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31310J HYDROLOGY RETENTION BASIN CALCULATIONS FOR ROUGH GRADING TRACT 31310 Apnl 21, 2005 PREPARED BY: WATSON & WATSON ENGINEERING, INC. 79440 CORPORATE CENTER. DRIVE, SUITE 107 LA QUINTA, CA. 92253 (760) 771 -6237 PROJECT DESCRIPTION Tract 31310 consists of 36 lots on 12 acres at the northeast corner of Avenue 48 and Adams Street. It's a single family residential development with lots having an area of approximately 10,000 square feet. Two on -site retention basins are utilized for drainage. One is located at the northeast corner of Avenue 48 and Adams Street and the second one is within the adjoining Tract 31311. Although the two projects are separate, they are proposed to be graded and constructed at the same time. Onsite retention basin calculations have been prepared for the design of the retention basins. The westerly portion of the site (area A -1) drains to retention basin A -1. The easterly portion of the site (A -2) drains to retention basin B -1 in Tract 31311. Calculations are provided for the 3 hour, 6 hour and 24 hour 100 year storms. The Riverside County Flood Control manual is utilized for the design. DESIGN CRITERIA The design criteria utilized for this tract is consistent with that used for the Rancho La Quinta project directly south of the property fronting Avenue 48. It consists of approximately 800 acres with over a dozen residential tracts approved by the City of La Quinta and constructed. As was used in Rancho La Quinta, the 100 -year rainfall is four inches per hour. Based upon the lot sizes within the tract, the Development type is 1/4 acre. The soil for this project is consistent with that of Rancho La Quinta and therefore we used soil type "A ". The 100 year rainfall for the 3 -hour and 6 -hour 100 year storms are two inches and two and a half inches respectfully. These values are based upon judgement, utilizing plates E -5.2, E -5.4 and E -5.6 of the Riverside County Flood Control manual and previously approved criteria. Percolation tests for each of the retention basins were performed by Earth Systems Southwest and the results of the tests are included in this report. The data provided was used for the retention basin calculations. The freeboard in the basins, the elevation difference between the water surface elevation for the 100 -year storm and the lowest finish floor elevation of the project and the outlet elevation of the basins provides the factors of safety for the basin design. RETENTION BASINS Based upon the design criteria discussed above the required storage volume for the basins has been calculated. Included in this report are the volume calculations for basins B -1 and B -3 since the A -2 drainage area within this tract contributes to the volume requirements of the B -1 and B -3 basins. The retention basins are within the tract and within the fenced area of the project. Our discussions with the city regarding depth of the basins when the tentative map was being processed was that if the basins were within the fenced area of the project, that additional depth can be used for the basins. It should also be no that the city designed low point in 48" Avenue has forced the retention basins B -1 and B -3 to be much lower than would typically be required. HYDRAULIC DESIGN The Riverside County Flood Control Manual was used to Q,o and Q100 flows for catch basins and storm drains. The sizing of catch basins and storm drains is based upon Q,00 and the 100 -year water surface elevations in the basins. Calculations for each of the storm drains are included in this report. RETENTION BASIN VOLUME CALCULATIONS BASIN A -1 SUBJECT: TRACT 31310 PAGE 1 OF 1 DROJECT: JOB NO: _OCATION: BY: LWW CLIENT: DATE: HYDROGRAPH DAC RETENTION AREA TRACT 31310 USE RCFCD HYDROLOGY MANUAL PLATE E -5.9 FOR RAINFALL PATTERN. USE 100- YEAR 24 -HOUR PRECIPITATION = 4.0" DEVELOPMEN = 1%4 DRAINAGE AREA "A1" SOIL TYPE A LATE TOTAL DRAINAGE AREA = 7.52 AC (1) (2) (3) INCL. NET PERIOD RAINFALL Q VOL. PREY. ST PERC. CUM. STOR. (HOUR) % INS. (PER HR) C C.F.S. (C.F.) (C.F.) (C.F.) (C.F.) 1 1.2 0.048 0.461 0.166 599 0 533 66 2 1.3 0.052 0.462 0.181 650 716 533 183 3 1.8 0.072 0.464 0.251 904 1,088 533 555 4 2.1 0.084 0.467 0.295 1,062 1,617 533 1,084 5 2.8 0.112 0.470 0.396 1,425 2,509 533 1,976 6 2.9 0.116 0.471 0.411 1,479 3,455 533 2,922 7 3.8 0.152 0.478 0.546 1,967 4,889 533 4,356 8 4.6 0.184 0.483 0.668 2,406 6,762 636 6,126 9 6.3 0.252 0.491 0.930 3,350 9,476 636 8,840 10 8.2 0.328 0.501 1.236 4,449 13,288 636 12,652 11 7.0 0.280 0.497 1.046 3,767 16,420 741 15,679 12 7.3 0.292 0.498 1.094 3,937 19,615 741 18,874 13 10.8 0.432 0.516 1.676 6,035 24,909 847 24,062 14 11.4 0.456 0.518 1.776 6,395 30,457 847 29,610 15 10.4 0.416 0.513 1.605 5,777 35,387 967 34,420 16 8.5 0.340 0.503 1.286 4,630 39,050 967 38,083 17 1.4 0.056 0.465 0.196 7,058 38,788 967 37,821 18 1.9 0.076 0.466 0.266 959 38,780 967 37,813 19 1.3 0.052 0.462 0.181 650 38,463 967 37,496 20 1.2 0.048 0.461 0.166 599 38,095 967 37,128 21 1.1 0.044 0.460 0.152 548 37,676 967 36,709 22 1.0 0.040 0.459 0.138 497 37,206 967 36.239 23 0.9 0.036 0.458 0.124 446 36,685 967 3`5,718 24 0.8 0.032 0.458 0.110 397 36,115 967 35,148 R (1) RAINFALL = % OF TOTAL PERCIPITATION A = 7.52,A" SOIL WPE "A" (2) Q= RAINFALL x C x A (INS. PER HOUR) C = ,S NGLE FAMILY 1/4 AC (3) V = Q x 3600 = c.f. / HR (4) PERC RATE = 1.1" PER HOUR = .092' PER HOUR G: /Administration /COST ESTIMATES /HYDROGRAPH.wb3 SUBJECT: TRACT 31310 PAGE 1 OF 1 "ROJECT: JOB NO: .00ATION: BY: LWW CLIENT: DATE: HYDROGRAPH RETENTION AREA TRACT 31310 USE RCFCD HYDROLOGY MANUAL PLATE E -5.9 FOR RAINFALL PATTERN. USE 100- YEAR 3 -HOUR PRECIPITATION = 2.2 DEVELOPMENT = 1/4 AC DRAINAGE AREA "A1" SOIL TYPE A (PLATE D -5.1) TOTAL DRAINAGE AREA = 7.52 AC (1) RAINFALL = % OF TOTAL PERCIPITATION A = (2) Q= RAINFALL x C x A (INS. PER HOUR) C = (3) V = Q x 3600 = c.f. / HR _7.52 ACRE SOIL TYPE "A" COEFF. FOR SGL FAM 1/4 AC LOT (4) PERC RATE = 1.1" PER HOUR = .092' PER HOUR (FROM PLATE E-6.2) G: /Administration /COST ESTIMATES /HYDROGRAPH.wb3 (1) (2) (3) INCL. NET PERIOD RAINFALL Q VOL. PREV. ST PERC. CUM. STOR. _(HOUR) % INS. (PER HR) C C.F.S. (C.F.) (C.F.) (C.F.) (C.F.) 1 3.7 0.081 0.466 0.284 1,023 1,023 133 890 2 4.8 0.106 0.468 0.373 1,343 2,233 133 2,100 3 5.1 0.112 0.470 0.396 1,426 3,526 133 3,393 4 4.9 0.108 0.468 0.380 1,368 4,761 133 4,628 5 6.6 0.145 0.473 0.516 .1,858 6,486 159 6,327 6 7.3 0.161 0.474 0.574 2,066 8,393 - 159 8,234 7 8.4 0.185 0.480 0.668 2,405 10,639 159 10,480 8 9.0 0.198 0.482 0.718 2,585 13,065 159 12,906 9 12.3 0.271 0.491 1.001 3,604 16,510 185 16,325 10 17.6 0.387 0.505 1.470 5,292 21,617 185 21,432 11 16.1 0.354 0.503 1.339 6,008 27,440 211 27,229 12 4.2 0.092 0.467 0.323 1,163 28,392 211 28,181 (1) RAINFALL = % OF TOTAL PERCIPITATION A = (2) Q= RAINFALL x C x A (INS. PER HOUR) C = (3) V = Q x 3600 = c.f. / HR _7.52 ACRE SOIL TYPE "A" COEFF. FOR SGL FAM 1/4 AC LOT (4) PERC RATE = 1.1" PER HOUR = .092' PER HOUR (FROM PLATE E-6.2) G: /Administration /COST ESTIMATES /HYDROGRAPH.wb3 SUBJECT: TRACT 31310 PAGE 1 OF 1 PROJECT: JOB NO: LOCATION: BY: LWW CLIENT: DATE: HYDROGRAPH RETENTION AREA TRACT 31310 USE RCFCD HYDROLOGY MANUAL PLATE E -5.9 FOR RAINFALL PATTERN. USE 100- YEAR 6 -HOUR PRECIPITATION = 2.5" DEVELOPMENT = 1/4 AC DRAINAGE AREA "Al" SOIL TYPE A (PLATE D-5.1) TOTAL DRAINAGE AREA = 7.52 AC (1) (2). (3) INCL. NET PERIOD RAINFALL Q VOL. PREY. ST PERC. CUM. STOR. HOUR) % INS. (PER HR) C C.F.S. (C.F.) (C.F.) (C.F.) (C.F.) 1 1.7 0.043 0.460 0.149 536 563 133 403 2 1.9 0.048 0.461 0.166 598 1,004 133 868 3 2.1 0.053 0.462 0.184 662 1,533 133 1,397 4 2.2 0.055 0.462 0.191 688 2,088 133 1,952 5 2.4 0.060 0.463 0.209 752 2,707 133 2,571 6 2.4 0.060 0.463 0.209 752 3,326 133 3,190 7 2.4 0.060 0.463 0.209 752 3,945 133 3,809 8 2.5 0.063 0.463 0.219 788 4,600 133 4,464 9 2.6 0.065 0.464 0.227 817 5,284 133 5,148 10 2.7 0.068 0.464 0.237 853 6,004 133 5,868 11 2.8 0.070 0.464 0.244 878 6,749 159 6,587 12 3.0 0.075 0.465 0.262 943 7,533 159 7,371 13 3.2 0.080 0.466 0.280 1,008 8,382 159 8,220 14 3.6 0.090 0.468 0.317 1,141 9,364 159 9,202 15 4.3 0.108 0.481 0.391 1,408 7,797 159 10,451 16 4.7 0.118 0.482 0.428 1,541 9,179 159 11,833 17 5.4 0.135 0.483 0.490 1,764 10,784 159 13,438 18 6.2 0.155 0.484 0.564 2,030 12,655 159 15,309 19 6.9 0.173 0.484 0.630 2,268 14,764 185 17,392 20 7.5 0.183 0.485' 0.667 2,401 16,980 185 19,608 21 10.6 0.269 0.492 0.995 3,582 20,377 185 23,005 22 14.5 0.363 0.506 1.381 4,972 25,164 211 27,766 23 3.4 0.085 0.467 0.299 1,076 26,029 211 28,631 24 1.0 0.025 0.456 0.086 310 26,128 211 28,730 (1) RAINFALL = % OF TOTAL PERCIPITATION A'= (2) Q= RAINFALL x C x A (INS. PER HOUR) C = (3) V = Q x 3600 = c.f. / HR 7.52 ACRE SOIL TYPE "A" COEFF. FOR SGL FAM 1/4 AC LOT (4) PERC RATE = 1.1" PER HOUR = .092' PER HOUR (FROM PLATE E-6.2) G: /Administration /COST ESTIMATES/HYDROGRAPH.wb3 f (c+) la,.i.'.'C bV.LE = .a'.1,. bEY I. -IO 16 = kb—,S, bEV HC,MS (EVOI ; brVi.r Efe•-) (:�)A- 0,t20- 00 =C *V\IHLS (114.3' bsK Hof fu) ES) o= b t-- „�vrr x C x v Of_S V fbihCi:.'a VFV NJ CCir .l.n" Ev (br,%- E 1:i'2'yi nSE 400- AEdI� 1)-Hof { 1�iJw_l�.fi'! LY.:, IMI = Y% DENFt-0 1, -�EEVI ra 4104 VC nee &C�-CD HADIS01 -00A Vf,:'iAnvr i -)r i.0 �F� Ft?f3 bvil/iL ' r by .LEfac1w CiiF111 Ki—:1FiWO11 'Vq1E:vw' ttACi 34340 HA PjBCC,t&VbH LOk. 108 viol, t*/3E 1 �i o tw t ct�fr .1.�.t3ir � t U u4fi: t:f iE 5qt 4'0 0 !32 01420, 6-000 314 5C-'JS9 51: 53':3(1 344 Se`E34 SS 444”' T2c-1 0`-)OR 3'394 q'ims 52'42,t 5J1 5112e v f J0'L -' 0'5'33 0 �tit5 U'ti�; 3`1$5 3J 31:. 4 $2 S3'i?02 S0 s'2 C':83 3'Q82. G'2e1 S'a0J 10'd80 482 J�'130�3 Jaa e'a U'J13 t)IR4 0£120 S'S68 1ti'1 4P? 41'3335 43 M's O'J?e 0.133 0.021 s 030 45-eek aka 48.30a 41 2 , 0's8 -t 42B 4.3'131 ie d'`_, 0.448 01cS 0'11u9 432.1' v't.Sa i2 F1 4J'ea: 1;. -fa J 40 0 .194 a 3• °.1 4 "t03 Y01 ;PC 40 IM Jv 3'8 0'080 0'1P8 0'341 1'4-44 8`3fcV 4r8 8'505 r' 3 3 "5 0'090 0,188 0 590 4'009 ?'3E5 J ?8 $ 1750 45 3'0 0,01? 0','e? 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LY.:, IMI = Y% DENFt-0 1, -�EEVI ra 4104 VC nee &C�-CD HADIS01 -00A Vf,:'iAnvr i -)r i.0 �F� Ft?f3 bvil/iL ' r by .LEfac1w CiiF111 Ki—:1FiWO11 'Vq1E:vw' ttACi 34340 HA PjBCC,t&VbH LOk. 108 viol, t*/3E 1 �i RETENTION BASIN VOLUMES BASIN Al VOLUME ELEV AREA VOLUME 50 5796 6351 51 6905 7478 52 8050 8650 53 9250 9878 54 10,506 11,162 55 11,817 VOLUME. REQUIRED.: 38,083. 100 YEAR WATER SURFACE ELEV: 54.51 ACCUMLATIVE VOLUME 6351 13,829 22,479 32,357 43,519.. . JI, RE'T'ENTION BASIN VOLUME CALCULATIONS BASIN B -1 & B3 SUBJECT: TRACT 31311 PAGE 1 OF 1 3ROJECT: JOB NO: _OCATION: BY: LWW - LIENT: DATE: HYDROGRAPH RETENTION-AREA _TRACT 31311- USE RCFCD HYDROLOGY MANUAL PLATE E -5.9 FOR RAINFALL PATTERN. USE 100- YEAR 24 -HOUR PRECIPITATION = 4.0" DEVELOPMENT = 1/4 AC DRAINAGE AREA "A2" SOIL TYPE A (PLATE D -5.1) TOTAL DRAINAGE AREA = 3.96 AC (1) RAINFALL = % OF TOTAL PERCIPITATION (2) Q= RAINFALL x C x A (INS. PER HOUR) (3) V = Q x 3600 =. c.f. / HR (4) PERC RATE = 2" PER HOUR = .167' PER HOUR G: /Administration /COST ESTIMATES /HYDROGRAPH.wb3 A = 3.96 . ACRE SOIL TYPE "A" C = . SINGLE FAMILY 1/4 AC (1) (2) (3) INCL. NET PERIOD RAINFALL Q VOL. PREV. ST PERC. CUM. STOR. 60 MIN % INS. (PER HR) C C.F.S. (C.F.) (C.F.) (C.F.) (C.F.) 1 1.2 0.048. 0.461 0.088 315 2 1.3 0.052 0.462 0.095 342 3 1.8 0.072 0.464 0.132 476 4 2.1 0.084 0.467 0.155. 559 5 2.8 0.112 0.470 0.208 750 6 2.9 0.116 0.471 0.216, 779 7 3.8 0.152 0.478.: 0.288 1,036 8 4.6' 0.184 0.483 0.352_ 1,267' 9 6.3 0.252 0.491 0.490 1,764 10 8.2 0.328 0.501 0.651 2,343. 11 7.0 0.280 0.497 0.551 1,984 12 7.3 0.292 0.498` 0.576 2,073: 13 10.8 0.432 0.516: 0.883 3,178 14 11.4 0.456 0.518` 0.935. 3,367 15 10.4 0.416 0.513 0.845 3,042 16 8.5 0.340 0.503- 0.677 2,438 17 1.4 0.056 0.465 0.103 371 18 1.9. 0.076 0.466 0.140 505 19 1.3 0.052 0.462 0.095 342 20 1.2 0.048 0.461 0.088 315 21 1.1 0.044 0.460 0.080 289 22 1.0 0.040 0.459 0.073 262 23 0.9 0.036 0.458 0.065 235 24 0.8 0.032 0.458 0.058 209 (1) RAINFALL = % OF TOTAL PERCIPITATION (2) Q= RAINFALL x C x A (INS. PER HOUR) (3) V = Q x 3600 =. c.f. / HR (4) PERC RATE = 2" PER HOUR = .167' PER HOUR G: /Administration /COST ESTIMATES /HYDROGRAPH.wb3 A = 3.96 . ACRE SOIL TYPE "A" C = . SINGLE FAMILY 1/4 AC WBJECT: TRACT 31311 PAGE 1 OF 1' )ROJECT: JOB NO: _OCATION: BY: LVWV ',LIENT:. DATE: HYDROGRAPH RETENTION AREA _ .TRACT 31.311 USE RCFCD HYDROLOGY MANUAL PLATE E -5.9 FOR RAINFALL PATTERN. USE 100- YEAR 24 -HOUR PRECIPITATION = 4" DEVELOPMENT = 60% Imp DRAINAGE AREA "B1" SOIL TYPE A (PLATE D -5.1) TOTAL DRAINAGE AREA = 13.02 AC PERIOD 60 MIN % (1) RAINFALL INS. (PER HR) C (2) Q C.F.S. (3) INCL. NET VOL. PREY. ST PERC. CUM. STOR. (C.F.) (C.F.) (C.F.) (C.F.) 1 1.2 . 0.048 0.531 0.332 1,195 2 1.3 0.052 0.532 0,360 1,297 3 1.8 0.072 0.534- 0.501- 1,802 -'-' 4 2.1 0.084 0.535 0.585 2,106 5 2.8 0.112 0.536 0.782 2,814 6 2.9 0.116 0.537 0.811 2,920: 7 3.8 0.152 0.541 1.071 3,854. 8 4.6. 0.184 0.544. 1.301 4,692': 9 6.3 0.252 0.550. 1.805 6,496 10 8.2 0.328 0.558 2.383 8,579.:.. 11 7.0 0.280 0.553 2.016. 7,258. 12 7.3 0.292 0.554 2.106 7,582' 13 10.8 0.432 0.565 3.178: 11,441 14 11.4 0.456' 0.567' 3.366• 12,119" 15' 10.4 0.416' 0.563 3.049 10,978 16 8.5 0.340 0.559 2.475 8,908 17 1.4 0.056 0.532 0.388 1,396 18 1.9 0.076 0.535 0.529 1,906 19 1.3 0.052 0.532 0.360 1,297 20 1.2 0.048 0.531 0.332 1,195 21 1.1 0.044 0.530 0.304 1,093 22 1.0 0.040 0.529 0.276 992 23 0.9 0.036 0.528 0.247 891 24 0.8 0.032 0.527 0.220 790 (1) RAINFALL = % OF TOTAL PERCIPITATION A = 13.02 ACRE SOIL TYPE "A" (2) Q= RAINFALL x C x A (INS. PER HOUR) C = COEFF. FOR 60% IMP (3) V = Q x 3600 = c.f. / HR (4) PERC RATE = B1 = 2" PER HOUR = .167' PER HOUR G: /Administration /COST ESTIMATES /HYDROGRAPH.wb3 SUBJECT: TRACT 31311 PAGE 1 OF 1 PROJECT: JOB NO: LOCATION: BY: LWW CLIENT: DATE: HYDROGRAPH RETENTION AREA TRACT 31311 USE RCFCD HYDROLOGY MANUAL PLATE E -5.9 FOR RAINFALL PATTERN. USE 100- YEAR 24 -HOUR PRECIPITATION = 4" DEVELOPMENT = 60% Imp DRAINAGE AREA "133" SOIL TYPE A (PLATE D -5.1) TOTAL DRAINAGE AREA = 6.72 AC (1) (2) (3) INCL. NET PERIOD RAINFALL Q VOL. PREY. ST PERC. CUM. STOR. . 60 MIN % INS. (PER HR) C C.F.S. (C.F.) (C.F.) (C.F.) (C. F.) 0.534 0.258" 930- 4 2.1 1 1.2 0.048 0.531 0.171 617 2 1.3 0.052 0.532 0.186 669 3 1.8 0.072 0.534 0.258" 930- 4 2.1 0.084 0.535 0.302 1,087 5 2.8 0.112 0.536 0.403 1,452 6 2.9 0.116 0.537 0.419 1,507 7 3.8 0.152 0.541 0.553 1,989 8 4.6 0.184 0.544 0.673 2,422 9 6.3 0.252 0.550 0.931 3,353 10 8.2 0.328 0.558 1.230 4,428 11 7.0 0.280 0.553 1.041 3,746 12 7.3 0.292 0.554 1.087 3,913 13 10.8 0.432 0.565 1.640 5,905. 14 11.4 0.456 0.567' 1.737 6,255 15. 10.4 0.416 0.563 1.574 5,666 16 8.5 0.340 0.559 1.277 4,598. 17 1.4 0.056 0.532 0.200 721 18 1.9 0.076 0.535 0.273 984 19 1.3 0.052 0.532 .0.186 669 20 1.2 0.048 0.531 0.171 617' 21 1.1 0.044 0.530 0.157 564 22 .1.0 0.040 0.529 0.142 512 23 0.9 0.036 0.528 0.128 460 24 0.8 0.032 0.527 0.113 408 (1) RAINFALL = % OF TOTAL PERCIPITATION (2) Q= RAINFALL x C x A (INS. PER HOUR) (3) V'= Q x 3600 = c.f. / HR A = 6.72 ACRE SOIL TYPE "A" C = COEFF. FOR 60% IMP (4) PERC RATE = B3 =.9" PER HOUR = .075' PER HOUR G: /Administration /COST ESTIMATES /HYDROGRAPH.wb3 f r" TOTAL VOL INCL. NET PERIOD REQ PREY. STOR. PERC. CUM. STOR. (A2, B1, 63) (C.F.) (C. F.) (C.F.) 1 2,127 2,127 707 1,420 2 2,308 3,728 707 3,021 3 3,208 6,229 1,413 4,816 4 3,752 8,568. 1,413 5 5,016 12,171 1,413 10,758 6 5,206 15,964 1,413 14,551 7 6,879 21,430 1,690 19,740 8 8,381 28,121 1,690 26,431 9 11,613 38,044 1,986 36,058 10 15,350 51,408 1,986 49,422 11 12,988 62,410 2,270 60,140 12 13,568 73,708 2,591 71,117 13 20,524 91,641 2,591 89,050 14 21,741 110,791 2,947 107,844 15 19,686 127,530 . 3,276 124,254 16 15,944. .140,198 ._ 3,276 136,922 �- 17 2,488 139,410 3,276 136,134 18 3,395 139,529 3,276 136,253 19 2,308 138,561 3,276 135,285 20 2,127 137,412 3,276 134,136 21 1,946 136,082 3,276 132,806 22 1,766 134,572 3,276 131,296 23 1,586 132,882 3,276 129,606 24 1,407 131,013 3,276 127,737 G: /Administration /COST ESTIMATES /HYDROGRAPH.wb3 BASIN B1 VOLUME ELEV AREA VOLUME TOTAL VOL 42.00 0.00 2,888 43.00 5,776 2,888 6,360 44.00 6,944 9,248 7,552 45.00 8,160 16,800 8,768 46.00 9,376 25,568 10,048 47.00 10,720 35,616 11,448 48.00 12,176 47,064 12,856 49.00 13,536 59,920 14,368 50.00 15,200 74,288 G: /Administration /COST ESTIMATES /HYDROGRAPH.wb3 G: /Administration /COST ESTIMATES /HYDROGRAPH.wb3 r'P BASIN B3 VOLUME ELEV AREA VOLUME TOTAL VOL 42.00 0.00 2,996 43.00 5,776 2,996 6,528 . __ - - - - - ------------ _._...------ - - - - -- - -_ -_ 44.00 6,944 9,524 7,688 45.00 8,160 17,212 8,848 46.00 9,376 26,060 10,032 47.00 10,720 36,092 11,424 48.00 12,176 47,516. 12,856 49.00 13,536 60,372 14,296 50.00 15,200 74,668 15,728 51.00 16,400 90,396 G: /Administration /COST ESTIMATES /HYDROGRAPH.wb3 VOLUME OF BASINS B1 & B3 42.00 0 43.00 5,884 44.00 18,768 45.00 34,008 46.00 51,624 47.00 71,704 48.00 94,576 49.00 120,288 50.00 148,952 VOLUME REQUIRED: 136,253 100 YEAR WATER SURFACE ELEV; 49.58 ;UBJECT: TRACT 31311 PAGE 1 OF 1 3ROJECT: JOB NO: - OCATION: BY: LWW :LIENT: DATE: HYDROGRAPH RETENTION AREA TRACT 31311 USE RCFCD HYDROLOGY MANUAL PLATE E -5.9 FOR RAINFALL PATTERN. USE 100- YEAR 3 -HOUR PRECIPITATION = 2.2" DEVELOPMENT = 1/4 AC DRAINAGE AREA "A2" SOIL TYPE A (PLATE D -5.1) TOTAL DRAINAGE AREA = 3.96 AC (1) RAINFALL = % OF TOTAL PERCIPITATION (2) Q= RAINFALL x C x A (INS. PER HOUR) (3) V = Q x 3600 = .c.f. / HR A = _3.96--ACRE SOIL TYPE "A" C = COEFF. FOR SGL FAM 1/4 AC LOT (4) PERC RATE = 2" PER HOUR = .167' PER HOUR (FROM PLATE E-6.2) G: /Administration/COST ESTIMATES/HYDROGRAPH.wb3 (1) (2) (3) INCL. NET PERIOD RAINFALL Q VOL. PREY. ST PERC. CUM. STOR. (HOUR) % INS. (PER HR) C C.F.S. (C.F.) (C.F.) (C.F.) (C.F.) 1 3.7 0.081 0.466 0.149 536 2 4.8 0.106 0.468 0.196 707 3 5.1 0.112" 0.470 0.208 - 750" 4 4.9 0..108 0.468 0.200 721 5 6.6 0.145 0.473 0.272 978 6 7.3 0.161, 0.474 0.302 1,088 7 8.4 0.185 0.480. 0.352 1,266 8 9.0 0.198 0.482 0.378:, 1,361: 9 12.3 0.271 0.491 0.527` 1,897° 10 17.6 0.387 0.505 0.774 2,786: 11 16.1 0.354 0.503.. 0.705 12 4.2 0.092 0.467 0.170: 612" (1) RAINFALL = % OF TOTAL PERCIPITATION (2) Q= RAINFALL x C x A (INS. PER HOUR) (3) V = Q x 3600 = .c.f. / HR A = _3.96--ACRE SOIL TYPE "A" C = COEFF. FOR SGL FAM 1/4 AC LOT (4) PERC RATE = 2" PER HOUR = .167' PER HOUR (FROM PLATE E-6.2) G: /Administration/COST ESTIMATES/HYDROGRAPH.wb3 SUBJECT: TRACT 31311 PAGE 1 OF 1 PROJECT: JOB NO: LOCATION: BY: WW CLIENT: DATE: HYDROGRAPH — RETENTION AREA TRACT 31311 USE RCFCD HYDROLOGY MANUAL PLATE E -5.9 FOR RAINFALL PATTERN. USE 100- YEAR 3 -HOUR PRECIPITATION = 2.2 DEVELOPMENT = 60% IMP DRAINAGE AREA "B1" SOIL TYPE A (PLATE D -5.1) TOTAL DRAINAGE AREA = 13.02 AC (1) (2) (3) INCL. NET PERIOD RAINFALL Q VOL. PREV. ST PERC. CUM. STOR. (HOUR) % INS. (PER HR) C C.F.S. (C.F.) (C.F.) (C.F.) (C.F.) 1 3.7 0.081 0.593 0.625 2,250 2 4.8- 0.106 0.595 0.821- 2,956 . 3 5.1 0.112 0.596 0.869 3,128 4 4.9 0.108 0.595 0.837 3,013 5 6.6 0.145 0.600 1.133' 4,0791 6 7.3 0.161 0.602 1.262' 4,543: 7 8.4 0.185 0.603 1.452 5,227 8 9.0 0.198 0.604. 1.557' 5,605.: 9 12.3 0.271. 0.612` 2.159- 7,772° 10 17.6 0.387 0.621 3.129:. 11,264:, 11 16.1 0.354 0.619 2.8531. 10,274:: 12 4.2 0.092 0.594 0.712' 2,563,: (1) RAINFALL = % OF TOTAL PERCIPITATION (2) Q= RAINFALL x C x A (INS. PER HOUR) (3) V = Q x 3600 = c.f. / HR A = _ 13.02 ACRE SOIL TYPE "A" C = COEFF. FOR 60% IMP (4) PERC RATE =.2" PER HOUR = .167' PER HOUR (FROM PLATE E-6.2) G: /Administration /COST ESTIMATES /HYDROGRAPH.wb3 SUBJECT: TRACT 31311 PAGE 1 OF 1 2ROJECT: JOB NO: _OCATION: BY: LWW ::DENT: DATE: HYDROGRAPH RETENTION AREA TRACT 31311 - -�- - - USE RCFCD HYDROLOGY MANUAL PLATE E -5.9 FOR RAINFALL PATTERN. USE 100- YEAR 3 -HOUR PRECIPITATION = 2.2" DEVELOPMENT = 60% IMP DRAINAGE AREA "133" SOIL. TYPE A (PLATE D -5.1) TOTAL DRAINAGE AREA = 6.72 AC (1) RAINFALL = % OF TOTAL PERCIPITATION A = 6:72 ACRE SOIL TYPE "A" (2) Q= RAINFALL x C x A (INS. PER HOUR) C = COEFF. FOR 60% IMP (3) V Q x 3600= c.f. / HR (4) PERC RATE = .9" PER HOUR = .075' PER HOUR (FROM- PLATE E-6:2) G:/Adminishabon/COST ESTIMATES /HYDROGRAPH.wb3 (1) (2) (3) INCL. NET PERIOD RAINFALL Q VOL. PREY. ST PERC. CUM. STOR. (15 min) % INS. (PER HR) C C.F.S. (C.F.) (C.F.) (C.F.) (C.F.) 1 3.7 0.081 0.593 0.323 1,162 2 4.8 0.106 0.595 0.424 1,526 3 5.1 0.112 0.596 0.449 1,615 4 4.9 0.108 0.595 0.432 1,555 5 6.6 0.145 0.600 0.585 2,105 6 7.3 0.161 0.602 0:651. 2,345 7 8.4 0.185 0.603 0.750:i 2,699 8 9.0 0.198:t 0.604 0.804: 2,893 9 12.3 0.271 0.612 1.115, 4,012. 10 17.6 0.387 0.621 1.615 5,814'• 11. 16.1 0.354 0.619 1.473 5,301: 12 4.2 0.092 0.594 0.367 1,322 (1) RAINFALL = % OF TOTAL PERCIPITATION A = 6:72 ACRE SOIL TYPE "A" (2) Q= RAINFALL x C x A (INS. PER HOUR) C = COEFF. FOR 60% IMP (3) V Q x 3600= c.f. / HR (4) PERC RATE = .9" PER HOUR = .075' PER HOUR (FROM- PLATE E-6:2) G:/Adminishabon/COST ESTIMATES /HYDROGRAPH.wb3 3 HOUR G: /Administration /COST ESTIMATES /HYDROGRAPH.wb3 TOTAL VOL INCL. NET PERIOD REQ PREY. STOR. PERC. CUM. $TOR. (A2, 131, 133) (C.F.) (C.F.) (C.F.) 1 3,948 3,948 177 3,771 2 5,189 8,960 353 8,607 3 5,493 14,100 353 13,747 4 5,289 19,036 423 18,613 5 7,162 25,775 423 25,352 6 7,976 33,328 497 32,831 7 9,192 42,023 497 41,526 8 9,859 51,385 497 50,888 9 13,681 64,569 568 64,000 10 19,864 83,864 648 83,216 11 14,134 97,350 648 96,702 12 4,497 101,199 737 100,462 G: /Administration /COST ESTIMATES /HYDROGRAPH.wb3 SUBJECT: TRACT 31311 PAGE 1 OF 1 PROJECT: JOB NO: LOCATION: BY: LWW CLIENT: DATE: HYDROGRAPH RETENTION AREA TRACT 3131-1 USE RCFCD HYDROLOGY MANUAL PLATE E -5.9 FOR RAINFALL. PATTERN. USE 100- YEAR 6 -HOUR PRECIPITATION = 2.5" DEVELOPMENT = 1/4 AC DRAINAGE AREA "A2" SOIL TYPE A (PLATE D -5.1) TOTAL DRAINAGE AREA = 3.96 AC (1) (2) (3) INCL. NET PERIOD RAINFALL Q VOL. PREY. ST PERC. CUM. STOR. (HOUR) % INS. (PER HR) C C.F.S. (C.F.) (C.F.) (C.F.) (C.F.) 1 1.7 0.043 0.460 0.078 281 2 1.9 0.048 0.461 0.088 315 3 2.1 0.053 0.462- 0.097 349 - 4 2.2 0.055 0.462 0.101. 362 5 2.4 0.060 0.463 0.110 396 6 2.4 0.060: 0.463, 0.110 396' 7 2.4 0.060: 0.463' 0.110' 396' 8 2.5 - 0.061 0.463 0.116 416 9 2.6 0.065= 0.464 0.119l° 430, 10 2.7 0.068' 0.464x • 0.125= . 450;. 11 2.8 0.070- 0.464" 0.129- 463, 12 3.0 0.075: 0.465:.. 0.138:. 497' 13 3.2 0.080:: 0.466' 0.1481 5311. 14 3.6 0.090 0.468: 0.167' 600: 15 4.3 0.108" 0.481` 0.206`- 741" 16 4.7 0.118 0.482?' 0.225 811'' 17 5.4 0.135 0.483 0.258, 930. 18 6.2 0.155 0.484' 0.297, 1,069 19 6.9 0.173 0.484 0.332 1,194 20 7.5 0.183 0.485 0.351 1,265 21 10.6 0.269_ 0.492 0.524 1,887 22 14.5 0.363 0.506 0.727 2,619 23 3.4 0.085 0.467 0.157 566 24 1.0 0.025 0.456 0.045 163 (1) RAINFALL = % OF TOTAL PERCIPITATION A = (2) Q= RAINFALL x C x A (INS. PER HOUR) C = (3) V = Q x 3600 = c.f. / HR 196 _ ACRE SOIL TYPE "A" COEFF. FOR SGL FAM 1/4 AC LOT (4) PERC RATE = 2" PER HOUR = .167' PER HOUR (FROM PLATE E-6.2) G: /Administration /COST ESTIMATES /HYDROGRAPH.wb3 SUBJECT: TRACT 31311 PAGE 1.OF 1 PROJECT: JOB NO: LOCATION: BY: LWW CLIENT: DATE: HYDROGRAPH RETENTION AREA TRACT 31311 USE RCFCD HYDROLOGY MANUAL PLATE E -5.9 FOR RAINFALL PATTERN. USE 100- YEAR 6-HOUR PRECIPITATION = 2.50" DEVELOPMENT = 60% IMP DRAINAGE AREA "81 " SOIL TYPE A (PLATE D -5.1) TOTAL DRAINAGE AREA = 13.02 AC (1) (2) (3) INCL. NET PERIOD RAINFALL Q VOL. PREY. ST PERC. CUM. STOR. (HOUR) % INS. (PER HR) C C.F.S. (C.F.) (C.F.) (C.F.) (C.F.) 1 1.7 0.043 0.589 0.330 1,188 2 1.9 0.048 0.590 0.369 1,328 3 2.1 0.053--- 0.591- 0.408- 1,469 -- 4 2.2 0.055 0.591 0.423 1,523 5 2.4 0.060 0.592 0.462 1,663 6 2.4 0.060 0.592 0.462 1,663 7 2.4 0.060 0.592 0.462 1,663' 8 2.5 0.063 0.592. 0.486• 1,750, 9 2.6 0.065 0.593' 0.502' 1,807:'l 10 2.7 0.068 0.593: 0.525; 1,8901. 11 2.8 0.070- 0.5931 0.540; 1,944'.: 12 3.0 0.075` 0.594: 0.580: 2,0881. 13 3.2 0.080 0.594" 0.619k 2,22& ' 14 3.6 0.090 0.595 0.697 2,509., 15 4.3 0.108:-, 0.596; 0.838: 3,01T. 16 4.7 0.118 0.597 0.917 3,301 17 5.4 0.135 0.601 1.056 3,802 18 6.2 0.155 0.602 1.215 4,374: 19 6.9 0.173 0.603 1.358 4,889 20 7.5 0.183 0.604 1.439 5,180 21 10.6 0.269 0.613 2.115 7,614 22 14.5 0.363 0.621 2.935 10,566 23 3.4 0.085 0.594 0.657 2,365 24 1.0 0.025 0.585 0.190 684 (1) RAINFALL = % OF TOTAL PERCIPITATION (2) Q= RAINFALL x C x A (INS. PER HOUR) (3) V = Q x 3600 = c.f. / HR A = 13.02: ACRE SOIL TYPE "A" C = COEFF. FOR-:60% IMP (4) PERC RATE =.2" PER HOUR = .167' PER HOUR (FROM PLATE E-6.2) G : /Adminis"ton/COST ESTIMATES/HYDROGRAPH.wb3 SUBJECT: TRACT 31311 PAGE 1 OF 1 PROJECT: JOB NO: LOCATION: BY: LWW CLIENT: DATE: HYDROGRAPH RETENTION AREA TRACT 3131 -1 -.._ USE RCFCD HYDROLOGY MANUAL PLATE E -5.9 FOR RAINFALL PATTERN. USE 100- YEAR 6 -HOUR PRECIPITATION = 2.5" DEVELOPMENT = 60% IMP DRAINAGE AREA "133" SOIL TYPE A (PLATE D -5.1) TOTAL DRAINAGE AREA = 6.72 AC (1) (2) (3) INCL. NET PERIOD RAINFALL Q VOL. PREV. ST PERC. CUM. STOR. (HOUR) % INS. (PER HR) C C.F.S. (C.F.) (C.F.) (C.F.) (C.F.) 1 1.7 0.043 0.589 0.170 613 2 1.9 0.048 0.590 0.190 685 3 2.1 0.053- 0.591- 0.210- 758-- 4 2.2 0.055 0.591 0.218 786 5 2.4 0.060 0.592 0.239 859 . 6 2.4 0.060 0.592 0.239 859 7 2.4 0.060 0.592 0.239 859 8 2.5 0.063 0.592 0.251. 902 9 2.6 0.065 0.593 0.2% 932' 10 2.7 0.068 0.593 0.271 976 11 2.8 0.070 0.593 0.279: 1,004 12 3.0 0.075 0.594 0.300 1,078: 13 3.2 0.080 0.594 0.319, 1,150' 14 3.6 0.090 0.595 0.360, 1,295' 15 4.3 0.108 0.596• 0.433 1,557" 16 4.7 0.118 0.597 0.473 1,704'° 17 5.4 0.135 0.601. 0.545 1,963 18 6.2 0.155 0.602 0.627 2,257 19 6.9 0.173 0.603 0.701 2,524 20 7.5 0.183 0.604 0.743 2,674 21 10.6 0.269, 0.613 1.092 3,930 22 14.5 0.363 0.621 1.515 5,453 23 3.4 0.085 0.594 0.339 1,221 24 1.0 0.025 0.585 0.098 354 (1) RAINFALL = % OF TOTAL PERCIPITATION (2) Q= RAINFALL x C x A (INS, PER HOUR) (3) V = Q x 3600 = c.f. / HR A = _ 72 ACRE SOIL TYPE "A" C = COEFF. FOR 60% IMP (4) PERC RATE =.9" PER HOUR = .075' PER HOUR (FROM PLATE E-6.2) G: /Administration /COST ESTIMATES/HYDROGRAPH.wb3 6 HOUR G: /Administration/COST ESTIMATES /HYDROGRAPH.wb3 TOTAL VOL INCL. NET PERIOD REQ PREV. STOR. PERC. CUM. STOR. (A2, B1, 133) (C.F.) (C.F.) (C.F.) 1 2,082 2,082 177 1,905 2 2,328 4,233 177 4,056 3 2,576 6,632 353 6,279 4 2,671 8,950 353 8,597 5 2,918 311,515 353 11,162 6 2,918 14,080 353 13,727 7 2,918 16,645 353 16,292 8 3,068 19,360 423 18,937 9 3,169 22,106 423 21,683 10 3,316 24,999 423 24,576 11 3,411 27,987 423 27,564 12 3,663 31,227 497 30,730 13 3,909 -... 34,639. 497 34,142 -- 14 4,404 38,546 497 38,049 • 15 5,315 43,364 497 42,867 16 5,816 48,683 497 48,186: 17 6,695 54,881 568; 54,313 ": 18 7,700 62,013 568. 61,445 19 8,607 70,052: 568°. 69,4841- 20 9,119 78,603' 64& 77,955: 21 13,431: 93,386- 648:: 90,73& 22 18, 638: 109,376 737. 108,639i: 23 4,143 112, 782. 737" 112,045i 24- 1,201 113,246 737 112,509- G: /Administration/COST ESTIMATES /HYDROGRAPH.wb3 Earth Systems Ww" Southwest 79 -811B Country Club Drive Bermuda Dunes, CA 92203 (760) 345 -1588 (800) 924 -7015 FAX (760) 345 -7315 April 14, 2004 Santa Rosa Development, Inc. 46 -753 Adams Street La Quinta, California 92253 Attention: Mr. Joe DeCoster Project: Tentative Tracts 31310 and 31311 Northeast Corner of Adams Stripet and Avenue 48 La Quinta, California File No.: 09370 -01 .04 -04 -777 Subject: INFILTRATION TESTING FOR STORM WATER DISPOSAL Reference: Earth Systems Southwest, Geotechnical Engineering Report, Tentative Tract 31310 and 31311, NEC Adams Street and Avenue 48, La Quinta, California, File No.: 09370 -01, Report No.: 03 -10 -823, dated October 23, 2003. Dear Mr. DeCoster: This report presents the results of subsurface exploration and infiltration testing conducted at the subject site. The purpose of testing was to perform infiltration testing of the subsurface soils at' the site and to provide infiltration rates to be used in the design of open retention basins. Field Exploration Four exploratory borings were drilled to depths of approximately 15 to 20 feet below the existing: ground surface to observe the soil profile. These borings were located as close as practical to stakes placed by the client on the subject tracts. The borings were drilled on March 30, 2004> using 8 -inch outside diameter hollow -stem augers, powered by a CME 55 truck- mounted drilling rig. The borings served as logging holes as well as test holes. The testing was accomplished on April 1, 2004. The approximate boring locations are shown on Figure 1, attached to this report. Infiltration Testing Four infiltration tests were performed within the boreholes drilled in the approximate locations as shown on the attached Figure 1. The tests were conducted using 8 -inch diameter drilled boreholes made to depths of approximately 15 to 20 feet below existing ground surface. A 3`/4 -inch diameter perforated pipe was set in the borehole, encased with a filter fabric sock prior to insertion, and backfilled with native soil around the pipe. Water was injected at a relatively constant rate until a desired stabilized head of water was established. The level of the stabilized water was determined by the proposed bottom elevation of the retention basin. Based on US Bureau of Reclamation methodology for a pump -in test, the following hydraulic conductivity rates were obtained. April 14, 2004 -2- File No.: 09370 -01 04 -04 -777 Hydraulic Conductivity Bottom of Hole Water Head Flow Rate for Open Basins Borin feet feet (gpm) (in/hr) (gal /sf/day) P -1 15 9.7 1.4 0.7 11 P -2 18 9.9 1.9 0.9 14 P -3 15 9.0 2:0 1.1- 1.7- - P -4 16 9.7 4.0 2.0 30 As can be seen by the data, there is some variability in the infiltration rates at the subject site. The borings indicated some variability in the grain size and the proportions of silt in the sandy soils. The designer of the disposal system should decide on an appropriate factor of safety to apply to reported infiltration rates. Some of the factors that could affect the infiltration rates in basin areas are planting of ground cover vegetation., such as lawn; accumulated silts jand road oil from continued use; wind blown sand; and routine. maintenance. A silt and oil trap placed at influent points may be considered to reduce the potential for reduction in the infiltratio.rr-fate of soils. Limitations Our findings and recommendations in this report are based on selected points of field, exploration. Furthermore, our findings and recommendations are based on the assumption that: soil conditions do not vary significantly from those found at the specific exploratory location. Variations in soil or groundwater conditions could exist beyond the exploration points. The nature and extent of these variations may not become evident until construction. This report is issued with the understanding that the owner or the owner's representative has the responsibility to bring the information and recommendations contained herein to the attention of the engineers for the project so that they are incorporated into the plans and specifications for the. project. It is further understood that the owner or the owner's representative is responsible for submittal of this report to the appropriate governing agencies. As the Geotechnical Engineer of R6cord for this project, Earth Systems Southwest (ESSW) has striven to provide our services in accordance with generally accepted geotechnical engineering practices in this locality at this time. No warranty or guarantee is expressed or implied. This report was prepared for the exclusive use of the Client and the Client's authorized agents. Should you have any questions concerning our report, please give us a call and we will be pleased to assist you. Sincerely, EARTH SYSTEMS S AV Shelton L. Stringer GE 2266 Perc /sls /reh �266No. �} ` Exp.6 -30 -04 Distribution: 2 /Santa Rosa Development, Inc. 1 /RC File 2/BD File Attachment: Figure 1 — Site Exploration Plan EARTH SYSTEMS SOUTHWEST LEGEND O Approximate Percolation Location Not to Scale Figure 1 - Site Exploration Plan Tentative Tract 31310 & 31311 La Quinta, California Earth Systems 10 Southwest 04/23/04 . File No.: 09370 -01 HYDROLOGY HYDRAULIC CALCULATIONS r m v N R C F C a W C O HYDROLOGY . J\i]ANUAL RATIONAL METHOD CALCULATION FORM PROJECT TrGc 731-3 Id FREQUENCY o Sheet Na_ of ,Sheets Calculated by Che.tked by •'------- —�' D RAINAGE RIM,. REMARKS MRS gyp_ 5 LIMITATIONS: e Tc' L length =1000' 2. Maximum area = 10 Acres Q 100 1000 �. 90 900 0 80 C 800 -- 400 300 70- -- ` 700 200 c N 60 p = 100 c . ° - ° so s$ 600 a 50 CL. (1) 2 c 0 20 m m 10 m E 0 500 II U. U 0 �. 12 c 35 m w Ck 0 14 '~ N 400 c m. 30 m 350 JID 25 v � c o 300. � 18 c 19. - 20 20 v: :: 19: 0- 25.0 .: O; c . 15, t w C: c a 0-200 25 13 c 12 8 1 II 0 150 9 i 8' 7 100 5 LIMITATIONS: e I. Maximum. length =1000' 2. Maximum area = 10 Acres Q Q �. H 0 C c 400 300 c ` 200 c N 06 p = 100 o . ° - ° so s$ E o 30 CL. (1) 2 c c 20 m 10 10 K Undeveloped Good Cover Undeveloped Fair Cover Undeveloped Poor Cover ..Single Family (1/4 Acre) Commercial, (Pav 1-4 RCPC a. WIC D HYDROLOGY MANUAL m 2 w • c L m m c m w w W Tc 5 --i b e U Q 7 C m 8 c m 9-0 10 E II U. U m �. 12 c 0 14 '~ N 15 m. 16 r: 18 19. 20 v: :: O O; . w C: 25 c' KEY L-H -Tc -K -Tc w o 30 EXAMPLE: i= (I.) L =550'2 .H =5.0, K = Single Family(1 /4 Ac.) 35 Development , Tc =12.6 min. (2) L = 550';. H =5.0', K Commercial 40 Development , Tc = 9.7-min. Reference :.8ibfiography. item--Nix-;35.' PLATE D -3 iy a. ,I6 . -1 319 , 005- = 3; Z8 >=,�; _ 04 3, Z8 9,24 = 30, 31 d .P5 ' 2 571? rC7- = 51 U2 C frS w S 3-Z8 . - . ' VA = 3,33 -A 12,iZ _ 4- D, 3e IrS { �' 1 . r m D N O ft al r.. v o n `< .`'J' D n r f4 RAINFALL INTENSITY - INCHES PER HOUR CATHEDRAL CITY I CHERRY VALLEY I CORONA ( DESERT NOT SPRINGS I ELSINORE,- YILDONAR DURATION FREQUENCY MINUTES 10 100 YEAR YEAR 5 4.14 6.76 6 3.73. 6.08 7 3.41 S.S6 B 3.15 S.15 9 2.95 4:81 10 2.77 4.52 11 2.62 4.26 12 2.49 4.07 13 2.38 3.88 14 2.26 3.72 15 2.19 3.SB 16 2.11 3.44 17 2.04 3.32 18 1.97 3.22 19 1.91 3.12 20 1.B5 3.03 . 22 1.7S 2.86 24 1.67 .2.72- 26 1.S9 2.60 28 1.52 2.49 30 1.46 2.39 32 1.41 2.30 34 1.36 2.22 36 1.32 2.15 38 1;28 2.09 40 1.24 2.02 45 1.16 1.89 50 1.09 1.78 55 1.03 1.68 60 .98 1.60 65 .94 1.S3 70 .90 1.46 75 .86 1.41 80 .83 1.35 85 .80 1.31 SLOPE s .580 D O N RATION F FREQUENCY SLOPE _ .550 DURATION FREQUENCY MINUTES 10 100 YEAR YEAR 5 3.10 4.TO -6 2.84 4.38 7 2.64 4.07 e 2.47 3.81 9 2.34 3.60 10 2.22 3.43 11 2.12. 3:27 12 2.04 3.14 13 1.96 3.02 14 1.89 2.92 15 1.83 2.82 16 1.77 2.73 17 1.72 2.66 IB 1.68 2.SB 19 1.63 2.52 20 1.59 2.46 22 1.52 2.35 24 1.46 2.25 26 1.40 2.17 28 1.36- 2.09 30 1.31 2.02 32 1.27 1.96 34 1.23 1.90 36 1.20 1.85 38 1.17 1.81 40 1.14 1.76 45 1.08 1.66 50 1.03 1.58 55 .98 1.51 60 .94 1.45 65 .90 1.40 70 .87 1.35 75 .84 1.30 80 .82 1.26 85 .80 1.23 SLOPE .480 DURATION MINUTES 5 6 7 e 9 10 11 12 13 14 15 16 17 18 19 20 22 24 26 28 30 32 34 36 38 40 45 50 55 60 65 70 75 BO 85 FREQUENCY 10 100 YEAR YEAR 4.39 .6.76 3.95 6.08 3.62 5.56 3.35 5.15 3.13 4.81 2.94 4.52 2.78 4.28 2.6§ 4.07 2.53. 3.88 2.42 3.72 2.32 3.58 2.24 3.44 2.16 3.32 2.09 3.22 2.03 3.12 1.97 3.03 1.86 2.86 1.77 2.72 1.69 2.60 1.62. 2.49 1.55 2.39 1.50 2.30 1.45 2.22 1.40 2.15 1.36 2.09 1.32 2.02 1.23 1.89 1.16 1.78 1.09 . 1.68 1.04 1.60 .99 1.53 .95 1.46 .91 :1.41 .88 1.35 .85 1.31 SLOPE = .580 DURATION MINUTES 5 6 7 e 9 10 11 12 13 14 15 16 17 18 19 20 22 24 26 28 30 32 34 36 38 40 45 50 55 60 65 70 75 80 as FREQUENCY 10 100 YEAR YEAR 3.23 4.94 2.96 4.53 2.75 4.21 2.58 3.95 2.44 3.73 2.32 3.54 2.21 3.39 2.12 3.25 2.04 3.13 1.97 3.02 1.91 2.92 1.85 2.83 1.80 2.75 1.75 2.67 1,.70 2.60 1.66 2.54 1.59 2.43 1.52 2.33 1.46 2.24 1.41 2.16 1.37 2.09 1.33 2.03 1.29 1.97 1.25 1.92 1.22 1.87 1.19 1.82 1.13 1.72 1.07 1.64 1.02 1.56 .98 .1.50 .9♦ 1.44 .91 1.39 .88 1.35 .85 1.31 .83 1.27. SLOPE _ .480 SLOPE .480 DURATION MINUTES 5 6 7 e 9 10 11 12 13 14 15 16 17 18 19 20 22 24 26 28 30 32 34 36 38 40 45 50 55 60 65 70 75 BO 85 FREQUENCY 10 100 YEAR YEAR 4.39 .6.76 3.95 6.08 3.62 5.56 3.35 5.15 3.13 4.81 2.94 4.52 2.78 4.28 2.6§ 4.07 2.53. 3.88 2.42 3.72 2.32 3.58 2.24 3.44 2.16 3.32 2.09 3.22 2.03 3.12 1.97 3.03 1.86 2.86 1.77 2.72 1.69 2.60 1.62. 2.49 1.55 2.39 1.50 2.30 1.45 2.22 1.40 2.15 1.36 2.09 1.32 2.02 1.23 1.89 1.16 1.78 1.09 . 1.68 1.04 1.60 .99 1.53 .95 1.46 .91 :1.41 .88 1.35 .85 1.31 SLOPE = .580 DURATION MINUTES 5 6 7 e 9 10 11 12 13 14 15 16 17 18 19 20 22 24 26 28 30 32 34 36 38 40 45 50 55 60 65 70 75 80 as FREQUENCY 10 100 YEAR YEAR 3.23 4.94 2.96 4.53 2.75 4.21 2.58 3.95 2.44 3.73 2.32 3.54 2.21 3.39 2.12 3.25 2.04 3.13 1.97 3.02 1.91 2.92 1.85 2.83 1.80 2.75 1.75 2.67 1,.70 2.60 1.66 2.54 1.59 2.43 1.52 2.33 1.46 2.24 1.41 2.16 1.37 2.09 1.33 2.03 1.29 1.97 1.25 1.92 1.22 1.87 1.19 1.82 1.13 1.72 1.07 1.64 1.02 1.56 .98 .1.50 .9♦ 1.44 .91 1.39 .88 1.35 .85 1.31 .83 1.27. SLOPE _ .480 CATCH BASIN'CALCULATIONS CATCH BASIN CAPACITIES H=.83' h =.74' H/h= 1.12 From BRP Chart 1073.03, Capacity= 2.3 CFS/Ft. CATCH BASIN #1 Qi00=1,85 CFS CATCH BASIN # 2 Qi00=16.49 CFS 16.49/2.3 = 7.17' CATCH BASIN # 3 Q100= 4.49 CFS 4.49/2.3 = 1.95' CATCH BASIN # 4 Q1oo= 5.92 CFS 5.92/2.3 = 2.57' Use 6.0' C.B. Use 8.0' C.B. Use Min. 4.0' C.B. Use Min. 4.0' C.B. /1 7. 0= Nth ' —z ; = S.�z ;,X. H J - Q = C AH to /O /0 6 2, 6.5 S 6 -� o f.o •6 .6 !r .R ,..� ti v moo►. .2 .S . lop .C' .� Qop v C ..Z .03 ..02 .2. ` /-J- /2 Loco/ Dep�FSS�bn lv1 O./ Label: DW Rim: 50.00 Sump: 47.( 0+00 0+20 Profile Scenario: Base Cr>9 t , E)w 4 k Label: CB #1 Rim"..-54.3.2 ft 56.00 Sum6l 50.82 ft Label: J71. Rim: 551,77--ft Sump: 47.55 ft 019aboon+A4 0 ------ 55.00 ............. 54.00 1 53.00 ... . . ....... 52.00 51.00 50.00 49.00 48.00 47.00 1+00 Label: Al -A Label:'LINE Al . -A , Up. Invert: 47.55 IL Up. Invert: 50.82 ft Dn. Invert: 47.05 ft Dn. Invert: 47.55 ft L: 38.83 ft L: 54.14 ft Size: 18 inch Size: 18 inch S: 0.0 12877 ft/ft S: 0.060399 ft/ft Bevati on (ft) Project Engineer. WD c: \haestad\academic\stmc \a1 -a.stm Academic Edition Storm CAD v4.1.1 [4.2014a] 02/16/05 09:07:14 AM Ha estad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 USA +1-203-755-1666 Page 1 of 1 Scenario: Base »» Info: Subsurface Analysis iterations: 1 »» Info: Convergence was achieved. Gravity subnetwork discharging at: DW 1 -------------------------------------------------=--------------- >>>> Info:- Loading and hydraulic computations completed successfully. »» Warning: CB #1 Flooding is occurring. Calculations continue with hydraulic grade reset. CALCULATION SUMMARY FOR SURFACE NETWORKS I Label I Inlet I Inlet I Total I Total I Capture I Gutter I Gutter I I I Type I I Intercepted I Bypassed I Efficiency I Spread I Depth I I I I I Flow I Flow I ( %) I (ft) I (ft) I I I I I (cfs) I (cfs) I I I I I--=---- I--------------- I---------------------- I------------- I CB #1 I Generic Inlet I Generic Default 100% I 0.00 -------------------------------------------------------------------------------------------------- I---------- I 0.00 I------------ I 100.0 1-------- I--- 1 0.00 1 - - - - -I 0.00 1 - - - - -- CALCULATION SUMMARY FOR SUBSURFACE NETWORK WITH ROOT: DW 1 I Label I Number I Section I Section I Length I Total I Average I Hydraulic I Hydraulic I I I of I Size I Shape I (ft) I System I Velocity I Grade I Grade I I I Sections I I I I Flow I (ft /s) I Upstream I Downstream I I I I I----------- I---------- I--------- I I I (cfs) -------- I ---------- I (ft) I (ft) I ------- - - - - - I Al -A I 1 1 18 inch I---------- I Circular I-------- I I 38.83 1 1.85 I 1 1.05 I----------- I 1 54.52 1 I 54.51 1 I LINE Al -A 1 1 1 18 inch --------------------------------------------------------------------------------------------- I Circular 1 54.14 1 1.85 1 1.05 1 54.53 1 54.52 1 - - - - -- I Label I Total I Ground I Hydraulic I Hydraulic I I I System I Elevation I Grade I Grade I I I Flow I (ft) I Line In I Line Out I I ------ I (cfs) I ----------- I (ft) I (ft) I I- I DW 1 I-------- 1 1.85 I 1 50.00 I ----------- 1 54.51 I------ - - - - - I 1 54.51 1 I J -1 1 1.85 1 55.77 1 54.52 1 54.52 1 I CB #1 ------------------------------------------------ 1 1.85 1 54.32 1 54.32 1 54.32 1 - - - - -- Completed: 02/16/2005 02:14:52 PM Project Engineer. WD c: \haestad\academic \stmc \a1 -a.stm Academic Edition StormCAD v4.1.1 (4.2014a] 02/16/05 02:14:57 PM Ha estad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 USA +1- 203 - 755 -1666 Page 1 of 1 Q1 .0.00 ft 47.05 0 +00 0 +20 Profile Scenario: Base C &O2 - 041 Label: CB #2 Rim: 55.77 ft 11t i Sumn- 52.27 ft Label: Al -13 """-%' Up. Invert: 47.50 ft Up. Invert: 52.27 ft Dn. Invert: 47.05 ft Dn. Invert: 47.50 ft L: 44.18 ft L: 64.20 ft Size: 21 inch Size: 21 inch S: 0.0 10 186 ft/ft S: 0.074299 ft/ft Elevation (ft) Project Engineer. WD c: \haestad\academic\stmc \a1 -b.stm Academic Edition StorrnCAD v4.1.1 [4.2014a] 02/16/05 10:46:41 AM Ha estad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 USA +1- 203 - 755 -1666 Page 1 of 1 Scenario: Base »» Info: Subsurface Analysis iterations: 1 »» Info: Convergence was achieved. Gravity subnetwork discharging at: 0 -1 ----------------------------------------------------------- »» Info: Loading and hydraulic computations completed successfully. CALCULATION SUMMARY FOR SURFACE NETWORKS I Label I Inlet I Inlet I Total I Total I Capture I Gutter I Gutter 1 I I Type I I.Intercepted I Bypassed I Efficiency I Spread I Depth 1 I I I I Flow I Flow I M I (ft) I (ft) I I I I------- I--------------- I I (cfs) I (cfs) I I I I I CB #2 I Generic Inlet -------------------------------------------------------------------------------------------------------- I---------------------- I------------- I---------- I Generic Default 100% I 0.00 I 0.00 I------------ I 100.0 I-------- I 0.00 I--- - - - - -1 I 0.00 1 CALCULATION SUMMARY FOR SUBSURFACE NETWORK WITH ROOT: 0 -1 I---------- I----------- 1 6.86 1 I------- 54.92 1 - - - - - I 54.51 1 I LINE Al -B I 1 1 21 inch I --------------------------------------------------------------------------------------------- I Label I Number I Section i Section I Length I Total I Average I Hydraulic I Hydraulic I I I of I Size I Shape I (ft) I System I Velocity I Grade I Grade I I I Sections I I I ------ I I Flow I (ft /s) I Upstream I Downstream I I I I I I----------- I---------- 50.00 I I (cfs) I I (ft) I (ft) I I--------- I---------- I Al -B I 1 1 21 inch I Circular I-------- I 44.18 I-------- 1 16.49 I---------- I----------- 1 6.86 1 I------- 54.92 1 - - - - - I 54.51 1 I LINE Al -B I 1 1 21 inch I --------------------------------------------------------------------------------------------- Circular I 64.20 1 16.49 1 6.86 1 55.51 1 54.92 1 - - - - -- I Label I Total I Ground I Hydraulic I Hydraulic I I I System I Elevation I Grade I Grade I I I Flow I (ft) I Line In I Line Out I I ------ I (cfs) I ----------- I (ft) I (ft) I I- l 0 -1 I-------- I I 16.49 1 50.00 I----------- 1 54.51 I------ - - - - - I 1 54.51 1 I J -1 I 16.49 1 55.77 I 54.92 I 54.92 1 1 CB #2 ------------------------------------------------ 1 16.49 1 55.77 I 55.51 I 55.51 1 - - - - -- Completed: 02/16/2005 02:11:33 PM Project Engineer. WD c:\haestad \academic \stmc \a1 -b.stm Academic Edition StormCAD v4.1.1 (4.2014a] 02/16/05 02:11:39 PM Ha estad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 USA +1- 203 - 755 -1666 Page 1 of 1 I . Profile Scenario:Base 60.00 Label: CB 3 ft Label: CB 4 SIM 2. 52 86 52.86 ft Rim: 5621 ft I 91 rnp: 53.21 ft 55.00 _1 50.00 'Label:: LINE A2-A ;Up. Invert 53.21 ft Dn. 3In.7v4ertft 5 2.97 ft Bevation (ft) Label: LINE A2-B U P Invert 52.86 ft :Sze, 18 inch CI 11- Invert 52.04 ft' I is: L:81.93ft 0.010110 ftlit Label: A2-8(3) Sze: 18 inch Llpii Invert 50.61 ft Label: -B 01010009 fV11 45.00 Label: DW 2 L: 54.96 ft Dn. Invert 50.61 ft Rim: 43.00 ft Sze: 18 in di L: 143.16 ft 50.189047 Mt Sze: 18 inch Sump: M04 It S 0.00 9989 ft4t Label: GRADE BREAK (1) —Rirn43-.00-ft--- 40.00 Sump: 4022 ft Label: A2-B(4) U . Invert4022ft DnInvert 39.04 ft L: 14.00 ft Sze: 18 inch S 0.08 4286 ftfft I — — - — - — — — ------ 35.00 0+00 0+50 1+00 1+50 Station (ft) 2+00 2+50 3+00 3+50 Title: STORM Project Engineer. WatsonWWzon c:\haestad\academic\stMC\31311 2.11.05.Stm Academic Edition StormCAD v4.1.1 [4,2014a) 02/15/05 09:36:50 AM Ha estad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 USA +1-203-755-1666 Page 1 of I Scenario: Base »» Info: Subsurface Analysis iterations: 1 »» Info: Convergence was achieved. Gravity subnetwork discharging at: DW 1 »» Info: Loading and hydraulic computations completed successfully. »» Warning: GRADE BREAK (2) Flooding is occurring. Calculations continue with hydraulic grade reset. »» Info: LINE B3 -B Hydraulic jump formed. »» Info: LINE B3 -B Critical depth assumed upstream. »» Info: LINE B3 -A Hydraulic jump formed. »» Info: LINE B3 -A Critical depth assumed upstream. »» Warning: B3 -A Pipe discharge-is above full flow capacity. »» Info: Subsurface Analysis iterations:. 1 »» Info: Convergence was achieved. Gravity subnetwork discharging at: DW 2 »» Info: Loading and hydraulic computations completed successfully. »» Warning: GRADE BREAK Flooding is occurring. Calculations continue with hydraulic grade reset. »» Warning: GRADE BREAK (1) Flooding is occurring. Calculations continue with hydraulic grade reset. »» Info: LINE B1 -A Hydraulic jump formed. »» Info: LINE B1 -A Critical depth assumed upstream. »» Warning: LINE B1 -A(2) Pipe discharge.is above full flow capacity. »» Info: LINE A2 -A Hydraulic jump formed. »» Info: LINE A2 -A Critical depth assumed upstream. »» Info: A2 -B(3) Hydraulic jump formed. »» Info: A2 -B(3) Critical depth assumed upstream. »» Info: Subsurface Analysis iterations: 1 »» Info: Convergence was achieved. Gravity subnetwork discharging at: DW 3 »» Info: Loading and hydraulic computations completed successfully. »» Warning: TIE IN Flooding is occurring. Calculations continue with hydraulic grade reset. »» Warning: LINE B2 -C Pipe fails minimum cover constraint. »» Warning: LINE B2 -C Pipe discharge is above full flow capacity. »» Info: B2 -A Hydraulic jump formed. »» Info: B2 -A Critical depth assumed upstream. CALCULATION SUMMARY FOR SURFACE NETWORKS I Label I Inlet I Inlet I Total I Total I Capture I Gutter I Gutter I I I Type" I I Intercepted I Bypassed I Efficiency I Spread 1 Depth I I I I I Flow I Flow I M i (ft) I (ft) I I I I I (cfs) I (cfs) I - -- I— - i- - - - - -- I----- - - - - -- i----------- - - - - -- I----- - - - - -- I CB 6 1 Generic Inlet I Generic Default 100°% 1 0.00 I- - - - - -- I 0.00 I- - - - - -- I 100.0 1 0.00 1 0:00 I. Title: STORM Project Engineer. Watson Watson c:lhaestadlacademiclstmc131311 2.11.05.stm Academic Edition StormCAD. v461.1'(42014aj tl 02/15/05 03:41:20 PM He estad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 USA +1- 203 -755 -1666 , Pagerl:of3 CB 5 1 Generic Inlet I Generic Default 100% I 0.00 1 0.00 I 100.0 1 0.00 I 0`: ao 1•" CB 3 1 Generic Inlet I Generic Default 100% I 0.00 1 0.00 I 100.0 I 0.00 I 0.00:1 CB 4 1 Generic Inlet I Generic Default 100% I 0.00 I 0.00 I 100.0 I 0.00 1 0 :00,1' CB 8 1 Generic Inlet I Generic Default 100% I 0.00 I 0.00 1 100.0 1 0.00 I 0.00 I CB 7 1 Generic Inlet I Generic Default 100% I 0.00 .1 0.00 1 100.0 1 0.00 1 0.00 I CB 9 1 Generic Inlet I Generic Default 100% I 0.00 I 0.00 1 100.0 1 0.00 1 0.00 I CB 11 1 Generic Inlet i Generic Default 100% I 0.00 1 0.00 I 100.0 1 0.00 I 0.00 1 CB 10 1 Generic Inlet I Generic Default 100% I 0.00 1 0.00 I 100.0 1 0.00 I 0.00 1 CALCULATION SUMMARY FOR SUBSURFACE NETWORK WITH ROOT: DW 2 I Label I Number I Section I Section I Length I Total I Average I Hydraulic I Hydraulic I I I of I Size I Shape I (ft) I System I Velocity I Grade I Grade I I I Sections I I 43.aO I I Flow I (ft /s) I Upstream I Downstream I I I-------------- I I---------- I I--------- I I---------- .43.00 I. I I-------- I (cfs) I CB 6 I (ft) I - (ft) I I LINE B1 -A(2) 1 1 1 18 inch I Circular 1 14.00 I-------- I---------- 1 20.60 1 11.66 I--------- I------- 1 50.04 1. - - - - - I 49.58 1 . I A2 -B(4) I 1 1 18 inch I Circular 1 14.00 1 10.41 1 5.89 1 49.70' 1 49.58 1. I LINE B1 -A 1 1 1 18 inch I Circular 1 104.08 1 20.60 1 11.68 1 53.72 1 43.00 1 I A2 -B(3) 1 1 1 18 inch I Circular 1 54.96 1 10.41 1 6.27 1 51'.85 1 43.00 I I LINE B1 -B 1 1 1 18 inch.1 Circular 1 23.74 1 10.30 1 6.90 1 54.74 1 54.39. 1: I A2-B- I 1 1 18 inch I Circular 1 143.16 1 10.41 1 6.98 1 53.28 1 51.74 1 I LINE A2 -B 1 1 1 18 inch I Circular 1 81.93 1 10.41 1 6.98 1 54.10 1 53.17 1 1 LINE A2 -A 1 1 1 18 inch 1 Circular 1 23.74 1 5.92 1 4.61 1 54.15 1 54.10 1 Label I Total I Ground I Hydraulic I Hydraulic I (ft) I System I Elevation I. Grade I Grade 1 GRADE BREAK (2) I 15.74 1 I Flow I (ft) I *Line In I Line Out I ----------------- I (cfs) I 1--------- I---------- 1 18.inch 1 I (ft) I (ft) I DW 2 I-------- I---------- 1 31.01 I 43.aO I----------- I----------- I 49.58 I 1. 49.59 1 GRADE BREAK 1 20.60 1 43.00 1 43.00 1 43:00 1 GRADE.BREAK (1) 1 10.41 1 .43.00 I. 43.00 I 43.00 I CB 6 1 20.60 1 57.59 1 53.72'1 53.7.2 I MH 2 1 10.41 1 58.70-1 51.85 1 51.85 1 CB 5 1 10.30 1 57.59 1 54.74 1 54.74 1 MH 1 1 10.41 1 59.06 I 53.28 I 53.28 1 CB 3 1 10.41 1• 56.21 1 54.10 1 54.10 1 CB 4 1 5.92 1 56.21 1 54.15 1 54.15 .1 CALCULATION SUMMARY FOR SUBSURFACE NETWORK WITH ROOT: DW 1 Label I Number I Section I Section I Length (ft) I of I Size I Shape I (ft) GRADE BREAK (2) I 15.74 1 I Sections I I I I I 54.49 I I --- - - - - -- I---------- B3-A 1 1 1--------- I---------- 1 18.inch 1 Circular I-------- 1 5.00 LINE B3 -A I 1 1 18 inch I Circular 1 83.36 LINE B3 -a 1 1 118 inch I Circular 1 23.74 Label I Total I Ground I System I Elevation I Flow I (ft) j.'..(cfs) I Grade I DW 1 I 15.74 1 43.00 GRADE BREAK (2) I 15.74 1 43.00 CB 8 I 15.74 1 54.49 Total I Average .1 Hydraulic I Hydraulic I System I Velocity I Grade I Grade I Flow I (ft /s) I Upstream 1 Downstream I (cfs) - ------- I 1 (ft) . 1 (ft) I - - - - - 15.74 I-------=-- I---------- 1 8.91 1 I------- 49.68 I I 49.58 1 15.74 I 9.00 1 52.08 I 43.00 1 7.87 1 5.27 1 52.09 1 52.08 1 Hydraulic I Hydraulic I Grade I Grade I Line In I Line Out I (ft) - - - - -- I (ft) I -- - - - - -- ----- 49.58 I I 1 49.58 I 43.00 I 43.00 1 52.08 I 52.08.1 Title: STORM Pmject Enginf er- Watson Watson c:lhaestadlacademiclstmc131311 2.11.05.stm Academic Edition StormCAD v4.1.1 [42014a]; 02/15/05 03:41 :20 PM Ha estad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 USA +1 -203- 755 -1666 Page•2 of 3 CB 7 1 7.87 I 54.49-1 52.09 1 52.09 1 -------------------------------------------------------------- CALCULATION SUMMARY FOR SUBSURFACE NETWORK WITH ROOT: DW 3 Label I Number I Section I Section 1 Length I of I Size I Shape 1 (ft) I I Sections I I I I I I (ft) - - -----------I----------I---------I---------I-------- LINE B2 -C 1 1 1 18 inch I Circular 1 5.00 B2 -C 1 1 1 18 inch 1 Circular I 27.69 LINE B2 -B I 1 1 18 inch I Circular I 47.37 LINE B2 -A 1 1 1 18 inch I Circular 1 45.92 B2 -B 1 1 118 inch I Circular I 27.30 B2 -A 1 1 1 18 inch I Circular 1 22.82 Total I Average I Hydraulic I Hydraulic I System I Velocity 1 Grade I Grade 1 Flow 1 (ft /s) I Upstream I Downstream I (cfs) ------- I' I (ft) I (ft) - - 10.59 I---------- 1 5.99 I---------- I'------ I 57.82 1 - - -I 57.70 1 6.93 1 4.02 I 56.08 1. 56.00 1 1.83 I 1.31 1 55.99 1 56.00 1 1.83 1 1.74 1 55.94 1 56.00 I 1.83 I 2.13 1 55.95 1 55.99 1 1.83 1. 2.95 I 56.02 1 55.94 1 I Label I Total I Ground I Hydraulic I Hydraulic 1 I I System I Elevation I Grade I Grade 1 I I Flow I (ft) . I Line In I Line Out 1 I I I- ------ (cfs) I I (ft) I (ft) I - - - - - I-------- I DW 3 1 10.59 I----------- I--------- 1 56.00 1 57.70 I------ I 1 57.70 1 I TIE IN 1 10.59 1. 56.00 1' 56.00 1 56.00 I I CB 9 1 6.93.1 61.03 1 56.08 1 56.08 1 I J -5 1 1.83 1 61.30 I 55:99 1 55.99 1 I GB 1 1.83 I 61.20 I 55.94 1. 55.94 1. I CB 11 1 1.83 I 61.20 I 55.95 1 55.95 1. I CB 10 .I .1:83 I. 61.57 1 56.02 1 56.02 1 Completed: 02/15/2005 03:40:00 PM Title: STORM Project Engineer: Watson Watson cAhaestaMacademiclstm631311 2.11.05.stm Academic Edition StorMCAD v4: 1.1,[412014a] 02/15/05 03:41:20 PM Ha estad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 USA +1- 203 -755 -1666 Page 3 of 3 SAND FILTER STANDARDS AND CALCULATIONS 36" CLEAR SPACE 64 NUISANCE WATER INLET C FINE SAND, 33" DEEP — FILTER FABRIC COURSE ROCK FOOTING — STEEL GRATE, THREE (3) SECTIONS W4x13 SUPPORT BEAU GROUND fa VINT Assmy MODIFIED PRECAST UTILITY VAULT (TVO PIECES) ELEVATION VIEW DRAIN LINE . ,,— ARCH -TYPE LEACH LINE COURSE ROCK LENGTH AS SPECIFIED ON PROJECT PLANS PLAN VIEV REVISIONS: APPROVED 08/21/01 STANDARD CHRIS A. VOGT CITY ENGINEER 3 70 RCE 44250 SAND FILTER SHEET 1 OF 7 BI � B2 QR A L— BI B2 7TI ON A-A PLAN VIEV DETAIL 1, PAGE 3 OF la Li Li DETAIL 2, PAGE 3 OF 6 ib DETAIL 3, PAGE 3 OF 6 SECTION BI -BI SECTION B2 -B2 I a PRECAST UPPER VAULT SECTION - 8' -0" x 6' -0" x 4'-0" I.D. I b PRECAST LOVER VAULT SECTION - 8' -0" x 6' -0" x 3' -0" I.D O2 CAST-IN-PLACE CONCRETE FLOOR O3 CAST-IN-PLACE CONCRETE FOOTING REVISIONS: APPROVED STANDARD 08/21/01 �W CHRIS A. VOGT 3 70 CITY ENGINEER RCE 44250 SAND FILTER SHEET 2 OF 7 2' 4' 32' DETAIL 2 DETAI! 1 4 2° 1 S. t' DETAIL 4 4" 32' DETAIL 3 16" 4" 4° Ib PRECAST LOVER HALL F1ECE CAST-IN -PLACE CONCRETE FLOOR 1520- C-2500 CAST -IN -PLACE CONCRETE FOOTING 1520 -C -2560 REVISIONS: APPROVED 08/21101 o Q �/ STANDARD s O D CHRIS A. VOGT " °� 370 CITY ENGINEER SAND FILTER (floor & footing RCE 44250 details SHEET 3 OF 7 96' 4' Nk 88. 4" 4' 32' DETAIL 2 DETAI! 1 4 2° 1 S. t' DETAIL 4 4" 32' DETAIL 3 16" 4" 4° Ib PRECAST LOVER HALL F1ECE CAST-IN -PLACE CONCRETE FLOOR 1520- C-2500 CAST -IN -PLACE CONCRETE FOOTING 1520 -C -2560 REVISIONS: APPROVED 08/21101 o Q �/ STANDARD s O D CHRIS A. VOGT " °� 370 CITY ENGINEER SAND FILTER (floor & footing RCE 44250 details SHEET 3 OF 7 DETAIL C O 1' -2' OPEN GRADED GRAVEL SO 34' WIDE x 15' HIGH ARCH-TYPE CHAMBER O NON -WOVEN GEDTEXTILE ENGINEERING FABRIC 7O 10' DIR. IRRIGATION VALVE BOX BO 1'x15Q' SCHEDULE 40 PVC TEE 9O SAND REVISIONS: APPROVED 08/21/01 CHRIS A. VOGT CITY ENGINEER RCE 44250 DETAIL E G li I� FLOW TO LEALD FIELD ji DETAIL D 10 2'O.D. SCHEDULE 40 PVC PIPE II 4'O.D. PERFORATED SCHEDULE 40 PVC PIPE 12 4'O.D. SCHEDULE 40 PVC COUPLING 13 4' O.D. SCHEDULE 40 PVC PIPE 14 4'x45Q' SCHEDULE 40 PVC TEE IS 4' SCHEDULE 40 PVC PIPE CAP T4'1�v 4 XPQg&m SAND FILTER I, II lk0 000 DETAIL F STANDARD 370 SHEET 4 OF 7 NATIVE GROIN I. :.j.Y:�,2 �� , . � SOIL _ t• 2'uiv..... '..... /irk o r: o - lk 3B' SECTION .. DETAIL C O 1' -2' OPEN GRADED GRAVEL SO 34' WIDE x 15' HIGH ARCH-TYPE CHAMBER O NON -WOVEN GEDTEXTILE ENGINEERING FABRIC 7O 10' DIR. IRRIGATION VALVE BOX BO 1'x15Q' SCHEDULE 40 PVC TEE 9O SAND REVISIONS: APPROVED 08/21/01 CHRIS A. VOGT CITY ENGINEER RCE 44250 DETAIL E G li I� FLOW TO LEALD FIELD ji DETAIL D 10 2'O.D. SCHEDULE 40 PVC PIPE II 4'O.D. PERFORATED SCHEDULE 40 PVC PIPE 12 4'O.D. SCHEDULE 40 PVC COUPLING 13 4' O.D. SCHEDULE 40 PVC PIPE 14 4'x45Q' SCHEDULE 40 PVC TEE IS 4' SCHEDULE 40 PVC PIPE CAP T4'1�v 4 XPQg&m SAND FILTER I, II lk0 000 DETAIL F STANDARD 370 SHEET 4 OF 7 PLAN VIEW OF GRATE VANDAL -PROOF BOLT GRATE FASTENER BEARING BARS (TYPICAL) r -BEAN FLANGE \ TACK WELD NUT TO FLANGE UNDERSIDE C- C A 0 TYPICAL LOCATION FOR GRATE FASTENER B- B REVISIONS: APPROVED 08/21/01 �IGNNW STANDARD CHRIS A. VOGT ^```'TM ±` 37'0 CITY ENGINEER / RCE 44250 GRATE FRAMING. DETAILS FSHEET 5 OF 7 SANDFILTER SIZING CALCULATIONS Calculation #1 Determines how many standard size sandfilters are needed. No.* of Sandfilters = ZZ homes - 40 homes /sandfilter * Round all fractions up to the nearest whole number Each sandfilter has 48 sf of filter surface (ie 6' x 8'); assume the incoming nuisance water will percolate through the sand at the rate of 4.6 inches per hour. The sandfilter must be sized to handle the "surge inflow rate" of 0.458 cf /house /hour, which is based on the assumption that, on average, each house releases 12 gallons in a 3.5 hour "surge" period. Therefore, each sandfilter is capable of handling 18.4 cf /hour. As a result, each,sandfilter can handle the nuisance water released by 40 homes (18.4/0.458 =40). Calculation #2 - Determines how long the leach line must be. Leach Line Length* homes x 1.9 Whome (sandy soil) 4Z LF, " In feet to be divided evenly between the number of sandfilters Leach Line Length* = homes x 3.8 If /home (silty soil) * In feet to be divided evenly between the number of sandfilters The critical aspect in sizing the leach line length is related to its ability to maintain a sustained percolation rate (ie 24 -7 -365) in saturated soil, therefore, for the purposes of this calculation, it is assumed that the sustained percolation rate in saturated soil is 0.25 in /hr.(Note: if the soil is silty, more than 5% by weight passing the 200 sieve, the percolation rate shall be reduced to 0.125 in /hr). The leach line arch provides 2.8 sf of'percolation surface per lineal foot of leach line length. If the average nuisance water discharge per house in the neighborhood is 20 gallons per day that means each house must have 5.35 sf of percolation area in the leach field to percolate its 24-hr nuisance water discharge. Therefore, the leach line length must be 1.9 If /home. REVISIONS: APPROVED dw , 08/21/01. STANDARD CHRIS A. VOGT �� CITY ENGINEER RCE. 44250 SAND FIL TER SHEET 6 OF 7 SANDFILTER Materials Specifications • Precast Vnidt Structure - The vault structure shall be a precast utility vault manufactured in two sections: 1 -36" section, and 1 -48" section, similar to Part No. 6080W7- QTA370 as manufactured by J&R Concrete Products, Inc., of Perris, CA (1- 909 - 943 - 5855), or approved equal. A galvanized steel frame to accommodate the grate shall be fitted per Sheet 5 of 7 prior to casting the top section. • SandfiitPr C;rntp - The sandfilter grate shall be galvanized welded steel bar, Model GW -100 with (1 x 3/16" bars) and banded ends, as manufactured by the .McNichols Co. (1- 800 - 237 - 3820), or approved equal. Four (4) grate panels measuring 37" x 49" shall be provided, (Note: Gross opening size is 8' -3" x 6'- 3"). Use CB saddle type retainer clips as manufactured by McNichols, or an approved alternate method to secure the grates. • Si,nnnrt Ream - The grate support beam shall be W4x13, 8' -2" long, Fy =36 ksi steel. • i Pnch I inP - The leach line shall be constructed of arch -type chamber sections, High Capacity Infiltrator- model, as distributed by Boyd Tanks Co. (1- 909 -657- 6966), or approved equal. • FnginPPring Fahrir. -'The engineering fabric shall be fine spun non - woven, Dupont's Typar Style 3601, as distributed by Aldrich Supply Co (1- 909 -371- 3018), or approved equal. • Fiiter Sand - The fine filter sand shall be, 100% passing a.No. 45 sieve (.35mm) with a uniformity coefficient between 2 and 3. REVISIONS: APPROVED STANDARD ooioo/oa �iG�i(/ CHRIS A. VOGT " °`4.4 370 CITY ENGINEER . RCE 44250 SAND FI L TER SHEET 7 OF 7 Til4t 4 lwQu;xrw MEMORANDUM TO: All Interest Persons FROM: Steve Speer, Senior Engin DATE: October 12, 1998 RE: Nuisance Water Sandfilter The La Quinta Nuisance Water Sandfilter is designed to clarify nuisance water before passing the water into a leach line or leach field. Past experience has demonstrated that nuisance water handling systems, such as "drywells" or "french drains" which typically percolate unfiltered water eventually fail to percolate the water because pores in the soil surrounding the leach line or percolation chamber become.clogged with mud, silt, cement, and other fine material that falls in the street and is washed into the storm drain system. When this occurs, the useful life of the drywell or french drain has ended and must be replaced if percolation is intended. The La Quinta Nuisance Water Sandfilter utilizes gravity sandfilter technology that was widely used in 191', and early 20'", century municipal water systems. In those simple water treatment systems, the raw water was passed through a 3 to 4 feet thick sandfilter, chlorinated, and introduced to the potable water system. The sand in the sandfilter is very effective in clearing fine material from the water. As a result, only filtered water reaches the leach field, thus keeping the leach field and pores in the soil from becoming clogged. The sandfilter is easy to maintain. Simply remove the grates from the top of the sandfilter, and remove the upper 6 inches of sand without replacement. This can be repeated a second time without replacing the sand. The third time 6 inches of sand is removed, 18 inches of clean sand should be added to the sandfilter. The 6 -inch sand removal effort should occur whenever the sandfilter is functioning too slow to handle the incoming nuisance water. Note, there should always be at least 21 inches of filtering sand in the sandfilter when it is in operation, otherwise the sand filter bedding is too thin and may allow fines to reach the filter fabric laying on top of the course rock at the bottom of the vault If the filter fabric is plugged with fines, it too must be replaced. Never operate the filter without the filter fabric separating the sand from the course rock. Doing so allows the sand and other fine material in the nuisance water to be carried into the course rock and eventually into the leach field. . If you have questions regarding the sandfilter, or its operation, please call me at (760) 777- 7043. REVISIONS: APPROVED 08/21/01 STANDARD CHRIS A. VOGT !c`" 370 CITY ENGINEER RCE 44250 SAND FILTER SHEET 7A OF 7 INDICATES RETENTION BASIN DRAINAGE AREA INDICATES Q10 AND QIOO SUB-AREAS a V RETENTION BASIN DRAINAGE PLAN TRACT 31310/31311 OCTOBER 12, 2004 w I LL SITE it.j. 46RCI NO. 30420 C> tea► ►� \��:.. .,..�� I 11(fil B3-2 1 t % WWWA I I W iJ EXISTING DRAINAGE PATTERN TRACT 31310/31311 SEPTEMBER 17, 2004 ,ZT at rZ `j � • W � O • � CZ O ssa „ xs � two a � o Gi Qa x, d 077711 _ T.- 1" =140' f I - t % WWWA I I W iJ EXISTING DRAINAGE PATTERN TRACT 31310/31311 SEPTEMBER 17, 2004 ,ZT at rZ `j � • W � O • � CZ O ssa „ xs � two a � o Gi Qa x, d 077711 _ T.- 1" =140' APR