Loading...
23935 Topaz1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. CITY OF LA QUINTA DRAINAGE & RETENTION STUDY TRACT 23935 SOUTHWEST CORNER OF DUNE PALM & MILES TABLE OF CONTENTS: Narrative & Explanation of Methodology 100 Year Rational Hydrology 10 Year Rational Hydrology Hydrology Map Rainfall Storage Analysis - 10 Year Rainfall Rainfall Storage Analysis - 100 Year Rainfall Graph of Rainfall/Retention Analysis - Q100 Infiltration Rates Developed by Leighton & Associates Retention Basin Sizing Retention Basin Map RCFC Plates Used %rvices, munity gineering is Inc. As part of the conditions of approval of Tract 23935, the rainwater runoff 100 year storm event must be retained and disposed of within the site of the proposed subdivision. In order to obtain the above goal, several items must be studied. These items follow: 1. Development of a storm intensity, runoff quantities for the required storm event. Please refer to Attachments 2, 3, and 4. The Q100 flows were calculated at 106.64 CFS using the rational hydrology method. Q10 = 58.53 CFS was also developed. From these quantities of runoff a 24 hour storm volume was developed using RCFC methodology - see plates attached. This incremental volume has been shown as a percentage of the peak runoff in Attachments 5, 6, • and 7. The hourly and total runoff volumes are also shown. 2. Volume of storage needed is a function of the runoff volumes less the expected ground percolation rates. To calculate the percolation rates several assumptions have been made: a) Bare ground percolation rate to be the rate developed by the Leighton report, Attachment 8, and that the retention basin side slopes be planted with non -dense ground cover to retain the bare ground status. b) Basin bottoms to be grassed with a percolation rate of 2" per hour per the tests by Buena Engineering. C) Leach line and drywell percolation rates are to be the same as bare ground. Leach lines area to be subtracted from the grassed area and no sidewall rates have been included in leach line calculation. The graph and tables show the total percolation of the retention basin area. Please notice that until hour eleven the entire runoff is expected to percolate and no storage is required. 3. A maximum volume of 139,213 cubic feet of storage is needed based on a 24 hour, 100 year event. Utilizing a basin less than seven feet deep • (6.98') x 95'± wide x 292'± long with side slopes varying from 2:1 to 5:1 a volume of 139,321 cubic feet of storage has been generated. 5225 CANYON CREST DR. • SUITE 252 • RIVERSIDE, CA 92507 • (714) 781-0950 The calculations are as follows: Total Area Bottom Grass Area Side Slope Area Volumes: Bottom Sides 12,210 x 6.98 = 15,500 x 6.98/2 = TOTAL RETENTION AVAILABLE PEAK RETENTION NEEDED 27,710 SF 12,210 SF 15,500 SF 85,226 CF 54,095 CF 139,321 CF 120,398 CF 4. The attached basin design will utilize 2:1 to 5:1 side slopes with a grassed area of 50' x 250' for use as a small local park. The landscape plans will be submitted for review upon approval of the above report. Since the basin has 4:1 to 5:1 slopes along the street frontage no fence is proposed along Desert Stream Drive. Along the remaining sides of the basins a six foot block wall will be constructed. In summary, the hundred year storm would be contained within the basin and the ten year event would percolate within the system with no standing water in the basin at the end of the storm. The residual 100 year runoff would percolate out of the basin in about four hours. This design approach is quite conservative as the hydrology assumes the ground is previously watered, the leach lines have no sidewall calcs and the percolation rates have a conservative 1.5 safety factor applied. • RIVERSIDE COUNTY R A T I O N A L- H Y D R O L O G Y PROGRAM PACKAGE Copyright_ (c) CivilCadd/CivilDesign, 1988 Rational Hydrology Study I Date: 11-27-89 11/17/89 100 year hydrology for tract 23935 hydrograph reflects 24 hour precipitation in a hundred year occurence *SPECIFIED HYDROLOGY INFORMATION* Rational method hydrology program based on Riverside County Flood Control & Water Conservation District 1978 Hydrology Manual Storm Event(Year) = 100.00 Antecedent Moisture Condition = 2 Standard Intensity -Duration Curves Data (Plate 0-4.1) for the CATHEDRAL CITY area used. 10 Year Storm 10 Minute Intensity(In./Hr.) = 2.770 10 Year Storm 60 Minute Intensity(In./Hr.) = .980 W0 Year Storm 10 Minute Intensity(In./Hr.) = 4.520 OO Year Storm 60 Minute Intensity(In./Hr.) = 1.600 Calculated Rainfall Intensity Data: 1 Hour Intensity(In./Hr.) = 1.6000 Slope of Intensity Duration Curve = .5800 Storm Year = 100. + + + + + + + + + + + + + + + + + + + + + + + + .. + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + Process from Point/Station 1.01 to Point/Station 1.02 *** INITIAL AREA EVALUATION *** Assummed Initial Subarea Uniform Area Type is: Single Family (1/4 Acre) TC = K*[(Length"3)/(Elevation Change)] -.2 Initial Subarea Flow Dist. = 930.00 Upstream Elevation = 85.00 Downstream Elevation = 72.00 Elevation Difference = 13.00 TC = .390*[( 930.00**3)/( 13.00)]**.2 = 14.105 100.00 Year computed rainfall (In./Hr.) _- 3.705 Decimal Fraction Soil Group A = 1.000 Decimal Fraction Soil - Group B = .000 Decimal Fraction Soil Group C = .000 Decimal Fraction Soil GroLrp D = .000 0 Ingle farnily(1/4 Acre lot) runoff coefficient = .7050 unoff Index for AMC2 = 32.00 Effective Runoff Coefficient used (Q=CIA) is C = .705 Subarea runoff (CFS) = 20:90 Total area(ACRES) = 8.00 ++++++++++++++++++++++++++++++++++++++++i-++++++++++++++++++++++++++++++++++ *** STREET FLOW TRAVEL TIME + SUBAREA FLOW ADDITION *** Upstream Elevation (Ft.) = 72.00 Downstream Elevation (Ft.) = 58.00 Street Length (Ft.) = 730.00 Curb Height (In.) = 6. Street Halfwidth (Ft.) = 20.00 istance From Crown to Crossfall Grade Break lope from Gutter to Grade Break (Ft./Ft.) = Slope from Grade Break to Crown (Ft./Ft.) = Number of Halfstreets Carryinq Runoff = 2 Distance from curb to property line (Ft.) _ Slope from curb to property line (Ft./Ft.) = Gutter width (Ft.) = 2.000 (Ft.) = 18.00 .020 .020 10.00 .020 Gutter hike (distance above flow line) = 2.000 (In.) Estimated mean flow rate at MIDPOINT of street = 29.91 (CFS) Depth of flow = .51 (Ft.) Average Velocity = 3.95 (Ft./Sec.) WARNING: DEPTH OF FLOW EXCEEDS TOP OF CURB Distance that curb overflow reaches into property is = .452 (Ft.) Streetflow Hydraulics at MIDPOINT of street travel Halfstreet Flow Width(Ft.) = 20.00 Flow Velocity(Ft./Sec.) = 3.95 Depth*Velocity = 2.01 Travel time (Min.) = 3.08 TC(min.) = 17.18 Adding Area Flow To Street 00.00 Year computed rainfall (In./Hr.) = 3.304 ecimal Fraction Soil Group A = 1.000 Decimal Fraction Soil Group B = .000 Decimal Fraction Soil Group C = .000 Decimal Fraction Soil Group D = .000 Single family(1/4 Acre lot) runoff coefficient = .6923 Runoff Index for AMC2 = 32.00 Subarea runoff = 15.78 (CFS) for 6.90 Acres Total runoff = 36.68 (CFS), Total area = 14.90 Acres Depth of flow = .54 (Ft.) Average Velocity = 4.13 (Ft./Sec.) WARNING: DEPTH OF FLOW EXCEEDS TOP OF CURB NOTE: Depth of flow exceeds top of crown. Distance that curb overflow reaches into property is = 2.026 (Ft.) Streetflow Hydraulics at ENDPOINT of street travel Halfstreet Flow Width(Ft.) = 20.00 Flow Velocity(Ft./Sec.) = 3.95 Depth*Velocity = 2.14 ++++++++ i-+ -i-+++++ i-+++++ t-H++++-F+++++++++++++++++++++++++++t++++++ .4• +++++++++++ Process from Point/Station 1.02 to Point/Station 2.01 ** CONFLUENCE OF MAIN STREAMS *** FOLLOWING DATA INSIDE MAIN STREAM ARE CALCULATED 100.00 Year computed rainfall (In./Hr.) = 3.304 Total flow area (Acres) = 14.90 Total runoff (CFS) at confluence point = 36.68 Program is now starting with MAIN STREAM NO. 2 ++++++++++++++++++++++++++++++++++++f++++++++++++++++++++++++++++++++++++ rocess from Point/Station 3.01 to Point/Station 3.02 *** INITIAL AREA EVALUATION *** Assummed Initial Subarea Uniform Area Type is: Single Family (1/4 Acre) TC = K*[(Length"3)/(Elevation Change)] -.2 Initial Subarea Flow Dist. = 1000.00 Upstream Elevation = 78.00 Downstream Elevation = 66.00 Elevation Difference = 12.00 TC = .390*[( 1000.00**3)/( 12.00)]**.2 = 14.970 100.00 Year computed rainfall (In./Hr.) = 3.579 Decimal Fraction Soil Group A = 1.000 Decimal Fraction Soil Group B = .000 Decimal Fraction Soil Group C = .000 Decimal Fraction Soil Group D = .000 Single family(1/4 Acre lot) runoff coefficient - .7012 Runoff Index for AMC2 = 32.00 Effective Runoff Coefficient used (Q=CIA) is C = .701 Subarea runoff (CFS) = 24.60 Total area(ACRES) = 9.80 +++++++++++++++++--+++++++++++++,•++++++++++++++++++++++++++++++++++++++++++ rocess from Point/Station 3.01 to Point/Station 3.02 *** CONFLUENCE OF MINOR STREAMS *** 100.00 Year computed rainfall (In./Hr.) = 3.579 ALONG THE MAIN STREAM NUMBER: 2 The flow values used for the stream: 1 are: Time of c:oncentration(min.) = 14.97 Rainfall intensity (in./hr/) = 3.58 Total flow area (Acres) = 9.80 Total runoff (CFS) at confluence point - 24.60 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 4.01 to Point/Station 4.02 *** INITIAL AREA EVALUATION *** Assummed Initial Subarea Uniform Area Type is: Single Family (1/4 Acre) TC = K*[(Length"3)/(Elevation Change)) -.2 Initial Subarea Flow Dist. = 880.00 Upstream Elevation = 76.00 lownstream Elevation = 63.00 levation Difference = 13.00 TC = .390*[( 880.00**3)/( 13.00)]**.2 = 13.645 100.00 Year computed rainfall (In./Hr.) = 3.777 Decimal Fraction Soil Group A = 1.000 Decimal Fraction Soil Group B = .000 Decimal Fraction Soil Group C = .000 jingie Tamllykl/'1 more LoLJ r-urru1 1 Runoff Index for AMC2 = 32.00 Effective Runoff Coefficient used Subarea runoff (CFS) = 13.09 Total area(ACRES) = 4.90 1I V 1'r 1 1 1 Lr 1 G 1 1 I (Q=CIA) is C = .707 0++4.++++++++++++++++++++++++++++++++++++++++++++++++++.i.+++++++++.r.++++++++++ Process from Point/Station 4.01 to Point/Station 4.02 *** CONFLUENCE OF MINOR STREAMS ***' *** Compute Various Confluenced Flow Values *** 100.00 Year computed rainfall (In./Hr.) = 3.777 ALONG THE MAIN STREAM NUMBER: 2 The flow values used for the stream: Time of concentration(min.) 13.64 Rainfall intensity (in./hr/) = 3.78 Total flow area (Acres) = 4.90 Total runoff (CFS) at confluence point 2 are: 13.09 Confluence information: $tream runoff Time Intensity Number (CFS) (min.) (inch/hour) -------------=-------------------------------------------------- 1 24:60 14.97 3.579 2 13.09 13.64 3.77.7 QSMX(1) = +1.000*1.000* 24.6) 948*1.000* 13.1) _• 36.999 QSMX(2) = +1.000* .911* 24.6) +1.000*1.000* 13.1) = 35.506 Rainfall intensity and time of concentration used for 2 streams. Individual stream flow values are: 24.60 13.09 Possible Confluenced flow values are: 37.00 35.51 Individual'Stream Area values are: 9.80 4.90 Computed confluence estimates are: Runoff(CFS) = 37.00 Time(min.) = 14.970 Total main stream study area (Acres) = 14.70 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 4.02 to Point/Station 5.01 *** STREET FLOW TRAVEL TIME + SUBAREA FLOW ADDITION w*w Upstream Elevation (Ft.) = 63.00 Downstream Elevation (Ft.) 60.00 �treet Length (Ft.) = 700.00 Curb Height (In.) = B. Street Halfwidth (Ft.) = 20.00 Distance From Crown to Crossfall Grade Break (Ft.) = 18.00 Slope from Gutter to Grade Break (Ft./Ft.) = .020 Slope from Grade Break to Crown (Ft./Ft.) = .020 .. . I - _ - .. - ..._ ._ -- -..__.pf _ n k3ui_Ler wiaLn krk- .) - Gutte,r hike (distance above flow line) = 2.000 (In.) Estimated mean flow rate at MIDPOINT of street Depth of flow = .71 (Ft.) 81verage Velocity 2.98 (Ft./Sec.) WARNING: DEPTH OF FLOW EXCEEDS TOP OF CURB NOTE: Depth of flow exceeds top of crown. Distance that curb overflow reaches into property Streetflow Hydraulics at MIDPOINT of street travel Halfstreet Flow Width(Ft.) = 20.00 Flow Velocity(Ft./Sec.) = 2.98 Depth*Velocity = Travel time (Min.) = 3.91 TC(min.) 18.88 Adding Area Flow To Street 46.81 (CFS) is = 2.188 (Ft.) 2.12 100.00 Year computed rainfall (In./Hr.) = 3.128 Decimal Fraction Soil Group A = 1.000 Decimal Fraction Soil Group B = .000 Decimal Fraction Soil Group C = .000 Decimal Fraction Soil Group D = .000 Single family(1/4 Acre lot) runoff coefficient = .6861 Runoff Index for AMC2 = 32.00 Subarea runoff = 16.74 (CFS) for 7.80 Acres Total runoff = 53.74 (CFS), Total area = 22.50 Acres Depth of flow = .74 (Ft.) Average Velocity = 3.11 (Ft./Sec.) aARNING: DEPTH OF FLOW EXCEEDS TOP OF CURB NOTE: Depth of flow exceeds top of crown. Distance that curb overflow reaches into property is = 3.873 (Ft.) Streetflow Hydraulics at ENDPOINT of street travel Halfstreet Flow Width(Ft.) = 20.00 Flow Velocity(Ft./Sec.) = 2.98 Depth*Velocity = 2.22 +++++++++++++++++++++++++.I-+++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 5.01 to Point/Station 6.01 *** STREET FLOW TRAVEL TIME + SUBAREA FLOW ADDITION *** Upstream Elevation (Ft.) = 60.00 Downstream Elevation (Ft.) = 58.00 Street Length (Ft.) = 600.00 Curb Height (In.) = 8. Street Halfwidth (Ft.) = 20.00 Distance From Crown to Crossfall Grade Break Slope from Gutter to Grade Break (Ft./Ft.) = Slope from Grade Break to Crown (Ft./Ft.) = Number of Halfstreets Carrying Runoff = 2 Distance from curb to property line (Ft.) _ Slope -from curb to property line (Ft./Ft.) = Gutter width (Ft.) = 2.000 (Ft.) = 18.00 .020 .020 10.00 .020 utter hike (distance above flow line) = 2.000 (In.) Estimated mean flow rate at MIDPOINT of street = 58.16 (CFS) Depth of flow = .80 (Ft.) Average Velocity = 2.92 (Ft./Sec.) NU I t: uep cn o f 'law exceeu5 uop u i u"w+" Distance that curb overflow reaches into property is = 6.534 (Ft.) Streetflow Hydraulics at MIDPOINT of street travel Halfstreet Flow Width(Ft.) = 20.00 Ililow Velocity(Ft./Sec.) = 2.92 Depth*Velocity = 2.33 Travel time (Min.) 3.43 TC(min.) = 22.31 Adding Area Flow To Street 100.00 Year computed rainfall (In./Hr.) = 2.840 Decimal Fraction Soil Group A = 1.000 Decimal Fraction Soil Group B = .000 Decimal Fraction Soil Group C = .000 Decimal Fraction Soil Group D = .000 Single family(1/4 Acre lot) runoff coefficient = .6753 Runoff Index for AMC2 = 32.00 Subarea runoff = 7.10 (CFS) for 3.70 Acres Total runoff = 60.84 (CFS), Total area = 26.20 Acres Depth of flow = .81 (Ft.) Average Velocity = 2.95 (Ft./Sec.) WARNING: DEPTH OF FLOW EXCEEDS TOP OF CURB NOTE: Depth of flow exceeds top of crown. Distance that curb overflow reaches into property is = 7.144 (Ft.) Streetflow Hydraulics at ENDPOINT of street travel Halfstreet Flow Width(Ft.) = 20.00 Flow Velocity(Ft./Sec.) = 2.92 Depth*Velocity = 2.36 1D +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 5.01 to Point/Station 6.01 *** CONFLUENCE OF MAIN STREAMS *** FOLLOWING DATA INSIDE MAIN STREAM ARE CALCULATED 100.00 Year computed rainfall (In./Hr.) = 2.840 The flow values used for the stream: 2 are: Time of concentration(min.) = 22.31 Rainfall intensity (in./hr/) = 2.84 Total flow area (Acres) = 26.20 Total runoff (CFS) at confluence point - 60.84 Program is now starting with MAIN STREAM NO. 3 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 7.01 to Point/Station 7.02 *** INITIAL AREA EVALUATION *** . Assummed Initial Subarea Uniform Area Type is: Single Family (1/4 Acre) TC = K*[(Length"3)/(Elevation Change)] -.2 Initial Subarea Flow Dist. = 800.00 Upstream Elevation = 80.00 Downstream Elevation = 57.00 ueclmal rraQ1-j-uii auil u, uup n = i.vvv Decimal Fraction Soil Group B = .000 Decimal Fraction Soil Group C = .000 Decimal Fraction Soil Group D = .000 Single family(1/4 Acre lot) runoff coefficient .7180 Runoff Index for AMC2 = 32.00 loffective Runoff Coefficient used (Q=CIA) is C .718 ubarea runoff (CFS) = 20.97 Total area(ACRES) = 7.00 ++++++i•++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 7.01 to Point/Station 7.02 *** CONFLUENCE OF MAIN STREAMS *** *** Compute Various Confluenced Flow Values *** ---------------------------------------------------------------------------- FOLLOWING DATA INSIDE MAIN STREAM ARE CALCULATED 100.00 Year computed rainfall (In./Hr.) = 4.172 The flow values used for the stream: 3 are: Time of concentration(min.) = 11.50 Rainfall intensity (in./hr/) = 4.17 Total flow area (Acres) = 7.00 Total runoff (CFS) at confluence point = 20.97 Confluence information: Stream runoff Time Intensity Number (CFS) (min.) (inch/hour) 1 36.68 17.18 3.304 2 60.84 22.31 2.840 3 20.97 11.50 4.172 QSMX(1) = +1.000*1.000* 36.7) +1.000* .770* 60.8) + .792*1.000* 21.0) 100.144 QSMX(2) = + .859*1.000* 36.7) +1.000*1.000* 60.8) + .681*1.000* 21.0) 106.636 Q S M X ( 3 ) = +1.000* .669* 36.7) +1.000* .515* 60.8) +1.000*1.000* 21.0) 76.858 Rainfall intensity and time of concentration used for 3 MAIN streams. Individual stream flow values are: 36.68 60.84 20.97 Possible confluenced flow values are: 100.14 106.64 76.86 individual Stream Area values are: 14.90 26.20 7.00 Computed confluence estimates are: Runoff(CFS) = 106.64 Time(min.) = 22.311 Total main stream study area (Acres) = 48.10 be used for µa�unit �hydrograph study of the same area. TOTAL STUDY AREA(ACRES) = 48.10 AREA AVERAGED PERVIOUS AREA FRACTION(AP) _ .500 AREA AVERAGED SCS CURVE NUMBER (AMC II) a 32.0 . RIVERSIDE COUNTY R A T I 0 N A L. - H Y D R O L O G Y PROGRAM PACKAGE Copyright (c) CivilCadd/CivilDesign, 1988 Rational Hydrology Study Date: 11-27-89 11/27/8 T -------------------------------------- *SPECIFIED HYDROLOGY INFORMATION* Rational method hydrology program based on Riverside County Flood Control & Water Conservation District 1978 Hydrology Manual Storm Event(Year) = 10.00 Antecedent Moisture Condition = 2 Standard Intensity -Duration Curves Data (Plate D-4.1) for the CATHEDRAL CITY area used. �@ Year Storm 10 Minute Intensity(In./Hr.) = 2.770 0 Year Storm 60 Minute Intensity(In./Hr.) = .980 100 Year Storm 10 Minute Intensity(In./Hr.) = 4.520 100 Year Storm 60 Minute Intensity(In./Hr.) = 1.600 Calculated Rainfall Intensity Data: 1 Hour Intensity(In./Hr.) = .9800 Slope of Intensity Duration Curve = .5800 Storm Year = 10. Process from Point/Station 1.01 to Point/Station 1.02 *** INITIAL AREA EVALUATION *** ASSUmmed Initial Subarea Uniform Area Type is: Single Family (1/4 Acre) TC = K*[(Length"3)/(Elevation Change)) -.2 Initial Subarea Flow Dist. = 930.00 Upstream Elevation = 85.00 Downstream Elevation = 72.00 Elevation Difference = 13.00 TC = .390*[( 930.00**3)/( 13.00)]**.2 = 14.105 10.00 Year computed rainfall (In./Hr.) = 2.269 Decimal Fraction Soil Group A = 1.000 Decimal Fraction Soil Group B = .000 Decimal Fraction Soil Group C = .000 ecimal Fraction Soil Group D = .000 ingle family(1/4 Acre lot) runoff coefficient = .6501 Runoff Index for AMC2 = 32.00 Effective Runoff Coefficient used (Q=CIA) is C .650 Subarea runoff (CFS) 11.80 Total area(ACRES) = 8.00 *** INITIAL ARtA tvALUA1IUN Assummed Initial Subarea Uniform Area Type is: Single Family (1/4 Acre) TC = K*[(Length-3)/(Elevation Change)] -.2 nitial Subarea Flow Dist. = 1000.00 pstream Elevation = 78.00 Downstream Elevation = 66.00 Elevation Difference = 12.00 TC = .390*[( 1000.00**3)/( 12.00)]**.2 = 14.970 10.00 Year computed rainfall (In./Hr.) = 2.192 Decimal Fraction Soil Group A = 1.000 Decimal Fraction Soil Group B = .000 Decimal Fraction Soil Group C = .000 Decimal Fraction Soil Group D = .000 Single family(1/4 Acre lot) runoff coefficient = Runoff Index for AMC2 = 32.00 Effective Runoff Coefficient used (Q=CIA) is C = .646 Subarea runoff (CFS) = 13.89 Total area(ACRES) = 9.80 .6463 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 3.01 to Point/Station 3.02 *** CONFLUENCE OF MINOR STREAMS *** ------------------------------------------------ --------------------------- 10.00 Year computed rainfall (In./Hr.) = 2.192 ALONG THE MAIN STREAM NUMBER: 2 he flow values used for the stream: 1 are: ime of concentration(min.) T 14.97 Rainfall intensity (in./hr/) = 2.19 Total flow area (Acres) = 9.80 Total runoff (CFS) at confluence point - 13.89 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 4.01 to Point/Station 4.02 *** INITIAL AREA EVALUATION *** AsSLImmed Initial Subarea Uniform Area Type is: Single Family (1/4 Acre) TC = K*[(Length-3)/(Elevation Change)] -.2 Initial Subarea Flow Dist. = 880.00 Upstream Elevation = 76.00 Downstream Elevation = 63.00 Elevation Difference = 13.00 TC = .390*[( 880.00**3)/( 13.00)]**.2 = 13.645 10.00 Year computed rainfall (In./Hr.) = 2.314 Decimal Fraction Soil Group A = 1.000 Decimal Fraction Soil Group B = .000 Decimal Fraction Soil Group C = .000 Decimal Fraction Soil Group D = .000 W n Igle family('1/4 Acre lot) runoff coefficient unoff Index for AMC2 = 32.00 Effective Runoff Coefficient used (Q=CIA) is Subarea runoff (CFS) = 7.39 Total area(ACRES) = 4.90 C = .652 .6523 Pf VIi GDO 11 VIII iv ­11,Imo' -" - _ *** STREET FLOW TRAVEL TIME + SUBAREA FLOW ADDITION *** Upstream Elevation (Ft.) = 72.00 Downstream Elevation (Ft.) = Street Length (Ft.) = 730.00 Curb Height (In.) = 6. Street Halfwidth (Ft.) = 20.00 10istance From Crown to Crossfall Grade Break (Ft.) = 18.00 lope from Gutter to Grade Break (Ft./Ft.) = .020 Slope from Grade Break to Crown (Ft./Ft.) = .020 Number of Halfstreets Carrying Runoff = 2 Distance from curb to property line (Ft.) = 10.00 Slope from curb to property line (Ft./Ft.) = .020 Gutter width (Ft.) = 2.000 Gutter hike (distance above flow line) = 2.000 (In.) Estimated mean flow rate at MIDPOINT of street = Depth of flow = .43 (Ft.) Average Velocity = 3.41 (Ft./Sec.) Streetflow Hydraulics at MIDPOINT of street travel Halfstreet Flow Width(Ft.) = 20.00 Flow Velocity(Ft./Sec.) = 3.41 Depth*Velocity = Travel time (Min.) = 3.57 TC(min.) = 17.67 Adding Area Flow To Street 16.89 (CFS) 1.48 10.00 Year computed rainfall (In./Hr.) = 1.991 Decimal Fraction Soil Group A = 1.000 Decimal Fraction Soil Group 6 = .000 Wcimal Fraction Soil Group C = .000 cimal Fraction Soil Group D = .000 Single family(1/4 Acre lot) runoff coefficient = .6357 Runoff Index for AMC2 = 32.00 Subarea runoff = 8.73 (CFS) for 6.90 Acres Total runoff = 20.54 (CFS), Total area = 14.90 Acres Depth of flow = .46 (Ft.) Average Velocity = 3.61 (Ft./Sec.) Streetflow Hydraulics at ENDPOINT of street travel Halfstreet Flow Width(Ft.) = 20.00 Flow Velocity(Ft./Sec.) = 3.41 Depth*Velocity = 1.56 58.00 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 1.02 to Point/Station 2.01 *** CONFLUENCE OF MAIN STREAMS *** FOLLOWING DATA INSIDE MAIN STREAM ARE CALCULATED 10.00 Year computed rainfall (In./Hr.) = 1.991 The flow values used for the stream: 1 are: Time of concentration(min.) = 17.67 Rainfall intensity (in./hr/) = 1.99 41ota.l flow area (Acres) = 14.90 tal runoff (CFS) at confluence point = 20.54 Program is now starting with MAIN STREAM NO. 2 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ *** CONFLUtNUt Ur N1NUK 11KtHNJ *** Compute Various Confluenced Flow Values *** 10.00 Year 'computed rainfall (In./Hr.) = 2.314 LONG THE MAIN STREAM NUMBER: 2 The flow values used for the stream: 2 are: Time of concentrar_ion(min.) = 13.64 Rainfall intensity (in./hr/) = 2.31 Total flow area (Acres) = 4.90 Total runoff (CFS) at confluence point = 7.39 Confluence information: Stream runoff Time Intensity Number (CFS) (min.) (inch/hour) ---------------------------------------------------------- 1 13.89 14.97 2.192 2 7.39 13.64 2.314 QSMX(1) = +1.000*1.000* 13.9) + .948*1.000* 7.4) = 20.894 QSMX(2) = +1.000* .911* 13.9) +1.000*1.000* 7.4) = 20.051 Rainfall intensity and time of concentration used for 2 streams. �dividual stream flow values are: 13.89 7.39 Possible Confluenced flow values are: 20.89 20.05 Individual Stream Area values are: 9.80 4.90 Computed confluence estimates are: Runoff(CFS) = 20.89 Time(min.) Total main stream study area (Acres) 14.970 14.70 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 4.02 to Point/Station 5.01 *** STREET FLOW TRAVEL TIME + SUBAREA FLOW ADDITION *** Upstream Elevation (Ft.) = 63.00 Downstream Elevation (Ft.) = 60.00 Street Length (Ft.) = 700.00 Curb Height (In.) = 8. Street Halfwidth (Ft.) = 20.00 Distance From Crown to Crossfall Grade Break Slope from Gutter to Grade Break (Ft./Ft.) = Slope from Grade Break to Crown (Ft./Ft.) = Number of Halfstreets Carrying Runoff = 2 Distance from curb to property line (Ft.) _ Slope from curb to property line (Ft./Ft.) = utter width (Ft.) = 2.000 (Ft.) - 18.00 .020 .020 10.00 .020 Wtter hike (distance above flow line) = 2.000 (In.) Estimated mean flow rate at MIDPOINT of street = Depth of flow = .59 (Ft.) 26.44 (CFS) Streetflow Hydraulics at MIUVUtni OT sLreeL Gravel Halfstreet Flow Width(Ft.) = 20.00 Flow Velocity(Ft./Sec.) = 2.41 Depth*Velocity = 1.43 'Travel time (Min.) = 4.84 TC(min.) = 19.81 10dding Area Flow To Street 10.00 Year computed rainfall (In./Hr.) = 1.863 Decimal Fraction Soil Group A = 1.000 Decimal Fraction Soil Group B = .000 Decimal Fraction Soil Group C = .000 Decimal Fraction Soil Group D = .000 Single family(1/4 Acre lot) runoff coefficient = .6285 Runoff Index for AMC2 = 32.00 Subarea runoff = 9.14 (CFS) for 7.80 Acres Total runoff = 30.03 (CFS). Total area = 22.50 Acres Depth of flow = .62 (Ft.) Average Velocity = 2.54 (Ft./Sec.) NOTE: Depth of flow exceeds top of crown. Streetflow Hydraulics at ENDPOINT of street travel Halfstreet Flow Width(Ft.) = 20.00 Flow Velocity(Ft./Sec.) = 2.41 Depth*Velocity = 1.48 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 5.01 to Point/Station 6.01 *** STREET FLOW TRAVEL TIME + SUBAREA FLOW ADDITION *** Upstream Elevation (Ft.) 60.00 Downstream Elevation (Ft.) = 58.00 0treet Length (Ft.) = 600.00 Curb Height (In.) = 8. treet Halfwidth (Ft.) = 20.00 Distance From Crown to Crossfall Grade Break (Ft.) = 18.00 Slope from Gutter to Grade Break (Ft./Ft.) = .020 Slope from Grade Break to Crown (Ft./Ft.) = .020 Number of Halfstreets Carrying Runoff = 2 Distance from curb to property line (Ft.) = 10.00 Slope from curb to property line (Ft./Ft.) = .020 Gutter width (Ft.) = 2.000 Gutter hike (distance above flow line) = 2.000 (In.) Estimated mean flow rate at MIDPOINT of street = 32.50 (CFS) Depth of flow = .65 (Ft.) Average Velocity = 2.44 (Ft./Sec.) NOTE: Depth of flow exceeds top of crown. Streetflow Hydraulics at MIDPOINT of street travel Halfstreet Flow Width(Ft.) = 20.00 Flow Velocity(Ft./Sec.) = 2.44 Depth*Velocity = 1.59 Travel time (Min.) = 4.10 TC(min.) = 23.92 Adding Area Flow To Street a10.00 Year computed rainfall (In./Hr.) = 1.671 c.imal Fraction Soil Group A = 1.000 Decimal Fraction Soil Group B = .000 Decimal Fraction Soil Group C = .000 Decimal Fraction Soil Group D = .000 Single family(1/4 Acre lot) runoff coefficient = .6169 Runoff Index for AMC2 = 32.00 Subarea runoff = 3.81 (CFS) for 3.70 Acres Depth oT Ttow = .00 kru.) Average Velocity = 2.48 (Ft./Sec.) NOTE: Depth of flow exceeds top of crown. Streetflow Hydraulics at ENDPOINT of street travel Halfstreet Flow Width(Ft.) = 20.00 6 low Velocity(Ft./Sec.) = 2.44 Depth*Velocity = 1.61 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 5.01 to Point/Station 6.01 *** CONFLUENCE OF MAIN STREAMS *** FOLLOWING DATA INSIDE MAIN STREAM ARE CALCULATED 10.00 Year computed rainfall (In./Hr.) The flow values used for the stream: 2 Time of concentration(min.) = 23.92 Rainfall intensity (in./hr/) = 1.67 Total flow area (Acres) = 26.20 Total runoff (CFS) at confluence point = 1.671 are: Program is now starting with MAIN STREAM NO. 3 33.84 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 7.01 to Point/Station 7.02 *** INITIAL AREA EVALUATION *** • Assummed Initial Subarea Uniform Area Type is: Single Family (1/4 Acre) TC = K*[(Length"3)/(Elevation Change)] -.2 Initial Subarea Flow Dist. = 800.00 Upstream Elevation = 80.00 Downstream Elevation = 57.00 Elevation Difference = 23.00 TC = .390*[( 800.00**3)/( 23.00)]**.2 = 11.497 10.00 Year computed rainfall (In./Hr.) = 2.555 Decimal Fraction Soil Group A = 1.000 Decimal Fraction Soil Group B = .000 Decimal Fraction Soil Group C = .000 Decimal Fraction Soil Group D = .000 Single family(1/4 Acre lot) runoff coefficient = .6634 Runoff Index for AMC2 = 32.00 Effective Runoff Coefficient used (Q=CIA) is C = .663 Subarea runoff (CFS) = 11.87 Total area(ACRES) = 7.00 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 7.01 to Point/Station 7.02 *** CONFLUENCE OF MAIN STREAMS *** "A* Compute Various Confluenced Flow Values *** _ _ _------ _--- --_------_-___-_-�---_ OLLOWING DATA INSIDE MAIN STREAM ARE CALCULATED 10.00 Year computed rainfall (In./Hr.) = 2.555 The flow values used for the stream: 3 are: T;mo of rnnrantration(min.) = 11.50 Total runoff (CFS) at confluence point -= 11.87 Confluence information: Stream runoff Time Intensity Number (CFS) (min.) (inch/hour) 1 20.54 17.67 1.991 2 33.84 23.92 1.671 3 11.87 11.50 2.555 QSMX(1) = +1.000*1.000* 20.5) +1.000* .739* 33.8) + .779*1.000* 11.9) = 54.789 QSMX(2) = + .839*1.000* 20.5) +1.000*1.000* 33.8) + .654*1.000* 11.9) = 58.832 QSMX(3) = +1.000* .651* 20.5) +1.000* .481* 33.8) +1.000*1.000* 11.9) = 41.494 Rainfall intensity and time of concentration used for 3 MAIN streams. Individual stream flow values are: 20.54 33.84 11.87 Possible confluenced flow values are: 54.79 58.83 41.49 dividual Stream Area values are: 14.90 26.20 7.00 Computed confluence estimates are: - Runoff(CFS) = 58.83.: Time(min.) = 23.919 Total main stream study area (Acres) = 48.10 End of computations.. , the following figures may be used for a unit hydrograph study of the same area. TOTAL STUDY AREA(ACRES) = 48.10 AREA AVERAGED PERVIOUS AREA FRACTION(AP) _ .500 AREA AVERAGED SCS CURVE NUMBER (AMC II) = 32.0 ZO r0 am P ♦ nn n a au+♦ n PP a n J1n YI a nlnNnn nNnNnN nNN NNNN 1¢ .+.NNnnNRMN NNNN•+r � w N O WO ♦Nan an nm PO^mNn aillmmmPO^ nPYtP �n a�llNYl JI JlN J1 J�� ad as as as annnnnnnn nmm m mm mmPPPP P LL O Vi zc _ it__NNNna ams om_^-^-- cr- 4 r r ^ Om^small . . . . .eP mllln N•O NIII IR YIf • . Z� n.Y ^.-.__ _.�_ _NNNn n n a n♦ nn�nNa ♦ Y1 J1 ♦ n W^� • . r r _rrr • • _ Vcr � m W N NNr•^NN^rw Z� _Nni JI anm p orNnlYla l-mPo Nnf YlanmPo NII♦ N-0nOmOrNnf Yt: M -m W..¢_..rr..^.+^^»NrvrvNNrvNrvNNnnnnnnnnn ffffff •♦ O M 01 ... N mP o a Jla :aPNn 1: 1: a 1¢ - h N N N N N N N N n n n♦ a J1 _ � E 0 n_Nnaln-0nm Perrvn alnanmPo^N 4 r:n ren .n .n ✓•.n v+aaaaa aaa a anon V N c6 ZLL � O m E �-- c i•i= I t■ � (�j en i N „ N • C f N a n m O N a n n P N a Yl a o C L ^ W • r � L ¢ n O allf a a as an nmm m N iflm oNNP NN•m ^ Mm --yl � ^ O W ^ N N N N N N n n n n f a♦• f l a m 0 Q �a O O N O N-0 a-0-0 n A n F n n W d d g m m b m m m'm W P •O P P a P P P P O 0 o e o^ .. _ N n♦ ♦In VI -0 a C � Z .. . • . . • • • • • • • • • • . . . • . . . . . . . . . • • • • L �¢ ..»r».. .. .. .. ..rr.._rr_ it �a � o 0 J I^ N na V1 a n m Po^N n♦ If1ah m P O rNnf lfla n mP 0 ^Nnf 1i1-0nm PO ^N nfln ar-m _ _ r r r r r- r .. N N N N N N N N N N n n n n n n n n n n f a a f f f a f♦ � n W V „ C O � N V C N Z � v m = ar o¢ O n n N N O n' CL :L t ZO �q-Pa^aon.prN U)W a Ylf -0nmPXr„ ♦ O C 1 �o v o aonnnffNn^loom^ M N : ^ nnn.•mmamnm w . . . . . . . . . . . . . . . . . loW NNn^_nry W — O o N _ .2 ^ m N m m m m m-0 m N N I 1 ¢ �-^^^ ^^•_^^•r_rNNNNN NNNnn Nnnf mn-0nmm N^^ m QW M 0 Wo _ . N n f m -0h m Pe.+ f m -0n O Pe..Nnf ma nm PorNnf m-0 R C F C Ok W C D RAINFALL PATTERNS HYDROLOGY 1\/JANUAL IN PERCENT PLATE E- 5.9 HYDROGRAPH ---- Used RCFCRWCD manual plate e5. 9 for rainfall pattern 010= 58.53 per attached study INFILTRATION RATE PER LEIGHTON REPORT 11 IN/HR /1.5 SAFETY = 7.33 IN/Hh INCREMENTAL VOLUME = 3600 SECONDS/HOUR X 0 = CUBIC FEET FERC VOLUMES = 4' DIA, 30' DEEP DRY WELL RATES X 14 WELLS X (LEIGHTON RATE) 7.33 IN/HR X 390 SF= 3337 CF/HR GRASS AREA = 8910 SF X (CITY 2.00 IN/HR = 1485 CF/HR SLOPE AREA = 15500 SF X 7.33 IN/HR = 9472 CF/HR LEACH AREA = 1100 LF X 3 7.33 IN/HR = 2017 CF/HR TOTAL 16311 CF/HR * GRASS AREA = BOTTOM AREA - LEACH AREA MAX STORAGE NEEDED = 21359 CF MAX STORAGE AVAILABLE = 139321 CF HOUR % of INCREMENTAL TOTAL FERC STORAGE ..__---_-----------.-----------------------------_--___ 010 0 VOLUME VOLUME VOLUME NEEDED 1 1.2% 0.70 GFS 2528 --______---------------_----__--------- 2528 CF 2528 CF 2 1.3% 0.77 CFS 2781 5310 CF 5310 CF 3 1.8% 1.05 CFS 3793 9103 CF 9103 CF 4 2.1% 1.23 CFS 4425 1357 CF 13527 CF 5 2.3% 1.35 CFS 4846 18374 CF 18374 CF 6 2.9% 1.70 CFS 6111 24484 CF 24484 CF 7 3.8% 2.22 CFS 8007 32491 CF 32491 CF 8 4.6% 2.69 CFS 9693 42184 CF 42184 CF 9 6.3% 3.69 CFS 13275 55458 CF 55458 CF 10 8.2% 4.80 GFS 17278 72736 CF 7736 CF 968 CF 11 7.0'/. 4.10 CFS 14750 87486 CF 87486 CF 12 7.3% 4.27 CFS 15382 102868 X2868 CF 102866 12866 CF 13 10.8'/. 6.32 CFS 22756 125624 CF 125624 CF 6446 CF 14 11.4% 6. 67 CFS 24021 149645 CF 149645 CF 14156 CF 15 10.4% 6.09 CFS 21914 171558 CF 171558 CF 19759 CF 16 8.5% 4.98 CFS 1*7910 189469 CF 189469 CF 21359 CF 17 1.4% 0.82 CFS 2950 192419 CF 192419 CF 7998 CF 18 1.9% 1. 1 1 CFS 4003 196422 CF 19642 CF 19 1.3% 0.76 CFS 2739 199161 CF 199161 CF 20 1.2% 0.70 CFS 2528 201690 CF 201690 CF 21 1. 1% 0.64 CFS 2318 204007 CF 204007 CF 22 1.0% 0.59 CFS 2107 206115 CF 206115 CF 23 0. 9% 0.53 CFS 1896 2080 11 CF 2080 1 CF 24 0.8% 0.47 CFS 1686 209697 CF 209697 CF HYDROGRAPH ---- Used RCFC&WCD manual plate e5.9 for rainfall pattern 0100= 106.64 per attached study INFILTRATION RATE PER LEIGHTON REPORT 11 IN/HR /1.5 SAFETY = 7.33 IN/HR INCREMENTAL VOLUME = 3600 SECONDS/HOUR X 0 = CUBIC FEET FERC VOLUMES = 4' DIA, 30' DEEP DRY WELL RATES X 14 WELLS X (LEIGHTON RATE) 7.33 IN/HR X 390 SF= 3337 CF/HR ***GRASS AREA = 8910 SF X (CITY 2.00 IN/HR = 1485 CF/HR SLOPE AREA = 15500 SF X 7.33 IN/HR = 9472 CF/HR LEACH AREA = 1100 LF X 3 7.33 IN/HR = 2017 TOTAL 16311 CF/HR *** GRASS AREA = BOTTOM AREA - LEACH AREA MAX STORAGE NEEDED = 139213 CF MAX STORAGE AVAILABLE = 139321 CF HOUR % of INCREMENTAL TOTAL FERC STORAGE -------------------------------------------------------------------------------- 0100 0 VOLUME VOLUME VOLUME NEEDED 1 1.2% 1.28 CFS 4607 4607 CF 4607 CF 2 1.3% 1.41 CFS 5068 9674 CF 9674 CF 3 1.8% 1.92 CFS 6910 16585 CF 16585 CF 4 2.1% 2.24 CFS 8062 24647 CF 24647 CF 5 2.3% 2.45 CFS 8830 33476 CF 33476 CF 6 2.9% 3.09 CFS 11133 44610 CF 44610 CF 7 3.8% 4.05 CFS 14588 59198 CF 59198 CF 8 4.6% 4.91 CFS 17660 76858 CF 76858 CF 1349 9 6.3% 6.72 CFS 24186 101044 CF 101044 CF 9224 10 8.2% 8.74 CFS 31480 132524 CF 132524 CF 24394 it 7.0% 7.46 CFS 26873 159397 CF 159397 CF 34957 12 7.3% 7.78 CFS 28025 187422 CF 187422 CF 46671 13 10.8% 11.52 CFS 41462 228884 CF 212037 CF 71822 14 11.4% 12.16 CFS 43765 272649 CF 228348 CF 99277 15 10.4% 11.09 CFS 39926 312575 CF 244658 CF 122892 16 8.5% 9.06 CFS 32632 345206 CF 260969 CF 139213 17 1.4% 1.49 CFS 5375 350581 CF 277279 CF 128278 18 1.9% 2.03 CFS 7294 357875 CF 293590 CF 119261 19 1.3% 1.39 CFS 4991 362866 CF 309901 CF 107941 20 1.2% 1.28 CFS 4607 367473 CF 326211 CF 9638 21 1.1% 1.17 CFS 4223 371696 CF 342522 CF 84150 22 1.0% 1.07 CFS 3839 375535 CF 358832 CF 71679 23 0.9% 0.96 CFS 3455 378990 CF 375143 CF 58823 24 0.8% 0.85 CFS 3071 382061 CF 382061 CF 45584 oul J J z z 0 0 a W W cr (� a VI � l � W O M 4 V 0 Z f� LL a � 0 Lf) C) Lf) O d' ►'] to N N T T (spuosnoy_L) 1333 019f10 NI S3P4n-10A a) E 3 N u ai N CL N 4 C) N co T O (O a4r T 'O T � � J Li `7 Q acon C) (n ° �J E X LW u C LO cm &"Lq�w O w7 1 t•] JIN N T T L? r M r cn T a � 0 Lf) C) Lf) O d' ►'] to N N T T (spuosnoy_L) 1333 019f10 NI S3P4n-10A a) E 3 N u ai N CL N 4 C) N co T O (O a4r T 'O T � � J Li `7 Q acon C) (n ° �J E X LW u C LO cm &"Lq�w O w7 1 a a 0 W F- 8 Z O F— cc a F— _J Z OW � C W� 3:a0y � cr 0 o� �� •C � � _ ry l`1 O ` y. Z _ N ^ � 4 ° N c "'1 raj M NIN N N Z cc U d� y ca � � � U U> ` '° p N n M„ 3� NZ N T ti n O\ p p D O q c Qi N a C L L M LL 2 � W4 C_ ^ � 4 ° N c "'1 raj M NIN N N Z cc y ca U cn '- M„ 3� NZ N T ti n O\ p p D O q N vi ` In 1- = 0 f "e c Qi N a = /1r O •� LU c "'1 raj M NIN N N Z cc U 1 M„ E NZ ti n O\ p p D O q it c Qi N a R ■■■■■■■■■■■■■■■■■ fpm • n■® ME a M N o J •ay •u,IJ ale,u U0 11'ea} mul INFILTRATION RATE Project No Project Name • : `ri7, %40,—� CURVE Date Figure No. "TFST -'�'--Z r W C.L. LL L Ocr 1 � LLI LLJ c W �• a p s p a W � m to tin w M fn n "" N? LL L Ocr O W �• a p s p a m to tin w M fn n "" N? Z � ¢ J >cr cq a T 2 +M E 2 ` ,� r U > I T- N T 0 0 ELJ T C L O W �• a p s p a m to tin w M fn n "" N? Z � ¢ J E 2 ,� r U > I T- cq T 0 0 ELJ T C '- L O W to tin w M fn n "" N? Z ¢ I T- No 0 0 T :`Z.e• to IV RETENTION BASIN SCALE 1"-100 cn G n - W Z D `C: _ 20' EXISTING VICINITY MAP NO SCALE 60' C50)� TYPICAL SECTION - INTERIOR STREETS L _ 20 PAVEMENT MEDIAN TO BE CONSTRUCTED OR BONDED FO . W, Ly 10, R/W L.S. ESM'T 55' S'LY R/w 20 L.S. ESM TYPICAL SECTION - MILES AVENUE 44 TYPICAL SECTION - DUNE PALMS ILI n HYDROLOGY MAP TENTATIVE TRACT MAP NO. 23935 SEPTEMBER 1988 tz v1S1=D x0 --L0 - 56 GENERAL NOTES 1. GROSS ACREAGE - 50.0+ 2. NUMBER OF LOTS: 3. MINIMUM LOT SIZE - 7,200 S.F. 4. EXISTING ZONING: R-1 5. EXISTING G.P. DESIGNATION: MED. DENSITY RESIDENTIAL (4-8 U/AC) 6. EXISTING LAND USE: UNDEVELOPED DESERT 7. PROPOSED LAND USE: SINGLE FAMILY RESIDENTIAL 8. UTILITIES: SEWER AND WATER: COACHELLA VALLEY WATER DISTRICT ELECTRIC: IMPERIAL IRRIGATION DISTRICT GAS: SOUTHERN CALIFORNIA GAS COMPANY TELEPHONE: GENERAL TELEPHONE COMPANY CABLE TELEVISION: PALMER CABLEVISION 9. STORMWATER TO BE RETAINED ON-SITE. 10. LAND IS NOT SUBJECT TO OVERFLOW, INUNDATION OR FLOOD HAZARD. 11. INTERIOR STREETS TO BE DEDICATED TO PUBLIC. 12. THIS MAP INCLUDES ENTIRE CONTIGUOUS OWNERSHIP OF "LA QUINTA 47". 13. PARKWAYS ON PERIMETER STREETS AND STORMWATER RETENTION AREA TO BE PLACED IN LANDSCAPING MAINTENANCE DISTRICT. 14. MIN. DEPTH =100' MIN. WIDTH =60' (35'ON CUL -DESACS Q KNUCKLES) OWNER/DEVELOPER LA QUINTA 47 74-075 EL PASEO, NO. A4 PALM DESERT, CALIFORNIA 92260 (619) 346-6445 LEGAL DESCRIPTION NE 1/40F THE SW 1/4 AND THE NORTHERLY 330 FEET OF THE SE 1/4 OF THE SW 1/40F SECTION 20, TOWNSHIP 5 SOUTH, RANGE 7 EAST, SAN BERNARDINO BASE AND MERIDIAN. ASSESSOR PARCEL NUMBERS 613-431-007 613-431-008 STREET CAPACITY CALCULATIONS - ,9 = (/ 48 6, /n ) A R Z/a5 " FOR 40 ' r6W.6 TO CUfB , G C F ¢` FEOW TO TC A=B.leo sF, P=4/.O, ,P=O.If9,N21jj 0.,74 Amax.=(/.48(010.0/S-)x8./6 x0.94rS" = Z7S8'Z FOR 40' CURB 70 CURB, 8" [F ¢` FZOW TO TC. A= /4.96 SF, P=4/.4', R=0.J& 0,, = ( / 48610.0/S)x /4 9!o x 05/xS FOR S = O. 0040, 47mv.r. W/(,"C' F = /7.4 CFS <Vmax. W19"CF = 479 CFS Poe ,tl-ow &b TO 1, Aa IS, 1(o ) R1/0=O, 445 A8 = 24. l(a Q' -R = o. 539 /.46(o' )c /8' 0, 0,4".k 0. o&3 = 50•CO3 cFs / v.Q Co'CF Amax - 0.015 Q,nAK - l QB6x ./(ox0,539xo-0600 6b -Z7 5 FOZ6"CF pp O,o/5 } E k�pfE45/0 N coli No.I3486 n r 4 EMPnR90$ f� I TR. 23935 HYDROLOGY MAP .ENGINEERING SERVICE CORPORATION CONSULTANTS IN CIVIL ENGINEERING G LAND PLANNING 74-303 HIGHWAY 111, SUITE A �'� 1I II PALM DESERT, CA 92?60 1 (1- 1? -88 (619) 56&-5N7 R. 2240 -I y w_o. m MILES. AVENUE RETENTION BASIN SCALE I%100 w J r l31 i 10' i 20' 1 20' 1— XISTINI I PAVEMENT 1E3 I VICINITY MAP NO SCALE M -e 20' �L. 20' 10' •16') - (7') TYPICAL SECTION - INTERIOR STREETS - - 7L- -LA MEDIAN TO BE CONSTRUCTED OR BONDED FO &I TYPICAL SECTION - MILES AVENUE SLY R/W 20 L.S. ESM'T 0 TYPICAL SECTION - DUNE PALMS HYDROLOGY MAP TENTATIVE TRACT MAP N0. 23935 SEPTEMBER 1988 l -r--- o k o Y0 - 2-c' > GENERAL NOTES 1. GROSS ACREAGE - 50.0+ 2. NUMBER OF LOTS: 3. MINIMUM LOT SIZE - 7,200 S.F. 4. EXISTING ZONING: R-1 5. EXISTING G.P. DESIGNATION: MED. DENSITY RESIDENTIAL (4-8 U/AC) 6. EXISTING LAND USE: UNDEVELOPED DESERT 7. PROPOSED LAND USE: SINGLE FAMILY RESIDENTIAL 8. UTILITIES: SEWER AND WATER: COACHELLA VALLEY WATER DISTRICT ELECTRIC: IMPERIAL IRRIGATION DISTRICT GAS: SOUTHERN CALIFORNIA GAS COMPANY TELEPHONE: GENERAL TELEPHONE COMPANY CABLE TELEVISION: PALMER CABLEVISION 9. STORMWATER TO BE RETAINED ON-SITE. ' 10. LAND IS NOT SUBJECT TO OVERFLOW, INUNDATION OR FLOOD HAZARD. 11. INTERIOR STREETS TO BE DEDICATED TO PUBLIC. 12. THIS MAP INCLUDES ENTIRE CONTIGUOUS OWNERSHIP OF "LA QUINTA V-. 13. PARKWAYS ON PERIMETER STREETS AND STORMWATER RETENTION AREA TO BE PLACED IN LANDSCAPING MAINTENANCE DISTRICT. 14. MIN.DEPTH=100'MIN.WIDTH=60'(35'ONCUL - DE- SACS � KNUCKLES) E OWNER/DEVELOPER LA QUINTA 47 74-075 EL PASEO, NO. A4 PALM DESERT, CALIFORNIA 92260 (619) 346-6445 LEGAL DESCRIPTION NE 1/4 OF THE SW 1/4 AND THE NORTHERLY 330 FEET OF THE BE 1/4 OF THE SW 1/40F SECTION 20, TOWNSHIP 5 SOUTH, RANGE 7 EAST, SAN BERNARDINO BASE AND MERIDIAN. ASSESSOR PARCEL NUMBERS 613-431-007 613-431-008 STREET CAPACITY CALCULATIONS - 19 48 & 112 ALCULATIONSQ=/.4810111 )AR"'S /2 FOR 40' UyB TO CUQB , 6 C. F 0' FLOW TO TC. .4=8.16 SF, P=4/a, =O./99, Rs/'=o.,>'4 Qmaz. = i/4406/0 0/SJ x 8. /6 , 0.34 r s i11 = ?7S S1/r FOR 40, CURB TO CURB, 8" CF or' FLOW TO T.0 A- 149!0 Sr, P-4/.4', R=0.36 , R1/J 0.6/ 47," 0,r. = ( /. 48610.0/5) x 14.9!0 x 0.5/x 5 = 756 S �Z FDR s = 0.0040 , Q`E//G'CF = /74 CFS 44max. W18", -F = 47.40 ccs ����QPpFE�35lp e(1 I1 _ E H 0. > �� Y ; EMPIRES >D ( R TR. 2393 /.� �'`low HYDROLOGY MAP ENGINEERING SERVICE CORPORATION CONSULTANTS IN CIVIL ENGINEERING i LAND PLANNING 74-303 HIGHWAY 111, SUITE A _ PALM DESERT, CA 92260 1 _nn (619) 568-5997 R.0 % VO 2240-1 W.0 - fir C'O/VSTh2UGT/ON NOTES OCOn/ST,Q�-/CT �RYV✓EG-G--, ,a,F� .CDCTA/C_ SHT. / � 20' (�)C'O/V^�T,�2 tJCT CO/\.C.�E7-E b,`?/VE PER bETA/L ��JJ (�cT/ON Ccs TN/S SH T. , Cs�d/STP?CJCT /-eX/Q.'X ✓d' ��-- CO/VS T.PC/CT /2" F-L�7P�i^>T�rQTEd P/FLS /rV /2o c/� /�E•O/�//�/!� �/Z /.�"TA/L- T�/s S'HEE'T R/w ' 26.5' 61 90,5 S� ZY 41 MAX. W.5 = 57 96 W 16'X 2s HEEP SCALE III= 403/RaK U® Z06 vc loo vc ' SECTION OC:) SFECTION ti r-0KLOT 10 i N_ e EC.=52.00 20 I°J `°cl�IB 17 I(o15 14 13 12 11 10 r (0 00 EFf _ _ c• n- <:... , t. ONE_ O .D G�f t�lEY ti� o G e, o i ', � � .. _____���-,-_-_..�__----``J_—.-^•_..--�--�---------- �' -_- -\ ._----__ ---_ — _ �- ;_ :=- I� 'CUToFF WALL , T , 1 - '(p I C6 --- tr 1O.7 6..$,3 �' ' � 66.2' \._ 5A JJ / 7 . S 13 14 15 1 3 n zo I nn � rI z C -1-07H �y� �� \ /� ',i. �\ co o� I eLoL-K ALL. f ? Q F_ C"�✓CN f✓ ! \ / 1 / /� / �J 0 I " 12.11 PE�at�ATE"D - _ 15ACKFILL F1PE r / r_: OL 3 10II�N�YIy� /. DO 23� \ \ D 1� 8 8 V 6 zO I �,• // 1-.) l i J r/ / 52. a I a F / Itl Q 4 — i' �r' / `-% -�_) .i 5 rye � �i,.Y� //, / 'r '.'..+ � ,/, �••i �I \ O t- o l •1i7, <. I 6.S ---� ,...O "12.Co .....--� -�-� , 0.5. 683 2- � 62.Ls - Cy - -' • / - I . �1 �1 .. 1 1}I11 11 I,WiI -, !N_ ��+1;f11IHI IHiI 1 1lftli � I Fl I 111ilIJf I1fI11 I � � 1...� _ , w l \. Y t / ;' I ._ ; �/.... ..:._ -.�. L. � � /. -� ,; ,� -._- '- - __.�-.-...ti .� _t. �' f ; I 510 O .•10 ,' S - f III••, , � 2 r-..•`.. \ 1 - JAC zs \ LLI ^ _ r W I {� V. I I _�5 f �. t / / - -- _- •''., -f i 1 � L7 �,��' ^ ��f,; f; .... �� I / _..� •. Oreo-rEc r�1 —� �� W , r' LIJ l._...: (.'= N r_._...� / i,..`.\1,.�T�.,..%- ,' 'G "TING rcv ,, —_-. r'— ... ,__ e \ ....� ._i o� I'�4-' ... GV�iOUND ELEVATION 1 / n s / � 2 1111 -J It FG. -L5 MIN. io Q ro - E ! � I c X07 I � ¢ ma 1 'v-/ � s - — 2...-. � v —_ �; ¢�s _. - _. (� �__. • �/�—� o — a �2 — PAD ;.:- ,__.___...., _ •-. �I�g• fl 11. 111 1 1 I I ' / � SECTIO IJ AA l`>HTS 1^ y ... I / Z � 10 J t / /) _ luull 111i 1 I it IN 1 R1IN�1#11-7 .-., -- - _� i ..-.,.,,' -- / / 1 GRADING r.. / I !� P' '✓7c 'CF' - I3 IZ C3, _ O — - — - r A -0 I / / i 'o I cl .. I T�? 3� — , S ; / A r 7 .8 e No - 33486 rte, ' 1 E 67.8 a rf m ~ / / _ _ # XPIRES I SEE SHEET 3 wv sass -- k ^ \ 7 \4 � o I l REVISIONS APPROVED BY PREPARED BY IN THE CITY OF LA QUINTA SHEET aENGINEERING SERVICE CORPORATION CONSULTANTS IN CIVIL ENGIMEENING G LANG PLANNING <V�,Corz::.QT/-/E 74-303 HIGHWAY 111.SUITE A PALM DESERT. CA 922W GRADING PLAN TRACT NO 23935 2of (61915WS097 DRAWN BYE D.A.C, / MW. ENGINEER Mw. MANAGER Y J I SHEETS FRANK REYNOLDS DATE CITY ENGINEER RCE 32740 L. E. J. RCE 33486 DATE G'"E"G' W,o:'2240-I -- L.E.J