104.61 2104.61 458.11 INC 4 0.000 0.000 0.000 0.000 0.151 0.15 2159.62 2159.62 458.15 INC 5 0.000 0.000 0.000 0.000 0.193 0.19 2223.28 2223.28 458.19 INC 6 0.000 0.000 0.000 0.000 0.234 0.23 2285.45 2285.45 458.23 INC 7 0.000 0.000 0.000 0.000 0.274 0.27 2346.16 2346.16 458.27 INC 8 0.000 0.000 0.000 0.000 0.316 0.32 2410.45 2410.45 458.32 INC 9 0.000 0.000 0.000 0.000 0.361 0.36 2478.24 2478.24 458.36 INC 10 0.000 0.000 0.000 0.000 0.408 0.41 2549.48 2549.48 458.41 INC 11 0.000 0.000 0.000 0.000 0.457 0.46 2624.10 2624.10 458.46 INC 12 0.000 0.000 0.000 0.000 0.512 0.51 2707.13 2707.13 458.51 INC 13 0.000 0.000 0.000 0.000 0.573 0.57 2798.46 2798.46 458.57 INC 14 0.000 0.000 0.000 0.000 0.645 0.65 2908.36 2908.36 458.65 INC 15 0.000 0.000 0.000 0.000 0.740 0.74 3052.64 3052.64 458.74 INC 16 0.000 0.000 0.000 0.000 0.848 0.85 3215.07 3215.07 458.85 INC 17 0.000 0.000 0.000 0.000 0.978 0.98 3412.09 3412.09 458.98 INC 18 0.000 0.000 0.000 0.080 0.000 1.08 3620.29 3620.29 459.08 INC 19 0.000 0.000 0.000 0.186 0.000 1.19 3854.01 3854.01 459.19 INC 20 0.000 0.000 0.000 0.304 0.000 1.30 4113.30 4113.30 459.30 INC 21 0.000 0.000 0.000 0.496 0.000 1.50 4532.94 4532.94 459.50 INC 22 0.000 0.000 0.000 0.788 0.000 1.79 5174.35 5174.35 459.79 INC 23 0.000 0.000 0.000 0.806 0.000 1.81 5211.79 5211.79 459.81 PEAK 24 0.000 0.000 0.000 0.776 0.000 1.78 5146.67 5146.67 459.78 DEC p.A3.27 � 1111011111111 m m m m m m m r m m m m m m m m m m STORAGE HYDROGRAPH FOR 100 YEAR / 6 HR STORM RETENTION BASIN. SHEET 2 OF 2 PREPARED BY COACHELLA VALLEY ENGINEERS SUBJECT I Retention E - 6 Hr /100Yr - Trapezoid Retention 4:1 Sideslope JOB # 02226 T.M. 31249, Ave 58 / Coral Mt Ct, West of Madison - La Quinta DATE: 7/7/06 BY: DLC TRIB AREA 1.810 ACRES PERC.RATE 2.00 IN /HR (0.5 1N/15 Min) SOIL GROUP "B ", AMCII, R.I.= 56, R.C. =50 %, STORM VOLUME 2.70 IN /6HR 100 EAR 6 HOUR PLAT -5.4 PERIOD PRECIP INTENSITY IMPERV FLOW INFLOW OUTFLOW RETENTION 1 100 C Q VOL /15 Min CUML VOL OTHER PERC /15Min OTHER REQD CUML VOL (15min) % (IN /15min) (CFS) (CF) (CF) (CF) (CF) (CF) (CF) RC =50% 1 1.7 0.046 0.474 0.158 141.8 141.8 0.0 83.8 0.0 58.0 2 1.9 0.051 0.476 0.177 159.1 217.1 0.0 85.6 0.0 131.5 3 2.1 0.057 0.478 0.196 176.5 308.1 0.0 87.7 0.0 220.4 4 2.2 0.059 0.479 0.206 185.3 405.7 0.0 90.0 0.0 315.7 5 2.4 0.065 0.481 0.226 203.0 518.7 0.0 92.6 0.0 426.0 6 2.4 0.065 0.481 0.226 203.0 629.0 0.0 95.2 0.0 533.8 7 2.4 0.065 0.481 0.226 203.0 736.7 0.0 97.8 0.0 639.0 8 2.5 0.068 0.482 0.235 211.8 850.8 0.0 100.4 0.0 750.4 9 2.6 0.070 0.483 0.245 220.7 971.1 0.0 103.3 0.0 867.9 10 2.7 0.073 0.484 0.255 229.7 1097.5 0.0 106.2 0.0 991.3 11 2.8 0.076 0.484 0.265 238.6 1230.0 0.0 109.3 0.0 1120.6 12 3.0 0.081 0.486 0.285 256.7 1377.3 0.0 112.8 0.0 1264.5 13 3.2 0.086 0.488 0.305 274.9 1539.4 0.0 116.6 0.0 1422.8 14 3.6 0.097 0.492 0.346 311.6 1734.4 0.0 121.2 0.0 1613.2 15 4.3 0.116 0.499 0.419 377.2 1990.5 0.0 127.2 0.0 1863.3 16 4.7 1 0.127 0.502 0.462 415.4 2278.7 0.0 134.0 0.0 2144.7 17 5.4 0.146 0.509 0.537 483.6 2628.3 0.0 142.2 0.0 2486.2 18 6.2 0.167 0.517 0.626 563.5 3049.6 0.0 150.8 0.0 2898.8 19 6.9 0.186 0.523 0.706 635.1 3533.9 0.0 160.6 0.0 3373.3 20 7.5 0.203 0.529 0.775 697.8 4071.2 0.0 171.4 0.0 3899.8 21 10.6 0.286 0.558 1.157 1040.9 4940.7 0.0 188.9 0.0 4751.9 22 14.5 1 0.392 0.595 1.687 1517.9 6269.8 0.0 215.6 0.0 1 6054.2 23 3.4 0.092 0.490 0.326 293.2 6347.4 0.0 217.2 0.0 6130.2 24 1.0 0.027 0.467 0.091 82.2 6212.4 0.0 214.4 0.0 5998.0 p.A3.28 r llllr Illllr r Ir Illlr r r Illllr Illllr rr rr Illllr Illlr Illlr lllllr r r. Illlr SUBJECT I Retention E - 24 Hr /100Yr - Trapezoid Retention 4:1 Sideslope JOB # 02226 IT.M. 31249, Ave 58 / Coral Mt Ct, West of Madison - La d SHEET 1 OF 2 DATE: 7/7/06 BY: DLC RETENTION BASIN STORAGE AND DEPTH CALCULA ;: % -� MINIM WE STORAGE. PERIOD (5:1 ss) CHANGE (Avg) VOL AREA (FT) (SF) (SF) (CF) (CF) (SF) 0.00 (FT) (FT) (FT) (FT) (FT) (FT) D =5.00' 0 0 0 7231 ELEVATION DATA D =4.00' 0 0 0 7231 PE Lot38 464.00 D =3.00' 0 0 0 7231 Overflow 461.25 D =2.00' 5638 2192 4542 7231 Top Slope 461.60 D =1.00' 3446 1515 2689 2689 CB WS 460.42 D =0.00' 1931 INC 0 0 WS Elev 459.99 0.000 Rnt Flev AsR nn PERIOD WATER DEPTH WATER SURFACE D= 4' -5' D= 4' -5' D= 4' -5' D= V -2' D= 0' -1' DEPTH AREA ADJ.AREA ELEV. (HR) (FT) (FT) (FT) (FT) (FT) (FT) (SF) (SF) (FT) 1 0.000 0.000 0.000 0.000 0.062 0.06 2025.56 2025.56 458.06 INC 2 0.000 0.000 0.000 0.000 0.068 0.07 2033.78 2033.78 458.07 INC 3 0.000 0.000 0.000 0.000 0.095 0.10 2075.65 2075.65 458.10 INC 4 0.000 0.000 0.000 0.000 0.112 0.11 2101.40 2101.40 458.11 INC 5 0.000 0.000 0.000 0.000 0.153 0.15 2163.30 2163.30 458.15 INC 6 0.000 0.000 0.000 0.000 0.179 0.18 2201.47 2201.47 458.18 INC 7 0.000 0.000 0.000 0.000 0.257 0.26 2319.86 2319.86 458.26 INC 8 0.000 0.000 0.000 0.000 0.379 0.38 2505.16 2505.16 458.38 INC 9 0.000 0.000 0.000 0.000 0.607 0.61 2849.94 2849.94 458.61 INC 10 0.000 0.000 0.000 0.000 0.955 0.95 3377.81 3377.81 458.95 INC 11 0.000 0.000 0.000 0.106 0.000 1.11 5638.00 5638.00 459.11 INC 12 0.000 0.000 0.000 0.169 0.000 1.17 5638.00 5638.00 459.17 INC 13 0.000 0.000 0.000 0.400 0.000 1.40 5638.00 5638.00 459.40 INC 14 0.000 0.000 0.000 0.663 0.000 1.66 5638.00 5638.00 459.66 INC 15 0.000 0.000 0.000 0.873 0.000 1.87 5638.00 5638.00 459.87 INC 16 0.000 0.000 0.000 0.991 0.000 1.99 5638.00 5638.00 459.99 PEAK 17 0.000 0.000 0.000 0.828 0.000 1.83 5638.00 5638.00 459.83 DEC 18 0.000 0.000 0.000 0.681 0.000 1.68 5638.00 5638.00 459.68 DEC 19 0.000 0.000 0.000 0.514 0.000 1.51 5638.00 5638.00 459.51 DEC 20 0.000 0.000 0.000 0.344 0.000 1.34 5638.00 5638.00 459.34 DEC 21 0.000 0.000 0.000 0.171 0.000 1.17 5638.00 5638.00 459.17 DEC 22 0.000 0.000 0.000 0.000 0.991 0.99 3432.11 3432.11 458.99 DEC 23 0.000 0.000 0.000 0.000 0.824 0.82 3179.99 3179.99 458.82 DEC 24 0.000 1 0.000 0.000 0.000 0.668 0.67 2943.54 2943.54 458.67 DEC p.A3.29 m � � � � � IM m � � m m m m m m m m STORAGE HYDROGRAPH FOR 100 YEAR / 24 HR STORM RETENTION BASIN. SHEET 2 OF 2 PREPARED BY COACHELLA VALLEY ENGINEERS SUBJECT I Retention E - 24 Hr /100Yr - Trapezoid Retention 4:1 Sideslope JOB # 02226 IT.M. 31249, Ave 58 / Coral Mt Ct, West of Madison - La Quinta DATE: 7/7/06 BY: DLC TRIB AREA 1.810 ACRES PERC.RATE 2.00 IN /HR SOIL GROUP "B ", AMCII, R.I.= 56, R.C. =50 %, STORM VOLUME 4.50 IN /24HR - PERIOD PRECIP INTENSITY IMPERV FLOW INFLOW OUTFLOW RETENTION 1 100 C Q VOL /Hr CUML VOL OTHER PERC /Hr OTHER REQD CUML VOL (1 Hr) % (IN /Hr) RC =50% (CFS) (CF) (CF) (CF) (CF) (CF) (CF) 0.477 1 1.2 0.054 0.047 167.8 167.8 0.0 337.6 0.0 0.0 2 1.3 0.059 0.478 0.051 182.4 182.4 0.0 339.0 0.0 0.0 3 1.8 0.081 0.486 0.071 256.7 256.7 0.0 345.9 0.0 0.0 4 2.1 0.095 0.491 0.084 302.4 302.4 0.0 350.2 0.0 0.0 5 2.8 0.126 0.502 0.115 412.2 412.2 0.0 360.5 0.0 51.7 6 2.9 0.131 0.504 1 0.119 428.3 480.0 0.0 366.9 0.0 113.1 7 3.8 0.171 0.518 0.160 577.0 690.1 0.0 386.6 0.0 303.4 8 4.6 0.207 0.530 0.199 715.5 1018.9 0.0 417.5 0.0 601.4 9 6.3 0.284 0.557 0.286 1029.4 1630.7 0.0 475.0 0.0 1155.7 10 8.2 0.369 0.587 0.392 1411.7 2567.5 0.0 563.0 0.0 2004.5 11 7.0 0.315 0.568 0.324 1166.4 3170.9 0.0 939.7 0.0 2231.2 12 7.3 1 0.329 0.573 0.341 1226.5 3457.7 0.0 939.7 0.0 2518.0 13 10.8 0.486 0.628 0.553 1989.1 4507.1 0.0 939.7 0.0 3567.4 14 11.4 0.513 0.638 0.592 2131.1 5698.5 0.0 939.7 0.0 4758.9 15 10.4 0.468 0.622 0.527 1896.2 6655.0 0.0 939.7 0.0 5715.4 16 8.5 0.383 0.592 0.410 1475.2 7190.5 0.0 939.7 0.0 6250.9 17 1.4 0.063 0.480 0.055 197.1 6447.9 0.0 939.7 0.0 5508.3 18 1.9 0.086 0.488 0.076 271.8 5780.1 0.0 939.7 0.0 4840.4 19 1.3 0.059 0.478 0.051 182.4 5022.8 0.0 939.7 0.0 4083.2 20 1.2 0.054 0.477 0.047 167.8 4251.0 0.0 939.7 0.0 3311.3 21 1.1 0.050 0.475 0.043 153.3 3464.6 0.0 939.7 0.0 2524.9 22 1.0 0.045 0.474 0.039 138.9 2663.9 0.0 572.0 0.0 2091.8 23 0.9 0.041 0.472 0.035 124.6 2216.4 0.0 530.0 0.0 1686.4 24 0.8 0.036 0.471 0.031 110.4 1 1796.8 1 0.0 1 490.6 1 0.0 1306.2 p.A3.30 � 1=1 IM 1=1 1=1 M 1=1 M I♦ M M M M 1=1 M M M M 1=1 M BASIN E - 02226 EHLINE TIME OF CONCENTRATION: INITIAL FLOW: Ti = k *(L ^3/h) ^.2 where: k = 0.39 L, length of initial flow = 100 Ave 58 h, elevation difference over initial flow = 0.86 Ti = 6.37 minutes STREET CAPACITY: Q= 1.486 *A *R ^2 /3 *S ^1/2 n LN Tc = Ti + Ts where: 13.77 min. A, X- sectional area of street = 7.76 sf Wetted perimeter = 55.91 R = 0.13879 S, slope = 0.0084 ft/ft n, Mannings coefficient = 0.017 Q = 16.66 cfs VELOCITY. in Street: V= Q/A where: Q, capacity, cfs = 16.66 A, area, sf = . 7.76 V = 2.15 fps CVE 7/18/2006 STREET FLOW: Ts = LN Tc = Ti + Ts where: 13.77 min. L, length of flow = 954 V, street velocity = 2.15 Ts = 444.24 secs 7.40 min. DESIGN Q1o: Q10 = C *I *A where: C, runoff coefficient = 0.7641 (From Plate D -5.7) I, rainfall intensity = 2.353 in /hr (10yr - From Plate D -4.1) (Palm Springs) A, drainage area = 1.917 AC (Drainage Map) Q10 = 3.45 cfs DESIGN Q1oo: Q10o = where: C, runoff coefficient = I, rainfall intensity = A, drainage area = Q10o = C *I *A 0.8051 (From Plate D -5.7) 3.757 in /hr (100yr - From Plate D -4.1) (Palm Springs) 1.917 AC (Drainage Map) 5.80 cfs 060712 02226 FORMULAS RATIONAL.As Page 9 of 10 BASIN E - 02226 EHLINE CATCH BASIN DESIGN: BASED ON 10YR. STORM CB #1 Q10 = C *I *A C, runoff coefficient = 0.7641 (From Plate D -5.7) I, rainfall intensity = 2.353 in /hr (10yr - From Plate D -4.1) A, drainage area = 0.236 AC (Drainage Map) Q10 = 0.42 cfs CB #2 Q10 = C *I *A C, runoff coefficient = 0.7641 (From Plate D -5.7) I, rainfall intensity = 2 ,353 in /hr (10yr - From Plate D -4.1) A, drainage area = 0.072 AC (Drainage Map) Q10 = 0.13 cfs C13#11 Q10 = C *I *A C, runoff coefficient = 0.7641 (From Plate D -5.7) I, rainfall intensity = 2.353 in /hr (10yr - From Plate D -4.1) A, drainage area = 1.609 AC (Drainage Map) Q10 = 2.89 cfs CATCH BASIN FORMULA (Los Angeles County Flood Control District, D -25) Q= C *W ^.83 *D ^2 Where, Q = Flow to Catch Basin, cfs(10yr Storm) C = 3.25 D = Depth of flow = 10" (0.83') W = Length of C.B. Opening CB #1 Q100 = C *I *A C, runoff coefficient = I, rainfall intensity = A, drainage area = Q100 = CB #2 C, runoff coefficient = I, rainfall intensity = A, drainage area = Q100 = CVE 7/18/2006 0.805 (From Plate D -5.7) 3.757 in /hr (100yr - From Plate D -4.1) 0.236 AC (Drainage Map) 0.71 cfs Q100 = C *I *A 0.805 (From Plate D -5.7) 3.757 in /hr (100yr - From Plate D -4.1) 0.072 AC (Drainage Map) 0.22 cfs CB #11 Q1oo = C *I *A C, runoff coefficient = 0.805 (From Plate D -5.7) I, rainfall intensity = 3.757 in /hr (100yr - From Plate D -4.1) A, drainage area = 1.609 AC (Drainage Map) Q100 = 4.87 cfs 060712 02226 FORMULAS RATIONAL.As Page 10 of 10 BASED ON 10YR. STORM W = 0.13 ft. #1 Use 4.0' W = 0.03 ft. #2 Use 4.0' W = 4.46 ft. #3 Use 5.0' W = 1.74 ft. #4 Use 4.0' W = 2.90 ft. #5 Use 4.0' W = 5.26 ft. #6 Use 6.0' W = 0.77 ft. #7 Use 4.0' W = 5.21 ft. #8 Use 6.0' W = 1.57 ft. #9 Use 4.0' W = 0.71 ft. #10 Use 4.0' W = 1.36 ft. #11 Use 4.0' 060712 02226 FORMULAS RATIONAL.As Page 10 of 10 I w ■■1 M M 1=1 1=11 M M M M M M M M M M a M BASIN A - 02226 EHLINE TIME OF CONCENTRATION: INITIAL FLOW: Ti = k *(L ^3/h) ^.2 where: k = 0.39 L, length of initial flow = 105 Mtn View Circle h, elevation difference over initial flow = 2.8 Ti = 5.18 minutes STREET CAPACITY: (1/2 Street) Q= 1.486 *A *R ^2 /3 *S ^1/2 n W Tc = Ti + Ts where: 12.76 min. A, X- sectional area of street = 2.21 sf Wetted perimeter = 15.6 R = 0.1417 S, slope = 0.0075 ft/ft n, Mannings coefficient = 0.017 Q = 4.55 cfs VELOCITY. in Street: V= Q/A where: Q, capacity, cfs = 4.55 A, area, sf = 2.21 V = 2.06 fps 060712 02226 FORMULAS RATIONAL.As STREET FLOW: Ts = W Tc = Ti + Ts where: 12.76 min. L, length of flow = 936 V, street velocity = 2.06 Ts = 455.01 secs 7.58 min. DESIGN Q1o: Q10 = C *I *A where: C, runoff coefficient = 0.7683 (From Plate D -5.7) I, rainfall intensity = 2.457 in /hr (10yr - From Plate D- (Palm Springs) A, drainage area = 8.846 AC (Drainage Map) Q 10 = 16.70 cfs DESIGN Q1oo: Q1oo = C *I *A where: C, runoff coefficient = 0.8085 (From Plate D -5.7) I, rainfall intensity = 3.925 in /hr (100yr - From Plate C (Palm Springs) A, drainage area = 8.846 AC (Drainage Map) Q100 = 28.07 cfs p.A4.1 CVE 7/12/06 Im M M M M s M iM r M 11 M M M M M M M M CATCH BASIN DESIGN: CB #3 Q10 = C *I *A C, runoff coefficient = 0.7683 (From Plate D -5.7) I, rainfall intensity = 2.457 in /hr (10yr - From Plate D -4.1) A, drainage area = 4.1 AC (Drainage Map) Q10 = 7.74 cfs CB #4 Q10 = C *I *A C, runoff coefficient = 0.7683 (From Plate D -5.7) I, rainfall intensity = 2.457 in /hr (10yr -From Plate D -4.1) A, drainage area = 1.$8 AC (Drainage Map) Q10 = 3.55 cfs CB #5 Q10 = C *I *A C, runoff coefficient = 0.7683 (From Plate D -5.7) I, rainfall intensity = 2.457 in /hr (10yr - From Plate D -4.1) A, drainage area = 2.87 AC (Drainage Map) Q10 = 5.41 cfs p.A4.2 060712 02226 FORMULAS RATIONAL.As CB #3 Q1oo = C *I *A C, runoff coefficient = 0.809 (From Plate D -5.7) I, rainfall intensity = 3.925 in /hr (100yr - From Plate D -4.1) A, drainage area = 4.1 AC (Drainage Map) Q100 = 13.01 cfs CB #4 Q1oo = C *I *A C, runoff coefficient = 0.809 (From Plate D -5.7) I, rainfall intensity = 3.925 in /hr (100yr - From Plate D -4.1) A, drainage area = 1.88 AC (Drainage Map) Q100 = 5.97 cfs CB #5 Q1oo = C *I *A C, runoff coefficient = 0.809 (From Plate D -5.7) I, rainfall intensity = 3.925 in /hr (100yr - From Plate D -4.1) A, drainage area = 2.866 AC (Drainage Map) Q100 = 9.09 cfs CVE 7/12/06 FM M M a M i M M r i M11=1 M M M M MIMI =11 BASIN B - 02226 EHLINE TIME OF CONCENTRATION: INITIAL FLOW: Ti = k *(L ^3/h) ^.2 where: k = 0.39 L, length of initial flow = 231 h, elevation difference over initial flow = 1.1 Ti = 10.02 minutes STREET CAPACITY: (1/2 Street) Q= 1.486 *A *R ^2 /3 *S ^1/2 n where: A, X- sectional area of street = 2.21 sf Wetted perimeter = 15.61 R = 0.1416 S, slope = 0.0100 ft/ft n, Mannings coefficient = 0.017 Q = 5.25 cfs VELOCITY. in Street: V= Q/A where: Q, capacity, cfs = 5.25 A, area, sf = 2.21 V = 2.37 fps CVE 7/12/06 STREET FLOW: Ts = LN Tc = Ti + Ts where: 15.34 min. L, length of flow = 757 V. street velocity = 2.37 Ts = 318.83 secs 5.31 min. DESIGN Q1o: Q10 = C *I *A where: C, runoff coefficient = 0.7581 (From Plate D -5.7) I, rainfall intensity = 2.203 in /hr (10yr - From Plate D -4.1) (Palm Springs) A, drainage area = 6.394 AC (Drainage Map) Q10 = 10.68 cfs DESIGN Q1oo: Q10o = where: C, runoff coefficient = I, rainfall intensity = A, drainage area = Q1oo = p.A4.3 C *I *A 0.8006 (From Plate D -5.7) 3.532 in /hr (100yr - From Plate D -4.' (Palm Springs) 6.394 AC (Drainage Map) 18.08 cfs 060712 02226 FORMULAS RATIONAL.As Page 1 of 2 CATCH BASIN DESIGN: CB #6 C, runoff coefficient = I, rainfall intensity = A, drainage area = Q10 = CB #7 C, runoff coefficient = I, rainfall intensity = A, drainage area = Q10 = Q10 = C *I *A 0.7581 (From Plate D -5.7) 2.203 in /hr (10yr - From Plate D -4.1) 5.318 AC (Drainage Map) 8.88 cfs Q10 = C *I *A 0.7581 (From Plate D -5.7) 2.203 in /hr (10yr - From Plate D -4.1) 1.076 AC (Drainage Map) 1.80 cfs p.A4.4 CVE 060712 02226 FORMULAS RATIONAL.As Page 2 of 2 7/12/06 CB #6 Q1oo = C *I *A C, runoff coefficient = 0.801 (From Plate D -5.7) I, rainfall intensity = 3.532 in /hr (100yr - From Plate D -4.1) A, drainage area = 5.318 AC (Drainage Map) Q100 = 15.04 cfs CB #7 Q1oo = C *I *A C, runoff coefficient = 0.801 (From Plate D -5.7) I, rainfall intensity = 3.532 in /hr (100yr - From Plate D -4.1) A, drainage area = 1.076 AC (Drainage Map) Q100 = 3.04 cfs 060712 02226 FORMULAS RATIONAL.As Page 2 of 2 Im w w M w M M w w w w w w w w w w w w BASIN C - 02226 EHLINE TIME OF CONCENTRATION: INITIAL FLOW: Ti = k *(L ^3/h) ".2 where: k = 0.39 L, length of initial flow = 231 h, elevation difference over initial flow = 3.35 Ti = 8.02 minutes STREET CAPACITY: (1/2 Width) Q= 1.486 *A *R ^2 /3 *S ^1/2 n where: A, X- sectional area of street = 2.21 sf Wetted perimeter = 15.6 R = 0.1417 S, slope = 0.0130 ft/ft n, Mannings coefficient = 0.017 Q = 5.99 cfs VELOCITY. in Street: V= Q/A where: Q, capacity, cfs = 5.99 A, area, sf = 2.21 V = 2.71 fps STREET FLOW: Ts = L/V Tc = Ti + Ts where: 13.83 min. L, length of flow = 944 V, street velocity = 2.71 Ts = 348.56 secs 5.81 min. DESIGN Q1o: Q10 = C *I *A where: C, runoff coefficient = 0.7639 (From Plate D -5.7) I, rainfall intensity = 2.347 in /hr (10yr - From Plate D -, (Palm Springs) A, drainage area = 6.726 AC (Drainage Map) Q10 = 12.06 cfs DESIGN Qioo: Q100 = where: C, runoff coefficient = I, rainfall intensity = A, drainage area = Q100 = p.A4.5 C *I *A 0.8049 (From Plate D -5.7) 3.747 in /hr (100yr - From Plate D (Palm Springs) 6.726 AC (Drainage Map) 20.29 cfs CVE 7/12/06 060712 02226 FORMULAS RATIONAL.As Page 1 of 2 � M 1=1 M M M M M M M M M 1=11 r r M M M r M BASIN C - 02226 EHLINE CATCH BASIN DESIGN: CB #8 C, runoff coefficient = I, rainfall intensity = A, drainage area = Q10 = CB #9 C, runoff coefficient = I, rainfall intensity = A, drainage area = Q10 = Q10 = C *I *A 0.7639 (From Plate D -5.7) 2.347 in /hr (10yr - From Plate D -4.1) 4.914 AC (Drainage Map) 8.81 cfs Q10 = C *I *A 0.7639 (From Plate D -5.7) 2.347 in /hr (10yr - From Plate D -4.1) 1.812 AC (Drainage Map) 3.25 cfs p.A4.6 CB #8 C, runoff coefficient = I, rainfall intensity = A, drainage area = Q100 = CB #9 C, runoff coefficient = I, rainfall intensity = A, drainage area = Q100 = Q1oo = C *I *A 0.805 (From Plate D -5.7) 3.747 in /hr (100yr - From Plate D -4.1) 4.914 AC (Drainage Map) 14.82 cfs Q1oo = C *I *A 0.805 (From Plate D -5.7) 3.747 in /hr (100yr - From Plate D -4.1) 1.812 AC (Drainage Map) 5.46 cfs CVE 7/12/06 060712 02226 FORMULAS RATIONAL.As Page 2 of 2 Q = 31:75 cfs VELOCITY. in Street: V= Q/A where: Q, capacity, cfs = 31.75 A, area, sf = 8.05 V = 3.94 fps p.A4.12 060607 02226 STREET CAPACITYAs STREET CAPACITY: SEGOVIA VIEW WAY - D.A. #21 & #22 CVE From the west to CB #8 & #9 7/18/2006 TIME OF CONCENTRATION: INITIAL FLOW: STREET FLOW: Ti = k *(L "3/h) ^.2 Ts = LN Tc = Ti + Ts where: k = 0.39 where: 12.05 min. L, length of initial flow = 233 Segovia View Way L, length of flow = 944 h, elevation difference over initial flow = 3.35 V, street velocity = 3.94 Ti = 8.06 minutes Ts = 239.33 secs 3.99 min. STREET CAPACITY: SEGOVIA VIEW WAY DESIGN Qloo: Q= 1.486 *A *R ^2 /3 *S ^1/2 Qloo = C *I *A n where: where: A, X- sectional area of street = 8.05 sf C, runoff coefficient = 0.8107 (From Plate D -5.7) Wetted perimeter = 32.33 I, rainfall intensity = 4.0681 in /hr (10yr - From Plate D -4.1) (Palm Springs) R = 0.24899 A, drainage area = 5.36 AC (Drainage Map) S, slope = 0.0130 ft/ft n, Mannings coefficient = 0.017 Q100 = 17.68 cfs O.K. Q = 31:75 cfs VELOCITY. in Street: V= Q/A where: Q, capacity, cfs = 31.75 A, area, sf = 8.05 V = 3.94 fps p.A4.12 060607 02226 STREET CAPACITYAs STREET CAPACITY: SEGOVIA VIEW WAY - D.A. #23 & #24 From the east to CB #8 & #9 TIME OF CONCENTRATION: INITIAL FLOW: Ti = k *(L ^3/h) ^.2 where: k = 0.39 L, length of initial flow = 161 Segovia View Way h, elevation difference over initial flow = 0.9 Ti = 8.40 minutes STREET CAPACITY: SEGOVIA VIEW WAY Q= 1.486 *A *R ^2 /3 *S ^1/2 n where: A, X- sectional area of street = 8.05 sf Wetted perimeter = 32.33 R = 0.24899 S, slope = 0.0050 ft/ft n, Mannings coefficient = 0.017 Q = 19.69 cfs VELOCITY. in Street: V= Q/A where: Q, capacity, cfs = 19.69 A, area, sf = 8.05 V = 2.45 fps 060607 02226 STREET CAPACITYAS CVE 7/18/2006 STREET FLOW: Ts = L/V Tc = Ti + Ts where:. 9.48 min. L, length of flow = 158 V, street velocity = 2.45 Ts = 64.59 secs 1.08 min. DESIGN Qloo: Qioo = C *I *A where: C, runoff coefficient = 0.8167 (From Plate D -5.7) I, rainfall intensity = 4.671 in /hr (10yr - From Plate D -4.1) (Palm Springs) A, drainage area = 1.37 AC (Drainage Map) Q100 = 5.23 cfs 0. K. p.A4.13 STREET CAPACITY: PALATINE CIRCLE - D.A. #1 & #2 From the west to Aragon Way TIME OF CONCENTRATION: INITIAL FLOW: Ti = k *(L ^3/h) ^.2 where: k = 0.39 L, length of initial flow = 105 Palatine Circle h, elevation difference over initial flow = 2.8 Ti = 5.18 minutes STREET CAPACITY: SEGOVIA VIEW WAY Q= 1.486 *A *R ^2 /3 *S ^1/2 n where: A, X- sectional area of street = 8.05 sf Wetted perimeter = 32.33 R = 0.24899 S, slope = 0.0075 ft/ft n, Mannings coefficient = 0.017 Q = 24.12 cfs VELOCITY. in Street: V= Q/A where: Q, capacity, cfs = 24.12 A, area, sf = 8.05 V = 3.00 fps 060607 02226 STREET CAPACITYAs CVE 7/18/2006 STREET FLOW: Ts = L/V Tc = Ti + Ts where: 8.67 min. L, length of flow = 627 V, street velocity = 3.00 Ts = 209.28 secs 3.49 min. DESIGN Qloo: Qloo = C *I *A where: C, runoff coefficient = 0.8192 (From Plate D -5.7) I, rainfall intensity = 4.922 in /hr (10yr - From Plate D -4.1) (Palm Springs) A, drainage area = 2.41 AC (Drainage Map) Q100 = 9.72 cfs O.K. p.A4.14 111IMMM IM M MIMI iM M M Il♦ M M Is M m m m M STREET CAPACITY: VERA CRUZ COURT - D.A. #13 & #14 From the north to Carol View Way TIME OF CONCENTRATION: INITIAL FLOW: Ti = k *(L ^3/h) ^.2 where: k = 0.39 L, length of initial flow = 215 Vera Cruz Ct. h, elevation difference over initial flow = 1.27 Ti = 9.33 minutes STREET CAPACITY: SEGOVIA VIEW WAY Q= 1.486 *A *R ^2 /3 *S ^1/2 n L/V Tc = Ti + Ts where: 11.72 min. A, X- sectional area of street = 8.05 sf Wetted perimeter = 32.33 R = 0.24899 S, slope = 0.0050 ft/ft n, Mannings coefficient = 0.017 Q = 19.69 cfs VELOCITY. in Street: V= Q/A where: Q, capacity, cfs = 19.69 A, area, sf = 8.05 V = 2.45 fps 060607 02226 STREET CAPACITY.As CVE 7/18/2006 STREET FLOW: Ts = L/V Tc = Ti + Ts where: 11.72 min. L, length of flow = 351 V, street velocity = 2.45 Ts = 143.49 secs 2.39 min. DESIGN Qloo: Qioo = C *I *A where: C, runoff coefficient = 0.8013 (From Plate D -5.7) I, rainfall intensity = 4.129 in /hr (10yr - From Plate D -4.1) (Palm Springs) A, drainage area = 2.54 AC (Drainage Map) Q100 = 8.40 cfs O.K. p.A4.15 � M M M 1=1 M M M M M M M M M M M M M r M STREET CAPACITY: CAROL VIEW WAY(W) - D.A. #11 & #12 From the south to CB #6 & #7 TIME OF CONCENTRATION: INITIAL FLOW: Ti = k *(L ^3/h) ^.2 where: k = 0.39 L, length of initial flow = 48 Carol View Way h, elevation difference over initial flow = 0.96 Ti = 4.01 minutes STREET CAPACITY: SEGOVIA VIEW WAY Q= 1.486 *A *R ^2 /3 *S ^1/2 n L/V Tc = Ti + Ts where: 7.66 min. A, X- sectional area of street = 8.05 sf Wetted perimeter = 32.33 R = 0.24899 S, slope = 0.0100 ft/ft n, Mannings coefficient = 0.017 Q = 27.85 cfs VELOCITY. in Street: V= Q/A where: Q, capacity, cfs = 27.85 A, area, sf = 8.05 V = 3.46 fps 060607 02226 STREET CAPACITY.As CVE 7/18/2006 STREET FLOW: Ts = L/V Tc = Ti + Ts where: 7.66 min. L, length of flow = 757 V, street velocity = 3.46 Ts = 218.82 secs 3.65 min. DESIGN Qloo: Qloo = C *I *A where: C, runoff coefficient = 0.8229 (From Plate D -5.7) I, rainfall intensity = 5.289 in /hr (10yr - From Plate D -4.1) (Palm Springs) A, drainage area = 2.88 AC (Drainage Map) Qloo = 12.53 cfs Carol View Way Q100 = 8.4 cfs Vera Cruz Court 20.93 O.K. p.A4.16 11=1 M M i M M M M M M M M M M M M M M M STREET CAPACITY: CAROL VIEW WAY(E) - D.A. #16 & #17 From the west to CB #1 & #3 TIME OF CONCENTRATION: INITIAL FLOW: Ti = k *(L ^3/h) ^.2 where: k = 0.39 L, length of initial flow = 250 Carol View Way h, elevation difference over initial flow = 0.94 Ti = 10.84 minutes STREET CAPACITY: SEGOVIA VIEW WAY Q= 1.486 *A *R ^2 /3 *S ^1/2 n L/V Tc = Ti + Ts where: 13.60 min. A, X- sectional area of street = 8.05 sf Wetted perimeter = 32.33 R = 0.24899 S, slope = 0.0140 ft/ft n, Mannings coefficient = 0.017 Q = 32.95 cfs VELOCITY. in Street: V= Q/A where: Q, capacity, cfs = 32.95 A, area, sf = 8.05 V = 4.09 fps 060607 02226 STREET CAPACITY.As CVE 7/18/2006 STREET FLOW: Ts = L/V Tc = Ti + Ts where: 13.60 min. L, length of flow = 678 V, street velocity = 4.09 Ts = 165.64 secs 2.76 min. DESIGN Qloo: Qloo = C *I *A where: C, runoff coefficient = 0.8057 (From Plate D -53) I, rainfall intensity = 3.784 in /hr (10yr - From Plate D -4.1) (Palm Springs) A, drainage area = 3.93 AC (Drainage Map) Q100 = 11.98 cfs O.K. p.A4.17 m m � m � i � m m m m m m m m m m m m Project: Ehline PN: 02226 BY: DLC STORM DRAIN DESIGN PREPARED BY COACHELLA VALLEY ENGINEERS "'BASED ON 100 YEAR STORM "" DATE: 07/20/06 **REVISED** ISTORM DRAIN LINE: "PH. -A" PIPE / OUTLET DESIGN (MAXWELL PLUS) DIA.(IN) Q100(CFS) 30 20.28 SLOPE OF PIPE 0.0210 ft/ft CAPACITY: Q100(CFS): HGL CALCULATIONS, PARTIAL DEPTH WATER DEPTH (Q100) IN PIPE 11.566 in VELOCITY @ Q100 11.62 fps TYPE OF PIPE HDPE DEPTH CHECK FOR CATCH BASIN NO. 9 Q100 TO OPENING (CFS) 5.46 TC AT OPENING 463.95 VS HGL 463.31 OK CONFL.Q100(CFS) 20.28 STORM DRAIN LINE: ' H.II -B PIPE DIA.(IN) Q100(CFS) 24 14.82 SLOPE OF PIPE 0.0050 ft/ft HGL CALCULATIONS, PARTIAL DEPTH WATER DEPTH (Q100) IN PIPE 17.078 in VELOCITY @ Q100 6.20 fps TYPE OF PIPE HDPE DEPTH CHECK FOR CATCH BASIN NO. 8 Q100 TO OPENING (CFS) 14.82 TC AT OPENING 463.98 VS HGL 462.27 OK p.A4.23 C: \Documents and Settings \DRice \Local Settings \Temporary Internet Files \OLK73 \02226 SD_HGL_X.xls VELOCITY HEAD CAPACITY: Q100(CFS): VELOCITY HEAD 59.44 cfs 20.28 cfs OK ELEV. IN PIPE, CB #9 460.25 Depth in Pipe at Q100(ft) 0.96 HV= V2 /2G= • 2.10 SPECIFIC ENERGY 3.06 HGL AT U.S.END= 463.31 15.99 cfs 14.82 cfs OK ELEV. IN PIPE, CB #9 460.25 Depth in Pipe at Q100(ft) 1.42 HV= V2 12G= 0.60 SPECIFIC ENERGY 2.02 HGL AT U.S.END= 462.27 r r r rr� ar r rr r r �r r r r rr �r rr rr �■r �■r Project: Ehline PN: 02226 BY: DLC STORM DRAIN DESIGN PREPARED BY COACHELLA VALLEY ENGINEERS "`BASED ON 100 YEAR STORM' DATE: 7/20/06 "REVISED" PIPE STORM DRAIN LINE: "B" DIA.(IN) Q100(CFS) OUTLET DESIGN (MAXWELL PLUS) 27 18.08 SLOPE OF PIPE 0.0200 ft/ft CAPACITY: 43.79 cfs Q100(CFS): 18.08 cfs OK HGL CALCULATIONS, PARTIAL DEPTH ELEV. IN PIPE, CB #7 463.73 WATER DEPTH (Q100) IN PIPE 9.025 in Depth in Pipe at Q100(ft) 0.75 VELOCITY @ Q100 15.52 fps VELOCITY HEAD HV= V2 /2G= 3.74 TYPE OF PIPE HDPE SPECIFIC ENERGY 4.49 HGL AT U.S.END= 468.22 DEPTH CHECK FOR CATCH BASIN NO. 7 Q100 TO OPENING (CFS) 3.04 TC AT OPENING 468.93 VS HGL 468.22 OK CONFL.Q100(CFS) 18.08 STORM DRAIN LINE: "A" PIPE DIA.(IN) Q100(CFS) 27 15.04 SLOPE OF PIPE 0.0050 ft/ft CAPACITY:. 21.90 cfs Q100(CFS): 15.04 cfs OK . HGL CALCULATIONS, PARTIAL DEPTH j ELEV. IN PIPE, CB #6 465.57 WATER DEPTH (0100) IN PIPE 15.605 in Depth in Pipe at Q100(ft) 1.30 VELOCITY Q100 @ 6.32 fps p VELOCITY HEAD = HV V2 /2G 0.62 TYPE OF PIPE HDPE SPECIFIC ENERGY 1.92 HGL AT U.S.END= 467.49 DEPTH CHECK FOR CATCH BASIN NO. 6 Q100 TO OPENING (CFS) 15.04 TC AT OPENING 468.93 VS HGL 467.49 OK p.A4.19 C: \Documents and Settings \DRice \Local Settings \Temporary Internet Files \OLK73 \02226 SD_HGL_X.xls m m m r m m� m m m� m m m m m m m m 'Project: Ehline PN: 02226 BY: DLC STORM DRAIN DESIGN PREPARED BY COACHELLA VALLEY ENGINEERS ** *BASED ON 100 YEAR STORM * ** DATE: 07/20/06 * *REVISED ** PIPE STORM DRAIN LINE: "C" DIA.(IN) Q100(CFS) OUTLET DESIGN (MAXWELL PLUS) 1 42 28.07 1 SLOPE OF PIPE 0.0310 ft/ft HGL CALCULATIONS, PARTIAL DEPTH WATER DEPTH (Q100) IN PIPE 10.846 in VELOCITY @ Q100 14.26 fps TYPE OF PIPE HDPE DEPTH CHECK FOR CATCH BASIN NO. 3 Q100 TO OPENING (CFS) 13.01 TC AT OPENING 462.27 VS HGL 461.71 OK CONFL.Q100(CFS) 28.07 STORM DRAIN LINE: "D' IPIPE DIA.(IN) Q100(CFS) 30 15.06 SLOPE OF PIPE 0.0070 ft/ft HGL CALCULATIONS, PARTIAL DEPTH WATER DEPTH (Q100) IN PIPE 13.289 in VELOCITY @ Q100 7.18 fps TYPE OF PIPE HDPE DEPTH CHECK FOR CATCH BASIN NO. 4 Q100 TO OPENING (CFS) 5.97 TC AT OPENING 462.02 VS HGL 460.07 OK CONFL.Q100(CFS) 15.06 p.A4.20 C: \Documents and Settings \DRice \Local Settings \Temporary Internet Files \OLK73 \02226 SD_HGL_X.xls CAPACITY: 177.15 cfs Q100(CFS): 28.07 cfs OK ELEV. IN PIPE, CB #3 457.65 Depth in Pipe at Q100(ft) 0.90 VELOCITY HEAD HV= V2 /2G= 3.16 SPECIFIC ENERGY 4.060 HGL AT U.S.END= 461.71 CAPACITY: 34.32 cfs Q100(CFS): 5.97 cfs OK ELEV. IN PIPE, CB#4 458.16 Depth in Pipe at Q100(ft) 1.11 VELOCITY HEAD HV= V2 /2G= 0.80 SPECIFIC ENERGY 1.91 HGL AT U.S.END= 460.07 Project: Ehline PN: 02226 BY: DLC STORM DRAIN LINE: "E" PIPE DIA.(IN) Q100(CFS) 30 9.09 SLOPE OF PIPE 0.0050 ft/ft CAPACITY: 29.00 cfs Q100(CFS): 9.09 cfs OK HGL CALCULATIONS, PARTIAL DEPTH WATER DEPTH (Q100) IN PIPE 11.049 in VELOCITY @ Q100 5.54 fps TYPE OF PIPE HDPE DEPTH CHECK FOR CATCH BASIN NO. 5 Q100 TO OPENING (CFS) 9.09 TC AT OPENING 462.02 VS HGL 459.90 OK p.A4.21 C: \Documents and Settings \DRice \Local Settings \Temporary Internet Files \OLK73 \02226 SD_HGL_X.xls VELOCITY HEAD ELEV. IN PIPE, CB/15 458.50 Depth in Pipe at Q100(ft) 0.92 HV= V2 /2G= 0.48 SPECIFIC ENERGY 1.40 HGL AT U.S.END= 459.90 STREET CAPACITY: ARAGON WAY - D.A. #4 & #5 + PALATINE CIR. From the west to CB #1 & #3 TIME OF CONCENTRATION: INITIAL FLOW: Ti = k" (L ^3/h) ^.2 where: k = 0.39 L, length of initial flow = 157 Aragon Way h, elevation difference over initial flow = 0.8 Ti = 8.47 minutes STREET CAPACITY: SEGOVIA VIEW WAY Q= 1.486'A`RA2/3'S ^1/2 n where: A, X- sectional area of street = 8.05 sf Wetted perimeter = 32.33 R = 0.24899 S, slope = 0.0050 ft/ft n, Mannings coefficient = 0.017 Q = 19.69 cfs VELOCITY. in Street: V= Q/A where: Q, capacity, cfs = 19.69 A, area, sf = 8.05 V = 2.45 fps 060607 02226 STREET CAPACITY.As STREET FLOW: Ts= W Tc= Ti +Ts where: 11.90 min. L, length of flow = 503 V, street velocity = 2.45 Ts = 205.62 secs 3.43 min. DESIGN Q1oo: Q100 = where: C, runoff coefficient = I, rainfall intensity = A, drainage area = Q100 = p.A4.19 CVE 7/18/2006 C'I"A 0.8109 (From Plate D -5.7) 4.091 in /hr (10yr - From Plate D -4.1) (Palm Springs) 2.22 AC (Drainage Map) 7.36 cfs O.K. 9.72 (Palatine Court) 17.08 cfs O.K. Project: Ehline PN: 02226 BY: DLC STORM DRAIN DESIGN PREPARED BY COACHELLA VALLEY ENGINEERS ** *BASED ON 100 YEAR STORM * ** DATE: 07/20/06 * *REVISED ** STORM DRAIN LINE: "G" PIPE OUTLET DESIGN (MAXWELL PLUS) DIA.(IN) Q100(CFS) 18 0.93 SLOPE OF PIPE 0.1200 ft/ft HGL CALCULATIONS, PARTIAL DEPTH WATER DEPTH (Q100) IN PIPE 1.908 in VELOCITY @ 4100 9.28 fps TYPE OF PIPE HDPE DEPTH CHECK FOR CATCH BASIN NO. 2 Q100 TO OPENING (CFS) 0.22 TC AT OPENING 461.21 VS HGL 459.67 OK CONFL.Q100(CFS) 0.93 STORM DRAIN LINE: "F" PIPE DIA.(IN) Q100(CFS) 18 0.71 SLOPE OF PIPE 0.0050 ft/ft HGL CALCULATIONS, PARTIAL DEPTH WATER DEPTH (Q100) IN PIPE 3.614 in VELOCITY @ Q100 2.81 fps TYPE OF PIPE HDPE DEPTH CHECK FOR CATCH BASIN NO. 1 Q100 TO OPENING (CFS) 0.71 TC AT OPENING 461.21 VS HGL 458.92 OK C: \Documents and Settings \DRice \Local Settings \Temporary Internet Files \OLK73 \02226 SD_HGL_%a•22 CAPACITY: 36.38 cfs Q100(CFS): 0.93 cfs OK ELEV. IN PIPE, CB #2 458.17 Depth in Pipe at Q100(ft) 0.16 VELOCITY HEAD HV= V2 /2G= 1.34 SPECIFIC ENERGY 1.497 HGL AT U.S.END= 459.67 CAPACITY: 7.43 cfs Q100(CFS): 0.71 cfs OK ELEV. IN PIPE, CB #1 458.50 Depth in Pipe at Q100(ft) 0.30 VELOCITY HEAD HV= V2 /2G= 0.12 SPECIFIC ENERGY 0.42 HGL AT U.S.END= 458.92 Project: Ehline PN: 02226 BY: DLC STORM DRAIN DESIGN PREPARED BY COACHELLA VALLEY ENGINEERS ***BASED ON 100 YEAR STORM * ** DATE: 07/20/06 * *REVISED ** STORM DRAIN LINE: "PH.II -A" PIPE OUTLET DESIGN (MAXWELL PLUS) DIA.(IN) . Q100(CFS) 30 20.28 SLOPE OF PIPE 0.0210 ft/ft CAPACITY: Q100(CFS): HGL CALCULATIONS, PARTIAL DEPTH WATER DEPTH (Q100) IN PIPE 11.566 in VELOCITY @ Q100 11.62 -fps TYPE OF PIPE HDPE DEPTH CHECK FOR CATCH BASIN NO. 9 Q100 TO OPENING (CFS) 5.46 TC AT OPENING -463.95 VS HGL 463.31 OK CONFL.Q100(CFS) 20.28 STORM DRAIN LINE: "PH.11 -8 PIPE DIA.(IN) Q100(CFS) 24 14.82 SLOPE OF PIPE 0.0050 ft/ft HGL CALCULATIONS, PARTIAL DEPTH WATER DEPTH (Q100) IN PIPE 17.078 in VELOCITY @ Q100 6.20 fps TYPE OF PIPE HDPE IDEPTH CHECK FOR CATCH BASIN NO. 8 Q100 TO OPENING (CFS) 14.82 TC AT OPENING 463.98 VS HGL 462.27 OK p.A4.23 02226 SD_HGL_X.xls VELOCITY HEAD CAPACITY: Q100(CFS): VELOCITY HEAD 59.44 cfs 20.28 cfs OK ELEV. IN PIPE, CB #9 460.25 Depth in Pipe at Q100(ft) 0.96 HV= V2 /2G= 2.10 SPECIFIC ENERGY 3.06 HGL AT U.S.END= 463.31 15.99 cfs 14.82 cfs OK ELEV. IN PIPE, CB #9 460.25 Depth in Pipe at Q100(ft) 1.42 HV= V2 /2G= 0.60 SPECIFIC ENERGY 2.02 HGL AT U.S.END= 462.27 p.A4.24 C: \Documents and Settings \DRice \Local Settings \Temporary Internet Files \OLK73 \02226 SD_HGL_X.xls Project: Ehline PN: 02226 BY: DLC STORM DRAIN DESIGN PREPARED BY COACHELLA VALLEY ENGINEERS "'BASED ON 100 YEAR STORM "" DATE: 07/20/06 **REVISED** STORM DRAIN LINE: "A -off site" PIPE OUTLET DESIGN (MAXWELL PLUS) DIA.(IN) Q100(CFS) 18 2.11 1 SLOPE OF PIPE 0.0050 ft/ft CAPACITY: 7.43 cfs Q100(CFS): 2.11 cfs OK HGL CALCULATIONS, PARTIAL DEPTH ELEV. IN PIPE, CB #10 463.33 WATER DEPTH (Q100) IN PIPE 6.290 in Depth in Pipe at Q100(ft) 0.52 VELOCITY @ Q100 3.84 fps VELOCITY HEAD HV= V2 /2G= 0.23 TYPE OF PIPE HDPE SPECIFIC ENERGY 0.75 HGL AT U.S.END= 464.08 IDEPTH CHECK FOR CATCH BASIN NO. 10 Q100 TO OPENING (CFS) 2.11 TC AT OPENING 470.34 VS HGL 464.08 OK p.A4.24 C: \Documents and Settings \DRice \Local Settings \Temporary Internet Files \OLK73 \02226 SD_HGL_X.xls � � m m m m m m m m r m m m m m m m m Project: Ehline PN: 02226 BY: DLC STORM DRAIN DESIGN PREPARED BY COACHELLA VALLEY ENGINEERS DATE: 07/20/06 •'REVISED" STORM DRAIN LINE: "B -off" IPIPE OUTLET DESIGN (MAXWELL PLUS) DIA.(IN) Q100(CFS) 18 4.56 SLOPE OF PIPE 0.0050 ft/ft HGL CALCULATIONS, PARTIAL DEPTH WATER DEPTH (Q100) IN PIPE 9.701 in VELOCITY @ Q100 4.70 fps TYPE OF PIPE HDPE DEPTH CHECK FOR CATCH BASIN NO. 11 Q100 TO OPENING (CFS) 4.56 TC AT OPENING 462.65 VS HGL 456.46 OK p.A4.25 C: \Documents and Settings \DRice \Local Settings \Temporary Internet Files \OLK73 \02226 SD_HGL_X.xls CAPACITY: 7.43 cfs 0100(CFS): 4.56 cfs OK ELEV. IN PIPE, CB #11 455.31 Depth in Pipe at Q100(ft) 0.81 VELOCITY HEAD HV= V2 /2G= 0.34 SPECIFIC ENERGY 1.15 HGL AT U.S.END= 456.46 � M r M M M M M M M r M M M M M M r M Project: Ehline PN: 02226 LAND DEVELOPMENT OUTPUT - MANNINGS BY: DLC GIVEN INPUT DATA: "A" "B" "C" "D" "E" "F" "G" "II -A" "II -B" "Off -A" "Off -B" Shape Circular Circular Circular Circular Circular Circular Circular Circular Circular Circular Circular Solving for Depth of Depth of Depth of Depth of Depth of Depth of Depth of Depth of Depth of Depth of Depth of Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Diameter in. 27 27 27 30 30 18 18 30 24 18 18 Flowrate cfs 15.0400 18.0800 28.0700 15.0600 9.0900 0.7100 0.7100 20.2800 14.8200 2.1100 4.5600 Slope ft/ft 0.0050 0.0200 0.0311 0.0070 0.0050 0.0050 0.0050 0.0210 0.0050 0.0050 0.0050 Manning's n 0.0120 0.0120 0.0120 0.0120 0.0120 0.0120 0.0120 0.0120 0.0120 0.0120 0.0120 COMPUTE RESULTS: Depth in 15.61 11.56 10.85 13.29 11.05 3.61 1.91 11.57 17.08 6.29 9.70 Area sf 3.9761 3.9761 % 9.6211 4.0898 4.9087 1.7671 1.7671 4.9087 3.1416 1.7671 1.7671 Wetted Area sf 2.3811 1.6251 1.9686 2.0988 1.6408 0.2529 0.1002 1.7453 2.3912 0.5501 0.9712 Wetted Perimeter in 46.6387 38.5200 44.7756 43.6952 39.1272 16.7249 11.9381 40.1949 48.1861 20.8736 29.6784 Perimeter in 84.8230 84.8223 84.2300 94.2478 94.2478 56.5487 56.5487 94.2478 75.3982 56.5487 56.5487 Velocity fps 6.32 11.13 14.26 7.18 5.54 2.81 9.28 11.62 6.20 3.84 4.70 Hydraulic Radius in 7.35 6.12 6.33 6.92 6.04 2.18 1.21 6.25 7.15 0.29 0.39 Percent Full % 57.80% 42.81% 57.80% 44.30% 36.83% 20.07% 10.60% 38.5540 71.16 % 34.95% 53.90% Full flow Flowrate cfs 23.72 47.45 192.21 7.18 31.42 8.05 39.42 64.39 17.33 8.05 8.05 Full flow velocity fps 5.97 11.93 19.98 7.57 6.40 4.55 22.31 13.12 5.52 4.55 4.55 CRITICAL INFORMATION Critical Depth in 16.29 18.03 19.61 15.71 12.06 3.76 4.31 18.45 16.92 0.55 9.85 Critical Slope ft/ft 0.0044 0.0046 0.0034 0.0039 0.0036 0.0043 0.0042 0.0042 0.0049 0.0042 0.0048 Crititical Velocity fps 5.99 6.37 6.37 5.79 4.92 2.66 2.86 6:39 6.20 3.61 4.61 Critical Area sf 2.5103 2.8381 4.4059 2.6023 1.8465 0.2673 0.3253 3.1734 2.3901 0.5847 0.9897 Crititical perimeter in 47.9822 4.2899 5.2662 48.5443 41.2128 17.0777 18.4128 54.0265 47.5302 1.9478 2.4977 Critical hydraulic radius in 7.5337 0.6616 0.8366 7.7194 6.4519 2.2539 2.5440 8.4582 7.2410 0.3002 0.3962 Crititical top width in 27.0000 27.0000 3.4923 30.0000 29.4195 14.6285 15.3655 30.0000 24.0000 17.3640 18.0000 Specific energy ft 1.92 2.89 4.06 1.91 1.40 0.42 1.50 3.06 2.01 0.75 1.15 Minimum energy ft 2.0357 2.2542 2.4514 1.9638 1.5079 0.4695 0.5390 2.3064 2.1144 0.8225 1.2311 Froude number 1.0831 2.2959 3.1359 1.3762 1.1841 1.0786 4.9699 2.4190 1.0100 1.0904 1.0289 Flow condition supercritical supercritical supercritical supercritical supercritical p.A4.26 C: \Documents and Settings \DRice \Local Settings \Temporary Internet Files \OLK73 \02226 SD_HGL_X.xls Villereccio Avenue 58 HGL Partial Depth Design Procedure Coachella Valley Engineers Spread Table Program TM 31249 CVE 02226 Following is an explanation of the calculation procedure of the Excel Spread Table program used by CVE to quickly and accurately calculate the HGL, utilizing the specific energy, with the pipe flowing at partial depth. 1) The Pipe Dia. is taken from the Storm Drain plans. 2) The Qio(o) is the quantity of runoff going through the pipe based on the appropriate storm, either 10 year or 100 year. 3) The Slope of Pipe, is the slope of the pipe, in ft/ft. 4) The Capacity of the pipe is determined by the formula, Q = [0.463 D ... Syl /n. 5) The Water Depth in the pipe for the 100 year storm is obtained from LDD (AutoCad Land Desktop) calculations that are summarized on the last sheet. 6) The Velocity, is also obtained from LDD calculations as listed above. 7) The Type of Pipe is listed and is used to determine the proper Manning's number, n. 8) The Velocity Head, is determined by the formula, V2 /2g, where g =32.2 fps. 9) The Specific Energy of the pipe is determined by added the Velocity Head to the depth of flow in the pipe, during the 100 year storm. 10) The HGL at the Up Stream End, is determined by adding the Specific-Energy to the invert elevation of the pipe at the catch basin. 11) The Tc is the Top of Curb at the Catch Basin. The Tc is checked against the HGL at the upstream end. If the difference is greater than 05, then it is O.K. If it is a multiple catch basin /manhole system, the calculations are repeated as you go upstream. • FT-7. r OCoachella Valley engineers TO: City of La Quinta Steve Speer 78 -495 Calle Tampico La Quinta, CA.92263 -1504 760 - 777 -7043 760- 777 -7155 LETTER OF TRANSMITTAL - Date 9/12/03 :RE: ENCLOSED ARE THE FOLLOWING ITEMS SENT VIA: QUANTITY DESCRIPTION 1 CODV Infiltration /PercolationTestina Report Job No. 02226 THESE ARE TRANSMITTED as checked below: 0 For Approval 0 For Review and Comment [ For Your Use As Requested 0 For Signature 0 For Your Files Returned # Check Prints Other: REMARKS: If you have any questions or if enclosures are not as noted please call at your earliest convenience. cc: File No. of Pages Accepted. by: Signed: A"I Gail sse Project Coordinator 77 -899 WOLF ROAD, SUITE 102 PALM DESERT, CA 92211 TELEPHONE (760) 360 -4200 FAx (760) 360 -4204 Sladden Engineering 6782 Stanton Ave., Suite A, Buena Park, CA 90621 (714) 523 -0952 Fax (714) 523 -1369 39 -725 Garand Ln., Suite G, Palm Desert, CA 92211 (760) 772 -3893 Fax (760) 772 -3895 September 11, 2003 Project No. 544 -3272 5EP 12 2003 03 -09 -590 Madison 58 Partners, LLC '�c 77 -899 Wolf Road, Suite 101 Palm Desert, California 92211 Project: Tentative Tract 31249 Avenue 58 west of Madison Street La Quinta, California Subject: Infiltration /Percolation Testing for Stormwater Retention As requested, we have performed percolation /infiltration testing on the subject site in order to determine the infiltration potential of the surface soils. The percolation rates determined should be useful in assessing stormwater retention needs. It is our understanding that on -site stormwater retention will be required. It is proposed to collect the stormwater runoff within several shallow retention basins. Infiltration testing was performed within shallow test holes excavated in the areas of two of the proposed retention basins. Percolation testing was performed on June 24, 2003. Testing involved filling the test holes with water and recording the drop in the water surface with time. Measurements were recorded in 10 and 15 minute increments. Tests results are summarized below: Rate Test Hole No. (inches /hour) A 10.8 B 6:6=__- It should be noted that the infiltration rates determined are ultimate rates based upon field test results. An appropriate safety factor should be applied to account for subsoil inconsistencies and potential silting of the percolating soils. The safety factor should be determined with consideration to other factors in the stormwater retention system design (particularly stormwater volume estimates) and the safety factors associated with those design components. September 11, 2003 -2- Project No. 544 -3272 03 -09 -590 We appreciate the opportunity to provide service to you on this project. If you have questions regarding this letter or the data included, please contact the undersigned. Respectfully submitted, SLADDEN ENGINEERING A""' 12- Hogan R. Wright Project Engineer Letter /pc BSI ®H - i m M No. C 64276 x *\ Exp. 6/30/07 / */ CIvlL CA �TFOF UF�P� Copies: 4/ Madison 58 Partners, LLC s, ,. CRAPHIC SCALE TE TATO �V E TRA,`��• ?„ ll V \J ////�� 0� _ — .�'•,�� A'PECTION OF' HE NORTHEAST QUARTER OF THE NORTRwES {gU;�RTER,NEIIA NW l' /q OF *s+At7 MAP y� �yL SECTION 28, TOWNSHIP 6 SOUTH• RANGE 7 EAST OF THE SAN BERNARDINO MERIDIAN. %.'0 -I .'oCL. COUNTY OF RIVERSIDE. STATE OF CALIFORNIA ..-! CREST UF.V-ELOPMlMT C.OACrtELLA VALLEY ENGINEERS. INC. MAY, T:YJ] Ey� a I I ' •I wnt naa'r.. \i. `«a1i� _ N �I.n i � \ at n.ras - l_ :, m..., •. u. - . _.x.,76'- - �Y I:.IS'I.,. ,.. .. �.n .t � I f' B°tk..a5.o•� ..o•n Nwr COU:B� A ro .. ��•.n t !f�s�t•s \lle: �, -I •. �` s, .j K 'I r� 1:.4E s � �- TC:NSO l5. �.�� :'J:,:.s �':: t _ � .II �= {. -Si:r N:i ^�_L�• +� ".u_iK Y'r _� -: .,' -:�i:'r. r -Ili l.. : rj• <� � � i y�� s� • n$�•`, a I : r _ � .� .. t�' ��, j -e�. Ls r i.�u , �l ..r _ # C_:...._J t ` � + •! it ' I : , 'a -i 2 ar raie'. • � ` 'K :E 0 1'sw•LL�' I E"i {mss I yI• r 4 � I s. , - �am .S1; � :' „ti• . SFr Ir n 4 B ... __.�_�:. 10.8 i, 1 n. /hr. \� I iri 6.6 in. /hr. '.,`J�' 1�syl ,' ,• r ' •tifT`f i., .;;^ a \R - •:�'•:�:i •', Fu, �_ �ci o F n ,. �� i , ',. «� - -- - ' "L °t'. _.fir mss. _ .; ,o.•�.: � - L $ I .... I ` i >t . + - ' t •,.t— ^ 66 io. is q .. nw:'.a. � .. ... ,. I tii^ r1.ia«ns ;j s' _ �^ ,�(',.i �• '�'R.wv fd .K'a°•ens.__ -Rw.a .::: 4' .L La ... ... :��_: �.. r, aGaA::• s E I � '� � 4. --- -I , fl: - ::;� " . -. @�' � ... �:, s ,Waco «mss Is '• ; 3... � I . tL ,..MSU'vE ., c°rlurseo FG•' 4'•. nLa�s,., ❑: a CI P. aG 1. • i Et ,6 t 7B o' 75 ;zc ..c _ miza ' ` G 7a” 73 =I µ , y, 72 is: : 171 �a. %'•` x:,�__ -�, 1 �'.d. %•gell iAW%tp �.I�..� ,.. �.w� :... 'i ,w ar a..ul •.I; .. ,r _ •: L..,i �� -'+ •ow �- iwi�.= ilk / -': 'ic -! • '.t46ia�:c Si Lr ii In .xv> sr... �? _J 2• • :.1" �.,.;' 0.4 . -.p V �?.tn°' F _ ae. ,. .. : • ...e. ,r 4 •eo:: ,.' f e s,_ti'od: sr 27 K y 1�' . .. , /i M..n ." .I.1• In :w.l ��_.. 1,9_ �2.si — _'l.t�_ r North Approximate Stormwater Percolation Test Locations Reading No. Double Ring Stormwater Percolation Data Sheet Project: Tentative Tract 31249 / Madison St. / La Quinta, California Project No.: 544 -3272 Test Hole: A 1:27 Date Excavated: 6 -24 -03 Percolation Tested by: Tracy Yeager Soil Classification: SM Date Tested: 6 -24 -03 Time Time Inner Change Outer Change Outer Inner Outer of Interval Ring Inner Ring Outer Ring Ring Ring Readina (min.) (in.) (in.) (in ) (in ) Cnnversinn (in /hr 1 (in /hr 1 1:27 18.4 28.1 1 10 3.1 3.8 3.2 18.6 19.4 1:37 15.3 24.3 1:37 15.3 24.3 2 10 2.9 3.6 3.1 17.4 18.4 1:47 12.4 20.7 1:47 12.4 20.7 3 10 2.8 3.5 3.0 16.8 17.9 1:57 9.6 17.2 1:57 9.6 17.2 4 10 2.7 3.4 2.9 16.2 17.3 2:07 6.9 13.8 2:07 6.9 13.8 5 10 2.5 3.1 2.6 15.0 15.8 2:17 4.4 10.7 2:17 4.4 10.7 6 10 2.3 2.7 2.3 13.8 13.8 2:27 2.1 8.0 2:27 18.2 8.0 7 10 2.1 2.4 2.0 12.6 12.2 2:37 16.1 5.6 2:37 16.1 5.6 8 10 2.0 2.2 1.9 12.0 11.2 2:47 14.1 3.4 2:47 14.1 3.4 9 10 1.8 2.2 1.9 10.8 11.2 2:57 12.3 1.2 2:57 12.3 16.9 10 10 1.8 2.2 1.9 10.8 11.2 3:07 10.5 14.7 3:07 10.5 14.7 11 10 1.9 2.1 1.8 11.4 10.7 3:17 8.6 12.6 3:17 8.6 12.6 12 10 1.8 2.1 1.8 10.8 10.7 3:27 6.8 10.5 Double Ring Stormwater Percolation Data Sheet Project: Tentative Tract 31249 / Madison St. / La Quinta, California Project No.: 544 -3272 Test Hole: B Date Excavated: 6 -24 -03 Percolation Tested by: Tracy Yeager Soil Classification: SM Date Tested: 6 -24 -03 Reading Time Time Inner Change Outer Change Outer Inner Outer No. of Interval Ring Inner Ring Outer Ring Ring Ring Reading (min.) (in.) (in.) (in.) (in.) Conversion (in. /hr.) (in. /hr.) 9:34 18.2 28.3 1 15 4.0 5.0 4.3 16.0 17.0 9:49 14.2 23.3 9:49 14.2 23.3 2 15 2.9 3.7 3.1 11.6 12.6 10:04 11.3 19.6 10:04 11.3 19.6 3 15 2.4 3.0 2.6 9.6 10.2 10:19 8.9 16.6 10:19 8.9 16.6 4 15 2.1 2.7 2.3 8.4 9.2 10:34 6.8 13.9 10:34 6.8 13.9 5 15 1.8 2.4 2.0 7.2 8.2 10:49 5.0 11.5 10:49 5.0 11.5 6 15 1.8 2.2 1.9 7.2 7.5 11:04 3.2 9.3 11:04 18.0 9.3 7 15 1.8 2.1 1.8 7.2 7.1 11:19 16.2 7.2 11:19 16.2 7.2 8 15 1.8 2.2 1.9 7.2 7.5 11:34 14.4 5.0 11:34 14.4 5.0 9 15 1.7 2.1 - 1.8 - 6.8 7.1 11:49 12.7 2.9 11:49 12.7 11.6 10 15 1.6 2.1 1.8 6.4 7.1 12:04 11.1 9.5 12:04 11.1 9.5 11 15 1.7 2.2 1.9 6.8 7.5 12:19 9.4 7.3 12:19 9.4 7.3 12 15 1.8 2.2 1.9 7.2 7.5 12:34 7.6 5.1 �l CITY OF LA QUINTA PUBLIC WORKS/ ENGINEERING % 78 -495 CALLE TAMPICO � LA QUINTA, CA 92253 FACSIMILE TRANSMITTAL SHEET TO Wm b� `� V!� V G &FROM: J�g�jl,ipA . COM Y: D ATE: ` q Ll 3 16 FAX NUMBER: TOTAL NO. OF PAGES INCLUDING COVER PHONE NUMBER: SENDER'S PHONE NUMBER: 760-777 -7075 RE: SENDER'S FAX NUMBER: 760 -777 -7155 ❑ URGENT ❑ FOR REVIEW 0:�ER YOUR REQUEST O PLEASE REPLY ❑ PLEASE RECYCLE NOTES /COMMENTS: yo `ti'' d�-- MAILING ADDRESS: P.O. BOX 1504 LA QUINTA, CALIFORNIA 92253 o� Coachella Valley TO: City of La Quinta Wally Nesbit PO Box 1504 La Quinta, CA.92253 -1504 760 -777 -7069 760 - 777 -1233 E Fp 9 X003 ENCLOSED ARE THE FOLLOWING ITEMS SENT VIA: LETTER OF TRANSMITTAL Date Job No. 9/08/03 02226 RE: Soils Report 7X+ < --T' 3 iz 07 QUANTITY DESCRIPTION ` 1 Soils Report for Madison & 58th wi fQ.k THESE ARE TRANSMITTED as checked below: 0 For Approval 0 For Review and Comment xx For Your Use Ox As Requested 0 For Signature For Your Files 0 Returned # Check Prints 0 Other: REMARKS: If you have any questions or if enclosures are not as noted please call at your earliest convenience. cc: File No. of Pages Accepted by: C0 J Signed: ��' a G it asse ecf Coordinator 77 -899 WOLF ROAD, SUITE 102 PALM DESERT, CA 92211 TELEPHONE (760) 360 -4200 FAX (760) 360 -4204 I Received: 9/ 9/03 6:02PM; 760 772 3895 -> Coachella Valley Engineers; Paige 1 'jtl Sep 09 03 05:59p sladden palm desert 760 772 3895 P.1 SLADDEN ENGINEERING (760) 772 -3893 - (760) 772 -3895 FAX FACSIMILE TRANSMITTAL SHEET TO: FROM: COMPANY: DATE: G v FAX NUMBER: TOTAL NO. OF PAGES INCLUDING COVER: .3ko - yzo!j z PHONE NUMBER: SENDER'S REFGRSNCFi NUMBER: RE: YOUR REFERENCE NUMBER: ❑ URGENT ❑ FOR REVIEW ❑ PLEASL COMMENT' ❑ PLEASE RLPLY ❑ PLFASI- RECYCLE. N OlT 5 /COMh1r..N'I'S: Pere OI C4" 4- -SAW— wilt'7 R = 66,c, /tip, 39 -725 GARAND LANE, SUITE G PALM DESERT, CALIFORNIA 92211 Received: 9/ 9/03 6:02PM; 760 772 3895 -> Coachella Valley Engineers; Page 2 Sep 09 03 05:59p sladden palm desert 760 772 3895 p.2 M. \y /y {Irr /,/any �I' , M� \y/ . •..3� ( g .._ Lw•Vlllr. 34ALr ��.V APECTION Of iOENSHIP 6 SO TH. QUARTER RANGE 7 THE EAST OF IM SAN ER.4Ek !.OmEWI'//I. SECTION 28. TOWNSHIP p SCUM. RAN(TE 7 EAST Of fNE SAN BERNwkUY,O MERICIAN. COUNTY Of "ERSIOE. STATE Of CALIFORNIA Iff.YlLc""') COACratw VARD ENGWEM.01. MAI. M3 y n ' 1 u„40•'0 ... Krli� � I J - .i1. "y ;!r •rrira° Knu nw; J 1 ! vaw° + rtiri I kar ri uai ! M !ftji 1111 : p�- J C .w. w.,.5,4 .,..,, .Y�?48;r3ti•'_.•. 4' -- -f �,ii ,FLL _ ." 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F .�` -�'�:,.:. ,..f°ia�cr�e,� "',; - ev,.I ..:r _ — _,aa__•u'� —, � � II,E! 0 0.: I' {iy' � _ •.F. �- _ _.TTY_ -- '- - -r ..- - ..,;_.. _ -. � "ti' - 1,\°�_ _ r � ' '' . -:lg., 'us.:fl:i-' .[t . � '.e', !Yr f I~ �!4 c,�5�, wcu, 7. .S ES a .,. v.'•'t' ' '! .•�': •,u!_:'�� .: r_'�.74P+_'� _�t�7 .___ar,�,�_��,r ,� y�- --- -I -.. ..�.. vim_ -o_ : - :_. ._�'. .... _.J;: , �'� � :r 1......,,r a �: '" .. .i,>• i «'u 7- i 'ree_ _ - t_ L_ _ i //'� Percolation Test Location Map Proposed 33 -acre Residential Development Tentative Tract 31249 Avenue 58 west of Madison Street North Approximate St:ormwater La Quinta, California Percolation Test Locations Sladden Engineering Project Number: 544 -3272 1 Date: 8 -20 -03 SLRDDEN ENGINEERING Soil Engineers 6782 Stanton Ave., Suite A, Buena Park, CA 90621 • (562) 864 -4121 • (714) 523 -0952 39 -725 Garand Ln., -Suite G, Palm Desert, CA 92211 • (760) 772 -3893 l I �` � ``. J i 1 -:a GEOTECHNICAL INVESTIGATION TENTATIVE TRACT NO. 31249 AVENUE 58 WEST OF MADISON STREET LA QUINTA, CALIFORNIA - Prepared By- Sladden Engineering 39 -725 Garand Lane, Suite G Palm Desert, California 92211 (760) 772 -3893 ;® Y I' Y S adden Engineering 6782 Stanton Ave., Suite A, Buena Park, CA 90621 (714) 523 -0952 Fax (714) 523 -1369 39 -725 Garand Ln., Suite G, Palm Desert, CA 92211 (760) 772 -3893 Fax (760) 772 -3895 �� as August 20, 2003 Project No. 544 -3272 03-08-544 Madison 58 Partners, LLC 77 -899 Wolf Road, Suite 101 Palm Desert, California 92211 Project: Tentative Tract 31249 Avenue 58 West of Madison Street La Quinta, California Subject: GeotechnicalInvestigation Presented herewith is the report of our Geotechnical Investigation conducted at the site of the proposed residential development located on the south side of Avenue 58 west of Madison Street in the City of La Quinta, California. The investigation was performed in order to provide recommendations for site preparation and to assist in foundation design for the proposed residential structures and the related site improvements. This report presents the results of our field investigation and laboratory testing along with ' conclusions and recommendations for foundation design and site preparation. This report completes our original scope of services as outlined in our proposal dated June 16, 2003. We appreciate the opportunity to provide service to you on this project. If you have any questions regarding this report, please contact the undersigned Respectfully submitted, SLADDEN ENGINEERING Brett L. Anderson Principal Engineer SER/pc �PpFESSIO ANQFRs0 �c2c m Z m m No. C 45389 * Exp.9130106 S'T C I V 1L P�\P \�TFOF CAL \FO / ICopies: 6/Madison 58 Partners, LLC t Ti^r. GEOTECHNICAL INVESTIGATION TENTATIVE TRACT 31249 AVENUE 58 WEST OF MADISON STREET LA QUINTA, CALIFORNIA August 22, 2003 TABLE OF CONTENTS INTRODUCTION........................................................................................ ............................... 1 SCOPEOF WORK ...................................................................................... ............................... 1 PROJECT DESCRIPTION ......................................................................... ............................... 1 i SUBSURFACE CONDITIONS .................................................................. ............................... 2 CONCLUSIONS AND RECOMMENDATIONS ....................................... ............................... 2 FoundationDesign ............................................................................... ............................... 3 i Settlements ........................................................................................... ............................... 3 LateralDesign ...................................................................................... ............................... 3 RetainingWalls .................................................................................... ............................... 4 ExpansiveSoils ..................................................................................... ............................... 4 i Concrete Slabs-on- Grade ...................................................................... ............................... 4 SolubleSulfates .................................................................................... ............................... 4 Tentative Pavement Design ................................................................. ............................... 4 Shrinkage and Subsidence ................................................................... ............................... 5 GeneralSite Grading ............................................................................ ............................... 5 1. Clearing and Grubbing .............................................................. ............................... 5 i 2. Preparation of Building and Foundation Areas ....................... ............................... 4 3. Preparation of Surfaces to Receive Compacted Fill ................. ............................... 5 4. Placement of Compacted Fill ..................................................... ............................... 5 5. Preparation of Slab and Paving Areas ...................................... ............................... 6 6. Testing and Inspection ............................................................... ............................... 6 GENERAL................................................................................................... ............................... 6 iAPPENDIX A - ' APPENDIX B - ' APPENDIX C - 1 1 Site Plan and Boring Logs Field Exploration Laboratory Testing Laboratory Test Results 1997 UBC Seismic Design Criteria r S .a August 20, 2003 ,s -1- INTRODUCTION i � • y .3 N. , - - Y�,} -s Project No. 54473272 03-08-544 This report presents the results of our Geotechnical Investigation performed in order to provide recommendations for site preparation and to assist in the design and construction of the foundations for the proposed residential structures. The project site is located on the south side of Avenue 58 west of Madison Street in the City of La Quinta, California. The preliminary plans indicate that the proposed project consists of an approximately 33 acre residential subdivision. The associated site improvements are expected to include paved roadways, concrete driveways, walkways and patios, swimming pools, landscape areas and various underground utilities. SCOPE OF WORK The purpose of our investigation was to determine certain engineering characteristics of the near surface soils on the site in order to develop recommendations for foundation design and site preparation. Our investigation included field exploration, laboratory testing, engineering analysis and the preparation of this report. Evaluation of environmental issues or hazardous wastes was not within the scope of services provided. Our investigation was performed in accordance with contemporary geotechnical engineering principles and practice. We make no other warranty, either express or implied. PROJECT DESCRIPTION The project site is located on the south side of Avenue 58 west of Madison Street in the La Quinta area of Riverside County, California. The preliminary plans indicate that the project will consist of an approximately 33 acre residential subdivision. . It is our understanding that the proposed residential structures will be of relatively lightweight wood-frame construction and will be supported by conventional shallow spread footings and concrete slabs on grade. The associated site improvements will include paved roadways, concrete walkways, patios and driveways, swimming pools, landscape areas and various underground utilities. The project site is mostly vacant and appears to have been previously used for agricultural production. The entire site is fallow but evidence of previous agricultural production and a nursery facility. Scattered concrete foundations and small structures exist along the north side of the site. There is existing water well located at the north central portion of the site. The adjacent property to the south, east and west of the site remains vacant. Avenue 58 forms the northern site boundary. There are existing overhead and underground utilities along Avenue 58 and possibly transecting the subject site. Based upon our previous experience with lightweight wood-frame structures, we expect that isolated column loads will be less than 30 kips and wall loading will be less than to 3.0 kips per linear foot. Grading is expected to include minor cuts and fills to match the nearby elevations and to construct slightly elevated building pads to accommodate site drainage. This does not include removal and recompaction of the foundation bearing soils within the building areas. If the anticipated foundation loading or site grading varies substantially from that assumed, the recommendations included in this report should be reevaluated. Sladden Engineering August 20, `2003 -2- Project No. 544-3272 03-08-544 SUBSURFACE CONDITIONS The hedfsurface soils observed within our borings consist primarily of fine-grained silty sands with scattered generally thin sandy silt, clayey silt, and silty clay layers. Silty fine-grained sands were the most prominent soil type encountered but several prominent sandy silt and silty clay layers were also observed within several of our borings. In general, the site soils appeared somewhat loose near the surface but laboratory test results and sampler penetration resistance (as measured by field blowcounts) suggest that the site soils become somewhat firmer with depth. The majority of the site soils were found to be dry throughout the depth of our borings but some of the silt deeper layers were wet. Laboratory classification testing indicates that the near surface soils consist primarily of a somewhat inconsistent mixture of silty fine-grained sands. Expansion test results indicate that the majority of the near surface soils are non - expansive and fall within the "very low" expansion category in accordance with the Uniform Building Code classification system. Consolidation testing indicates that some of the near surface soils are potentially compressible and may be susceptible to detrimental hydroconsolidation and /or compression related settlements. Groundwater was not encountered within our borings that extended to a maximum depth of approximately 51 feet below the existing ground surface. Groundwater should not be a factor in foundation design or construction. CONCLUSIONS AND RECOMMENDATIONS Based upon our field and laboratory investigation, it is our opinion that the proposed residential development is feasible from a soil mechanic's standpoint provided that the recommendations included in this report are considered in building foundation design and site preparation. Due to the somewhat loose and compressible conditions of the near surface soils, remedial grading including overexcavation and recompaction is recommended for the proposed building areas. We recommend that remedial grading within the proposed building areas include overexcavation and recompaction of the loose surface soils as well as the primary foundation bearing soils. Specific recommendations for site preparation are presented in the Site Grading section of this report. Groundwater was not encountered within our borings that extended to a depth of approximately 51 ' feet below the existing ground surface. Due to the depth to groundwater, specific liquefaction analyses were not performed. Based upon the depth to groundwater, the potential for liquefaction and the related surficial affects of liquefaction impacting the site are considered negligible. The site is located within an active seismic area of Southern California within approximately 13.5 kilometers of the San Andreas Fault system. Strong ground motion resulting from earthquake activity along the nearby San Andreas or San Jacinto fault systems is likely to impact the site during ' the anticipated lifetime of the structures. Structures should be designed by professionals familiar with the geologic and seismic setting of the site. As a minimum, structure design should conform to Uniform Building Code (UBC) requirements for Seismic Zone 4. Pertinent seismic design criteria as outlined in the 1997 UBC, is summarized in Appendix C of this report. Caving did occur to varying degrees within each of our exploratory borings and the surface soils may be susceptible to caving within deeper. excavations.' All excavations should be constructed in ' accordance with the normal CalOSHA excavation criteria. On the basis of our observations of the materials encountered, we anticipate that the subsoils will conform to those described by CalOSHA as Type C. Soil conditions should be verified in the field by a "Competent person" employed by the Contractor. Sladden Engineering August 20, 2003 -3- Project No. 544-3272 03-08-544 The majority of the surface soils encountered during our investigation were found to be non- evansive. Laboratory testing indicated an Expansion Index of 0 for the silty sands that dominate the site, which corresponds with the "very low" expansion category in accordance with UBC Standard 18-2. If imported soils are to be used during grading, they should have an Expansion Index of less than 20. The following recommendations present more detailed design criteria, which have been developed on the basis of our field and laboratory investigation. Foundation Design: The results of our investigation indicate that either conventional shallow continuous footings or isolated pad footings that are supported upon properly compacted soils may be expected to provide satisfactory support for the proposed structures. Overexcavation and recompaction should be performed as described in the Site Grading Section of this report. Footings should extend at least 12 inches beneath lowest adjacent grade. Isolated square or rectangular footings at least 2 feet square may be designed using an allowable bearing value of 1800 pounds per square foot. Continuous footings at least 12 inches wide may be designed using an allowable bearing pressure of 1500 pounds per square foot. Allowable increases of 200 psf for each additional 1 foot of width and 200 psf for each additional 6 inches of depth may be utilized if desired. The maximum allowable bearing pressure should be 2500 psf. The allowable bearing pressures are for dead and frequently applied live loads and may be increased by 1/3 to resist wind, seismic or other transient loading. Care should be taken to see that bearing soils are not allowed to become saturated from the ponding of rainwater or irrigation. Drainage from the building areas should be rapid and complete. The recommendations made in the preceding paragraphs are based on the assumption that all footings will be supported upon properly compacted soil. All grading shall be performed under the testing and inspection of the Soils Engineer or his representative. Prior to the placement of concrete, we recommend that the footing excavations be inspected in order to verify that they extend into compacted soil and are free of loose and disturbed materials. Settlements: Settlements may result from the anticipated foundation loads. These estimated ultimate settlements are calculated to be a maximum of 1 inch when using the recommended bearing values. As a practical matter, differential settlements between footings can be assumed as one-half of the total settlement. Lateral Design: Resistance to lateral loads can be provided by a combination of friction acting at the base of the slabs or foundations and passive earth pressure along the sides of the foundations. A coefficient of friction of 0.40 between soil and concrete may be used with dead load forces only. A passive earth pressure of 275 pounds per square foot, per foot of depth, may be used for the sides of footings, which are poured against properly compacted native soils. Passive earth pressure should be ignored within the upper 1 foot except where confined (such as beneath a floor slab). When. used in combination, either the passive resistance or the coefficient of friction should be reduced by one-third. Sladden Engineering -f August 20, 2003 -4 Project No. 544-3272 03= 08-544 Retaining Walls: Retaining walls may be required to accomplish the proposed construction. Cantilever retaining walls may be designed using "active" pressures. Active pressures may be estimated using an equivalent fluid weight of 35 pcf for native backfill soils with level free-draining backfill conditions. For walls that are restrained, "at rest" pressures should be utilized in design. At rest pressures may be estimated using an equivalent fluid weight of 55 pcf for native backfill soils with level free-draining backfill conditions. Expansive Soils: Due to the prominence of non-expansive soils on the site, special expansive soil design criteria should not be necessary for the design of foundations and concrete slabs - on- grade. Because the mixing and blending associated with the recommended remedial grading may change expansion potential, final design criteria should be established by the Structural Engineer based upon post grading expansion test results. Concrete Slabs-on - Grade All surfaces to receive concrete slabs-on-grade should be underlain by recompacted soils as described in the Site Grading Section of this report. Where slabs are to receive moisture sensitive floor coverings or where dampness of the floor slab is not desired, we recommend the use of an appropriate vapor barrier. Vapor barriers should be protected by sand in order to reduce the possibility of puncture and to aid in obtaining uniform concrete curing. Reinforcement of slabs- on-grade in order to resist expansive soil pressures may not be required. However, reinforcement will have a beneficial effect in containing cracking due to concrete shrinkage. Temperature and shrinkage related cracking should be anticipated in all concrete slabs-on-grade. Slab reinforcement and the spacing of control joints should be determined by the Structural Engineer. Soluble Sulfates: The soluble sulfate concentration of a bulk sample of the near surface soils determined to be approximately 1560 parts per million (ppm) which is considered potentially corrosive with respect to concrete. The use of Type 5 cement or sulfate resistant concrete mix designs may be necessary. Soluble sulfate content of the surface soils should be reevaluated after rough grading. Tentative Pavement Design: All paving should be underlain by a minimum compacted fill thickness of 12 inches (excluding aggregate base). This may be performed as described in the Site Grading Section of this report. The following preliminary pavement sections are based upon a design R-Value of 50. Onsite Roadways (Traffic Index = 6.0) Use 3.0 inches of asphalt on 4.0 inches of Class 2 base material Aggregate base should conform to the requirements for Class 2 Aggregate base in Section 26 of CalTrans Standard Specifications, January 1992. Asphaltic concrete should conform to Section 39 of the CalTrans Standard Specifications. The recommended sections should be provided with a uniformly compacted subgrade and precise control of thickness and elevations during placement. Sladden Engineering August 20, 2003 5 Project No. 544-3272 03-08=544 Shrinkage and Subsidence: Volumetric shrinkage of the material that is excavated and replaced as controlled compacted fill should be anticipated. We estimate that this shrinkage -� should vary from 20 to 25 percent. Subsidence of the surfaces that are scarified and compacted should be between 0.2 and 0.3 tenths of a foot. This will vary depending upon the type of equipment used, the moisture content of the soil at the time of grading and the actual degree of compaction attained. These values for shrinkage and subsidence are exclusive of losses which will occur due to the stripping of the organic material from the site, the removal of deleterious materials and the removal of debris, trees and other subsurface obstructions. General Site Grading: All grading should be performed in accordance with the grading ordinance of the City of La Quinta, California. The following recommendations have been developed on the basis of our field and laboratory testing: 1. Clearing and Grubbing: Proper clearing of any existing vegetation, root systems, debris, foundations, slabs, pavements and underground utilities will be very important. All surfaces to receive compacted fill should be cleared of roots, vegetation, debris, and other unsuitable materials that should be removed from the site. Soils that are disturbed due to site clearing should be replaced as controlled compacted fill under the direction of the Soils Engineer. 2. Preparation of Building and Foundation Areas: Building areas should be overexcavated to a depth of at least 3 feet below existing grade or 2 feet below the bottom of the footings, whichever is deeper. The exposed surface should be scarified, moisture conditioned and compacted so that a minimum of 90 percent relative compaction is attained. Once deleterious materials are removed, the native material may be placed as controlled compacted fill. Overexcavation should be observed by a representative of Sladden Engineering and compaction should be verified by testing. 3. Preparation of Surfaces to Receive Compacted Fill= Other areas to receive compacted fill should be brought to near optimum moisture content and compacted to a minimum of 90 percent relative compaction. 4. Placement of Compacted Fill: Fill materials consisting of on-site soils or approved imported granular soils, should be spread in thin lifts, and compacted at near optimum moisture content to a minimum of 90 percent relative compaction. Imported material shall have an Expansion Index not exceeding 20. The contractor shall notify the Soils Engineer at least 48 hours in advance of importing soils in order to provide sufficient time for the proper evaluation of proposed import materials. The contractor shall be responsible for delivering material to the site, which complies with the project specifications. Approval by the Soils Engineer will be based upon material delivered to the site and not the preliminary evaluation of import sources. Our observations of the material encountered during our investigation indicate that compaction will be most readily obtained by means of heavy rubber-wheeled equipment and/or vibratory compactors. Sladden Engineering August 20, 2003. . I 5. Preparation of Slab and Paving Areas: All surfaces to receive asphalt concrete paving or concrete slabs-on-grade, should be underlain by a minimum compacted fill thickness of 12 inches. This may be accomplished by a combination of scarification and recompaction of the surface soils and placement of the fill material as controlled ' compacted fill. Compaction of the slab and pavement areas should be to a minimum of 90 percent relative compaction. 6. Testing and Inspection= During grading tests and observations should be performed by the Soils Engineer or his representative in order to verify that the grading is being performed in accordance with the project specifications. Field density testing shall be performed in accordance with acceptable ASTM test methods. The minimum acceptable degree of compaction should be 90 percent of the maximum dry density as obtained by the ASTM D1557-91 test method. Where testing indicates insufficient density, additional compactive effort shall be applied until retesting indicates satisfactory compaction. GENERAL The findings and recommendations presented in this report are based upon an interpolation of the soil conditions between the exploratory boring locations and extrapolation of these conditions throughout the proposed building area. Should conditions encountered during grading appear different than those indicated in this report, this office should be notified. This report is considered to be applicable for use by Madison 58 Partners, LLC for the specific site and project described herein. The use of this report by other parties or for other projects is not authorized. The recommendations of this report are contingent upon monitoring of the grading operation by a representative of Sladden Engineering. All recommendations are considered to be tentative pending our review of the grading operation and additional testing, if indicated. If others are employed to perform any soil testing, this office should be notified prior to such testing in order to coordinate any required site visits by our representative and to assure indemnification of Sladden Engineering. We recommend that a pre-job conference be held on the site prior to the initiation of site grading. The purpose of this meeting will be to assure a complete understanding of the recommendations presented in this report as they apply to the actual grading performed. Sladden Engineering -6- I 5. Preparation of Slab and Paving Areas: All surfaces to receive asphalt concrete paving or concrete slabs-on-grade, should be underlain by a minimum compacted fill thickness of 12 inches. This may be accomplished by a combination of scarification and recompaction of the surface soils and placement of the fill material as controlled ' compacted fill. Compaction of the slab and pavement areas should be to a minimum of 90 percent relative compaction. 6. Testing and Inspection= During grading tests and observations should be performed by the Soils Engineer or his representative in order to verify that the grading is being performed in accordance with the project specifications. Field density testing shall be performed in accordance with acceptable ASTM test methods. The minimum acceptable degree of compaction should be 90 percent of the maximum dry density as obtained by the ASTM D1557-91 test method. Where testing indicates insufficient density, additional compactive effort shall be applied until retesting indicates satisfactory compaction. GENERAL The findings and recommendations presented in this report are based upon an interpolation of the soil conditions between the exploratory boring locations and extrapolation of these conditions throughout the proposed building area. Should conditions encountered during grading appear different than those indicated in this report, this office should be notified. This report is considered to be applicable for use by Madison 58 Partners, LLC for the specific site and project described herein. The use of this report by other parties or for other projects is not authorized. The recommendations of this report are contingent upon monitoring of the grading operation by a representative of Sladden Engineering. All recommendations are considered to be tentative pending our review of the grading operation and additional testing, if indicated. If others are employed to perform any soil testing, this office should be notified prior to such testing in order to coordinate any required site visits by our representative and to assure indemnification of Sladden Engineering. We recommend that a pre-job conference be held on the site prior to the initiation of site grading. The purpose of this meeting will be to assure a complete understanding of the recommendations presented in this report as they apply to the actual grading performed. Sladden Engineering -a APPENDIX A Site Plan Boring Logs -sa APPENDIX A FIELD EXPLORATION For our field investigation, 8 exploratory borings were excavated on June 20, 2003, using a truck mounted hollow stem auger rig (Mobile B61) in the approximate locations indicated on the site plan included in this appendix. Continuous logs of the materials encountered were prepared on the site by a representative of Sladden Engineering. Boring logs are included in this appendix. Representative undisturbed samples were obtained within our borings by driving a thin-walled steel penetration sampler (California split spoon sampler) or a Standard Penetration Test (SPT) sampler with a 140 pound hammer dropping approximately 30 inches (ASTM D1586). The number of blows required to drive the samplers 18 inches was recorded in 6 inch increments and blowcounts are indicated on the boring logs. The California samplers are 3.0 inches in diameter, carrying brass sample rings having inner diameters of 2.5 inches. The standard penetration samplers are 2.0 inches in diameter with an inner diameter of 1.5 inches. Undisturbed samples were removed from the sampler and placed in moisture sealed containers in order to preserve the natural soil moisture content. Bulk samples were obtained from the excavation spoils and samples were then transported to our laboratory for further observations and testing. iZ MOM— V. M 40 3 -D TapnQuads Copyright 0 1999 D01.OrMC Yarmouth, lNIE 114096 Source Data: USCS 1000 ft Scale: I :25.000 Detail: 13 -0 Datum WCS84 Vicinity Map Proposed 33 -acre Residential Development Tentative Tract 31249 Avenue 58 west of Madison Street North La uinta, California Sladden Engineering Project Number: 544 -3272 Date: 8 -20 -03 A.6 I ' � - NJ7 3/8 - vENUE AVEFvu SITE •. � 2g .' G %eel %`i . �`•� •`�`�„ .r 7 ' I ;"Pit 1 '•�t� 5(': 'Cahull�a Co• n;4 Parll: t • .I �:' i. ^J-:. �'-' ill � _ i4lo ` i II_ f N37�36:5' N33�38' � iZ MOM— V. M 40 3 -D TapnQuads Copyright 0 1999 D01.OrMC Yarmouth, lNIE 114096 Source Data: USCS 1000 ft Scale: I :25.000 Detail: 13 -0 Datum WCS84 Vicinity Map Proposed 33 -acre Residential Development Tentative Tract 31249 Avenue 58 west of Madison Street North La uinta, California Sladden Engineering Project Number: 544 -3272 Date: 8 -20 -03 A.6 I ' � - NJ7 3/8 - vENUE AVEFvu SITE •. � 2g .' G %eel %`i . �`•� •`�`�„ .r 7 ' I ;"Pit CRAPIIIC SCALE WP.• U VO — A PORTION OF iME NORTHFAS1 QUARTER OF THE NORTHWE$T�&A ER,uEIp NW I /J) OF _ __ —� : - "ACT V. v�.>aK SECTION 48. TOWNSHIP 6 SOUTH, RANGE 7 EAii OF THE SAN BERNARpwO r+tERICTAN. -'" " •�' r `-=� COUNIY OF R:VERSIOE. STATE OF CALIFORNIA ..:. +_ C.RF.L[CF.'tfIOPOV/") COACNCIt. LLD ENGINEERS. INC. M3 UE ��4�;;i?� .. ��y,�- .t :na n:na ti.°rr J,�i�T�7, �� ,�.�S�i1 � � nwa ' .eu r�i.w�i II .suu: )• I' �i" nr..� `��no..t .�a�� .. n l . , •. `�� "•,�; / L'Ei',: i ' fh� "` .� }'I '•i� -- - - rI• -•ate 's � `t�... .::T,..�•y,u,_ IJ5 'I• _.__.... _ i ' �\ ' i I "9 e i t • . ,7 5)' Tj- - t _ �• ~ ; r . �'. JyI,T Yt'; :_..�. _: i .. .._ ... _ CCC _�• iii yi t I 45 . , ' , � - "" "117111 •Y North 41- Approximate Boring Locations Ili�t lti 4 :j, --•Sg� � :.;:ter ,,:�' - I .F �frl __IL ._. �, - ... ;. - r- 'aV: Proposed 33 Acre ':Residental'Developnierit Tentative Tract 31249 / Avenue 58 west of Madison Street / La Quinta, California Date: 6 -20 -03 orin2 No. 2 Job No.: 544 -3272 i v o DESCRIPTION REMARKS E � A `. rn c U _o� c4 rn _° o o o U o Silty Sand: Brown, SM - very silty, fine grained 5 10/18/26 " " 106 4 - -- 33% passing #200 10 _ 10/14/18 Sand: Brown, SP /SM 100 2 - -- 7% passing #200 slightly silty, fine grained 15 _ 10/18/22 104 2 - -- 10% passing 9200 - Total Depth = 16.5 - ® Recovered Sample No Bedrock - No Groundwater 20 25 30 35 40 45 50 - Note: The stratification lines 55 represent the approximate boundaries between the soil ty pes; the transitions may be gradual. 7' - � 1, Propose ' d-33 "Acre Residential Development - �`a Tentative Tract 31249 /Avenue 58 west -of 1Vladison Street / La Quinta, California . Date: 6 -20 -03 Borin No. 3 Job No.: 544 -3272 o � DESCRIPTION T: � REMARKS ww E A 'p ri U oA rn 0 - Clayey Silt: Brown ML s 10/12/16 93 7 - -- 86% passing #200 10 - 18/24/28 Sand: Brown, SP /SM 110 1 - -- 8% passing #200 - slightly silty, fine grained is - - 12/18/28 ., 100 3 - -- 9% passing #200 zo _ 8/12/16 ' 97 2 - -- 7% passing #200 - Total Depth= 21.5 - � Recovered Sample No Bedrock - No Groundwater 2s 30 3s 40 45 50 - _ pes; Note: The stratification lines ss the transitions may be gradual. represent the approximate boundaries between the soil ty 7' - pes; the transitions may be gradual. 7' - u it Proposed.33 Ac' M4 sidentiahDevelopiiient Tentative. Tract 31249 PA venue 58 west of Madison Street / La Quinta, California - - Date: 6 -20 -03 Borin No. 4 Job No.: 544 -3272 'A + •��* _ :' LL -'� - � a �Ga. �T I, - o o. REMARKS:* a p •�, � LYi y p A `. � o U o� •o u °• o o o U 0 u it Proposed.33 Ac' M4 sidentiahDevelopiiient Tentative. Tract 31249 PA venue 58 west of Madison Street / La Quinta, California - - Date: 6 -20 -03 Borin No. 4 Job No.: 544 -3272 � � a DESCRIPTION -°' A o o. REMARKS:* a p •�, � LYi y p A `. � o U o� •o u °• o o o U 0 Silty Sand: Brown, SM fine grained 5 Silty Sand: Brown, SM - 3/5/8 very silty, fine grained --- 9 - 41% pass n #200 P g - Sandy Silt: Brown, clayey ML 10 Sand: Brown, slightly silty SP /SM - 8 /10/12 fine grained 8 __- 44% passing #200 - with silt layer 2" thick �5 6/12/16 Silty Sand: Brown, SM - -- 3 - -- 18% passing #200 fine grained 20 Clayey Silt: Brown with thin ML _ 8/11/17 interbedded sil sand layers 17 __- 70% passing #200 P g Total Depth = 21.5' - - Recovered Sample No Bedrock - No Groundwater 25 30 35 40 45 50 _ Note: The stratification lines 55 represent the approximate boundaries between the soil ty pes; the transitions may be gradual. r -- R�` . `Prop soed 33 Acr6:Res fd I I Development Tentative TiFact 312497"Ay"eniue 58 west of Madison Street La Quinta,taii,fornia Date: 6-20-03 Borine No. 6 Job No.: 544-3272 is Z #. T `Prop soed 33 Acr6:Res fd I I Development Tentative TiFact 312497"Ay"eniue 58 west of Madison Street La Quinta,taii,fornia Date: 6-20-03 Borine No. 6 Job No.: 544-3272 DESCRIPTION H A c a REMARKS E u U CA CO) U 0 Artificial Fill; Silty Sand: SM, Fill upper 2 - 3' Brown, fine grained 5 4/4/4 Silty Sand: Brown, SM --- 17% passing #200 fine grained 10 6/10/14 Sandy Silt: Brown, ML --- 2 --- 53% passing #200 very sandy 15 6/12/18 Clayey Silt: Brown with thin IVIL --- 3 --- 65% passing #200 interbedded silty sand layers 20 Sandy Silt: Brown, IVIL - 8/10/12 slightly clayey 64% passing #200 Total Depth = 21.5' Recovered Sample No Bedrock - No Groundwater 25 30 35 40 45 50 - Note: The stratification lines 55 represent the approximate boundaries between the soil types; the transitions may be gradual. i. ._ _ .. ._ _ _ __.._.__ ._._. _ .. . _ ___. ___.. _..._._. __ . ___......._.,_...._�_..._ .._ __ _. _ w......._......,..�.._ , ..., .. __ ..�_.�....�. APPENDIX B Laboratory Testing Laboratory Test Results _0 APPENDIX B LABORATORY TESTING Representative bulk and relatively undisturbed soil samples were obtained in the field and returned to our laboratory for additional observations and testing. Laboratory testing was generally performed in two phases. The first phase consisted of testing in order to determine the compaction of ' the existing natural soil and the general engineering classifications of the soils underlying the site. This testing was performed in order to estimate the engineering characteristics of the soil and to serve as a basis for selecting samples for the second phase of testing. The second phase consisted of ' soil mechanics testing. This testing including consolidation, shear strength and expansion testing was performed in order to provide a means of developing specific design recommendations based on the mechanical properties of the soil. CLASSIFICATION AND COMPACTION TESTING Unit Weight and Moisture Content Determinations: Each undisturbed sample was weighed and ' measured in order to determine its unit weight. A small portion of each sample was then subjected to testing in order to determine its moisture content. This was used in order to determine the dry density of the soil in its natural condition. The results of this testing are shown on the Boring Logs. Maximum Density-Optimum Moisture Determinations: Representative soil types were selected for maximum density determinations. This testing was performed in accordance with the ASTM Standard D1557 -91, Test Method A. The results of this testing are presented graphically in this appendix. The maximum densities are compared to the field densities of the soil in order to determine the existing relative compaction to the soil. This is shown on the Boring Logs, and is useful in estimating the strength and compressibility of the soil. Classification Testing: Soil samples were selected for classification testing. This testing consists of mechanical grain size analyses and Atterberg Limits determinations. These provide information for developing classifications for the soil in accordance with the Unified Classification System. This classification system categorizes the soil into groups having similar engineering characteristics. The results of this testing are very useful in detecting variations in the soils and in selecting samples for further testing. SOIL MECHANIC'S TESTING Direct Shear Testing: One bulk sample was selected for Direct Shear Testing. This testing measures the shear strength of the soil under various normal pressures and is used in developing parameters for foundation design and lateral design. Testing was performed using recompacted test specimens, which were saturated prior to testing. Testing was performed using a strain controlled test apparatus with normal pressures ranging from 800 to 2300 pounds per square foot. Expansion Testing: One bulk sample was selected for Expansion testing. Expansion testing was performed in accordance with the UBC Standard 18-2. This testing consists of remolding 4 -inch diameter by 1-inch thick test specimens to a moisture content and dry density corresponding to approximately 50 percent saturation. The samples are subjected to a surcharge of 144 pounds per square foot and allowed to reach equilibrium. At that point the specimens are inundated with distilled water. The linear expansion is then measured until complete. Consolidation Testing: Four relatively undisturbed samples were selected for consolidation testing. For this testing one-inch thick test specimens are subjected to vertical loads varying from 575 psf to 11520 psf applied progressively. The consolidation at each load increment was recorded prior to placement of each subsequent load. The specimens were saturated at the 575 psf or 720 psf load increment. Maximum Density /Optimum Moisture ASTM D698/D1557 145 140 135 130 125 .r A 120 L 115 110 AAov n,A city 10s 100 Sieve Size 3/4" 3/8" #4 % Retained Ju ,y 9, 2003 ASTM D -1557 A Rammer Type: Machine IM� --- k ' < Zero Air Voids Lines, 'm MR- 9 m- -mmmm. 0 5 10 15 20 25 Moisture Content, % Sladden Engineering Revised 12103/02 Project Number: 544 - 3272__,® ' Project Name: Tract 31249 Lab ID Number: Sample Location: Bulk 1 @ 0 -5' ' Description: Silty Sand Maximum Density: 108 pcf ' Optimum Moisture 15.5% 145 140 135 130 125 .r A 120 L 115 110 AAov n,A city 10s 100 Sieve Size 3/4" 3/8" #4 % Retained Ju ,y 9, 2003 ASTM D -1557 A Rammer Type: Machine IM� --- k ' < Zero Air Voids Lines, 'm MR- 9 m- -mmmm. 0 5 10 15 20 25 Moisture Content, % Sladden Engineering Revised 12103/02 Maximum Density /Optimum Moisture ASTM D698/D1557 Project Number: 544 3,272 Project Name: Tract 31249 Lab ID Number: Sample Location: Bulk 3 @ 0 -5' (Max Only) Description: Sandy Silt Maximum Density: 117.5 pef Optimum Moisture 12.5% Sieve Size % Retained 3/4" 3/8" #4 145 140- 135 - 130 - V C 125 T C v A 120- L Q 115- 110 105 inn July 9, 2003 ASTM D -1557 A Rammer Type: Machine V 0 5 10 15 Moisture Content, % 20 25 Max Density Sladden Engineering Revised 12/03/02 Direct Shear ASTM D 3080 -90 (modified for unconsolidated, undrained conditions) Job Number 544 -3272 Job Name Tract 31249 Lab ID No. 3 Sample ID Bulk 1 @ 0 -5' Classification Silty Sand Sample Type Remolded @ 90% of Maximum Density July 9, 2003 Initial Dry Density: 104.3 pcf Initial Mosture Content: 15.5 % Peak Friction Angle (0): 31' Cohesion (c): 40 psf Test Results 1 2 3 4 Average Moisture Content, % 21.2 21.2 21.2 21.2 21.2 Saturation, % 92.7 92.7 92.7 92.7 92.7 Normal Stress, kips 0.151 0.301 0.603 1.206 Peak Stress, kips 0.126 1 0.234 0.369 0.765 • Peak Stress Linear (Peak Stress) 12 1.0 0.8 I 0.4 0.2 0.0 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 Normal Stress Direct Shear Sladden Engineering Revised 12/03/02 F . Job Number: 544 -3272 Job Name: Tract 31249 Sample ID: Boring 1 @ 5' Soil Description: Silty Sand 1 0 -2 -3 -4 -5 -6 -7 -8 -9 -10 One Dimensional Consolidation ASTM D2435 & D5333 July 9, 2003 Initial Dry Density, pcf: 109.2 Initial Moisture, %: 1 Initial Void Ratio: 0.526 Specific Gravity: 2.67 % Change in Height vs Normal Presssure Diagram —�— Before Saturation After Saturation I - 9 Rebound —* —Hydro Consolidation j 0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 Consolidation SIadden Engineering Revised 11/20/02 Job Number: 544 -3272 Job Name: Tract 31249 Sample ID: Boring 3 @ 5' Soil Description: Sandy Silt i -2 -3 -4 -5 -6 -7 -8 -9 -10 [i ~ One Dimensional Consolidation ASTM D2435 & D5333 �e July 9, 2003 Initial Dry Density, pef: 85.8 Initial Moisture, %: 7 Initial Void Ratio: 0.943 Specific Gravity: 2.67 % Change in Height vs Normal Presssure Diagram i -9-- Before Saturation A After Saturation $- Rebound -A -Hydro Consolidation 0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 Consolidation Sladden Engineering Reviscd 11/20/02 One Dimensional Consolidation ASTM D2435 & D5333 Job Number: 544 -3272 July 9, 2003 Job Name: Tract 31249 Initial Dry Density, pcf: 89.2 Sample ID: Boring 5 @ 10' Initial Moisture, %: 2 Soil Description: Silty Sand Initial Void Ratio: 0.870 Specific Gravity: 2.67 Hydrocollapse: 1.0% @ 0.575 ksf I 0 -1 -2 -3 -4 -5 -6 -7 -8 -9 -10 0.0 0.5 % Change in Height vs Normal Presssure Diagram — 0 Before Saturation A After Saturation E) Rebound —f —Hydro Consolidation 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 Consolidation Sladden Engineering Revised 11/20/02 Job Number: 544 -3272 ' Job Name: Tract 31249 Sample ID: Boring 7 @ 10' ' Soil Description: Silty Sand One Dimensional Consolidation ASTM D2435 & D5333 July 9, 2003 Initial Dry Density, pcf: 93.4 Initial Moisture, %: 1 Initial Void Ratio: 0.785 Specific Gravity: 2.67 I% Change in Height vs Normal Presssure Diagram 0 Before Saturation - A After Saturation 9 Rebound —1111—Hydro Consolidation 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 Consolidation Sladden Engineering Revised 11/20/02 ' 0 ' -2 -3 i -4 -5 -6 -7 -8 ' -9 ' -10 0 Before Saturation - A After Saturation 9 Rebound —1111—Hydro Consolidation 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 Consolidation Sladden Engineering Revised 11/20/02 i 100 Gradation ASTM C117 & C136 Project Number: 544 -3272 July 9,A03 Project Name: Tract 31249 Sample ID: Bulk 1 @ 0 -5' Sieve Sieve Percent Size, in Size, mm Passing 90 1 " 25.4 100 3/4" 19.1 100 1/2" 12.7 100 3/8" 9.53 100 #4 4.75 100 #8 2.36 100 916 1.18 100 #30 0.60 100 950 0.30 88 4100 0.15 35 9200 0.074 11 100 90 ill 80 70 - -i -i- 60 ! ( 50 cam, \ 40 30 _ I 1 F1 I 1 11 1 A IIII__ 20 ! ±I 10 L i 0 I I ; II II E� 100.0 10.0 1.0 0.1 0.0 0.0 Sieve Size, mm Gradation Sladden Engineering Revised 11/20/02 Gradation ASTM C117 & C136 Project Number: 544 -3272 Project Naine: Tract 31249 Sample ID: Boring 1 @ 5' 10o Sieve Sieve Percent Size, in Size, mm. Passing 1" 25.4 100 3/4" 19.1 100 1/2" 12.7 100 3/8" 9.53 100 #4 4.75 100 #8 2.36 100 416 1.18 100 #30 0.60 100 450 0.30 86 #100 0.15 34 #200 0.074 9 fuly 9, 2003 Gradation Sladden Engineering Revised 11/20/02 10o I ! 90 III I 80 ! i ! 70 III f I 60 50 nom. 40 30 I I I I J I,II I I i I l I _� ILT I. I I IIJ I I I I— I I t I I II 20 ILIL 1 11 1 ` - 10 - 1 -1 -1 Ili 0 I I i-1 I! I - I I 100.0 10.0 1.0 0.1 0.0 0.0 Sieve Size, mm Gradation Sladden Engineering Revised 11/20/02 Gradation ASTM Cl 17 & C136 Project Number: 544 -3252 Project Name: Tract 31249 Sample ID: Boring 3 @ 10' Sieve Sieve Percent Size, in Size, mm Passing 1" 25.4 100 3/4" 19.1 100 1/2" 12.7 100 3/8" 9.53 100 #4 4.75 100 #8 2.36 100 #16 1.18 100 #30 0.60 83 #50 0.30 39 #100 0.15 16 #200 0.074 8 -" July 9, 2003 100 v 90 I I - i i 80 70 can 60 I I I N Cq a 50 40 30 I 20 I — 10 I, I -1— r -- 1 1 I 0 I I 1 1 1 1---1 'IT 100.0 10.0 1.0 0.1 0.0 0.0 Sieve Size, mm Gradation Sladden Engineering Revised 11/20/02 ' Gradation ASTM C1 17 & C136 Project Number: 544 -3272 a Project Name: Tract 31249 ' Sample ID: Boring 7 @ 5' Sieve Sieve Percent Size, in Size, mm Passing 1" 25.4 100 3/4" 19.1 100 1/2" 12.7 100 ' 3/8" 9.53 100 #4 4.75 100 #8 2.36 100 #16 1.18 100 #30 0.60 100 950 0.30 97 ' 9100 0.15 65 9200 0.074 23 July 9, 2003 100 90 80 70 1 1 on 60 I — a 50 —� 40 I I f1�1 i 1 30 I I I III I 1 1 20 _ I I I I I _ 10 I i _H I i I 100.0 10.0 1.0 0.1 0.0 0.0 Sieve Size, mm ' Gradation Sladden Engineering Revised 11/20/02 hi u k4ZS.E. "4 Expansion Index ASTM D 4829AJBC 29 -2 Job Number: 544 -3272 Date Job Name: Tract 31249 Tech Lab ID: Sample ID: Bulk 1 @ 0 -5' Soil Description: Silty Sand Wt of Soil + Ring: 525.0 Weight of Ring: 179.0 Wt of Wet Soil: 346.0 Percent Moisture: 15% Wet Density, pcf: 7/10/03 104.8 Dry Denstiy, pcf: 0.500 91.2 0.500 Saturation: 47.7 Expansion Rack # Date /Time 7/10/03 1 7:30 A.M. Initial Reading 0.500 Final Reading 0.500 Expansion Index (Final -Initial) x 1000 0 7/9/03 Jake El Sladden Engineering Revised 12/10/02 APPENDIX C 1997 UBC Seismic Design Criteria August 20, 2003 -12- Project No. 544-3272 03-08-544 1997 UNIFORM BUILDING CODE INFORMATION The International Conference of Building Officials 1997 Uniform Building Code contains substantial revisions and additions to the earthquake engineering section summarized in Chapter 16. Concepts contained in the 1997 code that will be relevant to construction of the proposed structure are summarized below. Ground shaking is expected to be the primary hazard most likely to affect the site, based upon proximity to significant faults capable of generating large earthquakes. Major fault zones considered to be most likely to create strong ground shaking at the site are listed below. Fault Zone Approximate Distance From Site Fault Type (1997 UBC) San Andreas 13.5 km A San Jacinto 27.8 km A Based on our field observations and understanding of local geologic conditions, the soil profile type judged applicable to this site is SD, generally described as stiff or dense soil. The site is located within UBC Seismic Zone 4. The following table presents additional coefficients and factors relevant to seismic mitigation for new construction upon adoption of the 1997 code. Sladden Engineering Near-Source Near-Source Seismic Seismic Seismic Acceleration Velocity Coefficient Coefficient Source Factor, Na Factor, N,. Ca Cv San Andreas 1.0 1.05 0.44 Na 0.64 N,. San Jacinto 1.0 1.0 0.44 Na 0.64 N,. Sladden Engineering JOB NUMBER: 544 -3272 * * * E Q F A U L T * * Version 3.00 * * * * * * * * * * * * * * * * * * * * * * ** DETERMINISTIC ESTIMATION OF PEAK ACCELERATION FROM DIGITIZED FAULTS DATE: 07 -12 -2003 JOB NAME: Proposed Residential Development Tentative Tract 31249 La Quinta, California CALCULATION NAME: Test Run Analysis FAULT- DATA -FILE NAME: CDMGFLTE.DAT SITE COORDINATES: SITE LATITUDE: 33.6263 SITE LONGITUDE: 116.2568 SEARCH RADIUS: 100 mi ATTENUATION RELATION: 5) Boore et al. (1997) Horiz. - SOIL (310) UNCERTAINTY (M= Median, S= Sigma): M Number of Sigmas: 0.0 DISTANCE MEASURE: cd_2drp SCOND: 0 Basement Depth: 5.00 km Campbell SSR: Campbell SHR: COMPUTE PEAK HORIZONTAL ACCELERATION FAULT -DATA FILE USED: CDMGFLTE.DAT MINIMUM DEPTH VALUE (km): 0.0 _A --------- - - - - -- EQFAULT SUMMARY --------- - - - - -- -A ----------------------------- DETERMINISTIC SITE PARAMETERS ----------------------- - - - - -- Page 1 I (ESTIMATED MAX. EARTHQUAKE EVENT I APPROXIMATE I------------------------------- ABBREVIATED I DISTANCE I MAXIMUM I PEAK JEST. SITE FAULT NAME I mi (km) (EARTHQUAKE( SITE (INTENSITY I I MAG.(Mw) I ACCEL. g JMOD.MERC. SAN ANDREAS - Coachella 1 8.4( 13.5)1 7.1 1 0.283 1 IX SAN ANDREAS - Southern 1 8.4( 13.5)1 7.4 1 0.332 1 IX SAN JAACINTO-ANZA 1 17.3( 27.8)1 7.2 1 0.178 1 VIII SAN JACINTO- COYOTE CREEK 1 18.5( 29.7)1 6.8 1 0.137 1 VIII BURNT MTN. 1 23.1( 37.1)) 6.4 1 0.094 1 VII EUREKA PEAK 1 24.0( 38.6)1 6.4 1 0.091 1 VII SAN ANDREAS - San Bernardino 1 24.2( 38.9)1 7.3 1 0.146 1 VIII SAN JACINTO - BORREGO 1 29.7( 47.8)1 6.6 1 0.086 1 VII PINTO MOUNTAIN 1 35.7( 57.5)1 7.0 1 0.092 1 VII EARTHQUAKE VALLEY 1 36.0( 57.9)1 6.5 J 0.070 1 VI EMERSON So. - COPPER MTN. 1 36.9( 59.4)1 6.9 1 0.085 1 VII BRAWLEY SEISMIC ZONE 1 37.1( 59.7)1 6.4 1 0.065 1 VI PISGAH- BULLION MTN. - MESQUITE L•K 1 38.2( 61.4)1 7.1 1 0.092 J VII LANDERS 1 38.2( 61.5)1 7.3 1 0.103 1 VII SAN JACINTO -SAN JACINTO VALLEY 1 38.8( 62.4)1 6.9 J 0.082 1 VII ELSINORE- JULIAN 1 40.0( 64.4)1 7.1 1 0.089 1 VII NORTH FRONTAL FAULT ZONE (East) 1 43.1( 69.3)1 6.7 1 0.083 1 VII ELMORE RANCH 1 44.1( 70.9)1 6.6 1 0.064 1 VI ELSINORE- COYOTE MOUNTAIN 1 46.1( 74.2)1 6.8 1 0.068 1 VI ELSINORE- TEMECULA 1 46.8( 75.3)1 6.8 1 0.067 J VI SUPERSTITION MTN. (San Jacinto) 1 47.8( 76.9)1 6.6 1 0.060 1 VI SUPERSTITION HILLS (San Jacinto)( 48.7( 78.4)1 6.6 1 0.059 1 VI JOHNSON VALLEY (Northern) 1 49.0( 78.9)1 6.7 1 0.062 1 VI CALICO - HIDALGO 1 50.6( 81.4)1 7.1 1 0.074 1 VII NORTH FRONTAL FAULT ZONE (West) 1 54.7( 88.0)1 7.0 1 0.081 1 VII LENWOOD- LOCKHART -OLD WOMAN SPRGSI 54.7( 88.1)1 7.3 1 0.078 1 VII HELENDALE - S. LOCKHARDT 1 62.4( 100.4)1 7.1 1 0.063 1 VI SAN JACINTO -SAN BERNARDINO 1 62.5( 100.6)1 6.7 1 0.051 1 VI ELSINORE -GLEN IVY 1 62.8( 101.0)1 6.8 1 0.054 1 VI IMPERIAL 1 63.2( 101.7)1 7.0 1 0.059 1 VI LAGUNA SALADA 1 65.9( 106.1)1 7.0 1 0.057 1 VI CLEGHORN 1 70.9( 114.1)1 6.5 1 0.042 1 VI ROSE CANYON 1 74.4( 119.8)1 6.9 J 0.050 1 VI NEWPORT- INGLEWOOD (Offshore) 1 74.9( 120.5)1 6.9 1 0.049 1 VI CHINO- CENTRAL AVE. (Elsinore) 1. 76.7( 123.5)1 6.7 1 0.053 1 VI CUCAMONGA 1 77.9( 125.4)1 7.0 1 0.061 1 VI WHITTIER 1 81.0( 130.3)1 6.8 1 0.044 1 VI SAN ANDREAS - Mojave 1 87.2( 140.3)1 7.1 1 0.049 1 VI SAN ANDREAS - 1857 Rupture 1 87.2( 140.3)1 7.8 1 0.070 1 VI SAN JOSE 1 89.1( 143.4)1 6.5 1 0.042 1 VI ----------------------------- DETERMINISTIC SITE PARAMETERS ---------------------- - - - - -- Page 2 I {ESTIMATED MAX. EARTHQUAKE EVENT I APPROXIMATE I------------------=------------ ABBREVIATED I DISTANCE I MAXIMUM I PEAK JEST. SITE FAULT NAME I mi (km) IEARTHQUAKEI SITE JINTENSITY I I MAG.(Mw) I ACCEL. g JMOD.MERC. CORONADO BANK 1 89.2( 143.5)1 7.4 1 0.056 J VI SIERRA MADRE 1 92.0( 148.0)1 7.0 1 0.054 1 VI ELYSIAN PARK THRUST 1 93.5( 150.5)1 6.7 1 0.045 J VI GRAVEL HILLS - HARPER LAKE J 94.1( 151.5)1 6.9 J 0.041 J V NEWPORT - INGLEWOOD (L.A.Basin) J 95.9( 154.4)1 6.9 1 0.041 J V COMPTON THRUST 1 99.5( 160.1)1 6.8 J 0.046 1 VI PALOS VERDES 1 99.7 ( 160.4)1 7.1 J 0.044 1 VI * * k * + * * * * * * * * * * k k : .. - x * * * * * * * * k * k k * * * * * k * k k * * * + * * .I .:. ,- k * * * * * * * * * * k t: k * * * * * -END OF SEARCH- 47 FAULTS FOUND WITHIN THE SPECIFIED SEARCH RADIUS. THE SAN ANDREAS - Coachella FAULT IS CLOSEST TO THE SITE IT IS ABOUT 8.4 MILES (13.5 km) AWAY. LARGEST MAXIMUM - EARTHQUAKE SITE ACCELERATION: 0.3319 g i i i i CALIFORNIA FAULT MAP Tentative Tract 31249 / La Quinta, CA 100 000 900 800 700 600 500 400 300 200 100 �� ITE o � � 0 100 -400 -300 -200 -100 0 100 200 300 400 500 600 0 c� a� a� U U i 3 _of a STRIKE -SLIP FAULTS 5) Boore et al. (1997) Horiz. - SOIL (3 10) M =5 M =6 M =7 M =8 1 .1 .01 .001 1 10 100 Distance [adist] (km) rx 0 c� a� a� U U i 3 _0, DIP -SLIP FAULTS 5) Boore et al. (1997) Horiz. - SOIL (3 10) M =5 M =6 M =7 1 .1 .01 .001 1 10 100 Distance [adist] (km) 01 0 co L U U I BLIND - THRUST FAULTS 5) Boore et al. (1997) Horiz. - SOIL (3 10) M =5 M =6 M =7 M =8 1 1 01 M 1 10 100 Distance [adist] (km) n 0 co a� a� U U i MAXIMUM EAR711QUAKE S Tentative Tract 31249 / La Quinta, CA 1 .1 .01 .001 .1 1 10 100 Distance (mi) EARTHQUAKE MAGNITUDES & DISTANCES Tentative Tract 31249 / La Quinta, CA 7.75 7.50 7.25 a� c 7.00 c� 6.75 6.50 .1 .1 10 100 Distance (mi) .Ct