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HomeMy WebLinkAboutHolland DevelopmentRough Grading Hydrology Study for Holland Development Lytle Creek Fontana, California January 3, 2008 Prepared for IHOLLAND PARTNERS Prepared • KHR ASSO IATES CONSULTING ENGINEERS/SURVEYORS/PLANNERS 4100 Newport Place Drive - Suite 200 Tel (949) 756-6440 Newport Beach, California 92660 Fax (949) 756-6444 M- , ATTESTATION This report has been prepared by, and under the direction of, the undersigned, a duly Registered Civil Engineer in the State of California. Except as noted, the undersigned attests to the technical information contained herein, and has judged to be acceptable the qualifications of any technical specialists providing engineering data for this report, upon which findings, conclusions, and recommendations are based. // tames"awamiurV,P.E. Registered Civil Engineer No. C30560 Date: January 3, 2008 Qo TABLE OF CONTENTS Introduction.................................................................................................................... 1 ExistingConditions....................................................................................................... 1 ProposedProject........................................................................................................... 2 HydrologyStudy Guidelines......................................................................................... 3 Infiltration Rate vs. SCS Curve NumbersTime Of Concentration ............................... 4 TimeOf Concentration.................................................................................................. 5 Intensity -Duration Curves Calculation SheetRainFall Depth ....................................... 6 RainFallDepth.............................................................................................................. 7 Valley Area Isohyetals 10 Years - 1 Hour.................................................................... 8 Valley Area Isohyetals 100 Years - 1 Hour.................................................................. 9 Hydrologic Soils Map:Southwest-A Area................................................................... 10 Rainfall— Frequency: 100-year................................................................................... 11 Rainfall— Frequency: 100-year................................................................................... 12 Rainfall— Frequency: 25-year..................................................................................... 13 Rainfall— Frequency: 25-year..................................................................................... 14 Rainfall— Frequency: 10-year..................................................................................... 15 Rainfall— Frequency: 10-year..................................................................................... 16 AppendixSection........................................................................................................ 17 HydrologyMap................................................................................................. 18 Hydrology Report for Holland Development Lytle Creek Prepared by Fontana. California KHR Associates Rough Grading Hydrology Study for Holland Development Lytle Creek Fontana, California November 1, 2007 Introduction This report documents the results of a Hydrology Study (Rough Grading Stage) for Holland Development -Lytle Creek proposed mixed-use project in the City of Fontana, California. The purpose of the study was to identify and assess site hydrology and the design of drainage facilities to accommodate rainfall runoff in accordance with City of Fontana and San Bernardino Regional Water Quality Control Board ordinances and guidelines. Existing Conditions Holland Development -Lytle Creek Multi -Family proposed mixed-use project lies within the San Bernardino County jurisdiction. (See Figure 1). 8C O � I 1 s SUMMIT i -` 0 15500 16000 15600 � � `� M. `yF� JOE AV ittwo 0 WK AOei + y ROSE �� �uRr ! MUM � �idiOC. 2s ^�-� 'MrtJ.feN..� �TSTER f,... A. SITE _ AY CNAR-,-„)11 Av .: } ST M 1560 0 n pm" TR' A M y 4rdt rl N?I1 DR ALK �iL. G f ti PIW¢� �/✓/• U°R ncc t AC�QI A�M �-# o JUKL 1 r OVEN-= R N CI LM CENTER AV Tamp kam.�} i R c AV OtXK ST I o 15700 Ly # R FRONTAGE _ i 66 cTia ��yy,��,, i � HIGtp.AND 15800 AY i AV S H A A a $ '1901 ,KTUIRL AV31 LLF CIR CNHMN Figure 1 - Project Vicinity Map -1- ' Hydrology Report for Holland Development Lytle Creek Prepared by Fontana California KHR Associates ' The site is mostly vacant land, with the exception of some small structures and medium dense vegitation. Street frontages are unimproved and will require full improvements as ' a condition of approval for the proposed project. IProposed Project 1 6 1 L - I Holland Development proposes to construct a 248 unit apartment complex, associated parking garages, and open spaces in the City of Fontana, California. The rectangular shaped project site is 11.02 acres in size, and is bound by the 1-210 Freeway to the south, Sierra Lakes Parkway to the north, Lytle Creek Road to the west, and Maloof Avenue to the east. (See Figure 2) In the Rough Grading stage all structure pads will be graded along with temporary drainage ditches to navigate storm water run-off to an engineered desilting basin located at the lowest spot of the site. Figure 2 — Conceptual Site Plan -2- Hydrology Report for Holland Development Lytle Creek Prepared by Fontana, California KHR Associates Hydrology Study Guidelines For analysis purposes, the project site was divided into several drainage areas — areas where divided into approximately 2 acres or less in size. These drainage areas, along with the general direction of surface flows, are depicted on the Hydrology Map in the Appendix section of this report. Volume and flow rate calculations are also summarized on the Hydrology Map. The calculations were based on the following hydrology guidelines and assumptions: 1) The San Bernardino County Department of Public Works Hydrology Manual (December 2001) was used in calculating rainfall runoff. 2) All storm drains are private. 3) The project site is not within a burned or debris producing area, and therefore requires no special consideration for debris volumes, debris bulked flow, or watershed erosion. -3- ■■ ::: MEN ::::MI BASIS! 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UY■■i■■■■■■■simage Hydrology Report for Holland Development Lytle Creek Fontana, California Time Of Concentration Tel LIMITATIONS] L 100 1. Maximum length - 1000 Feet Tc 1000 90 2. MaximUn area - 10 Acres 900 e0 i 00070 1 6 Y 60 Soo V 700 too 7 50 N100 w 600 :0 � o � 10 . -to to s00 t3 n� ao 0 35 0 0. C '� if un 0lo ed = 12 25 n a ,� 13 g�a u ped� � �Z� Is m 16 � ly. 17 5 17 /AC) is lal 19 t t oved , • -KEY L -H -n -K -Tc' Zl s u o 25 PI Develop�►ent 130 9 80- Apartment 75- Mobile Home 30-0 ~ 8 83- Condominium GO -Single Family -5,000 ft 2 Lot 7 40- Single Family- 1/4 Acre Lot 35 20- Single Family -I Acre Lot 6 10 - Single Family -21/2 Acre Lot 100 40 FxqAAfF, 5 (1) L- sad, H -5.d, K- Sing le Family (5-7 Du/AQ Development, T012.6 min. 4 (2) L• 550', H- 5.0', K; Commercial Development, Tc -9.7 Iain. SAN BERNARDINO COUNTY TIME OF CONCENTRATION NOMOGRAPH HYDROLOGY MANUAL FOR INITIAL SUBAREA -5- 9M. _PM9 �m 9 FO-== IES =a =E: a-- E=E=i 992 2 EME 19 9 E =- 9 119 I D p 0 F A M-7 a I I - MM -41 IYAN " kI- -A E 0 0 A 19 a a a T11 ti R 1-1v pk- - �-- . .............. ZZ .. . ....... N N :11" to: m I ontologist" tfum lumm Tr zones 16111=1tT nnn ! limma" . ............... -1:4p Hydrology Report for Holland Development Lytle Creek Fontana, California RainFaii Depth _ © �� ju O 1 1 \ l I . 0 2 5 to 25 50 100 RETURN PERIOD IN YEARS MOTsa 1. Me WTERM101ATE RETURN PUMPS KW 10-VCAR 410100 -YEA* ON NOW VALUES FROM MAPS, TNEM CONOW I?INTS AND REM VALM FM OESHIM MTYRI PSOM FOR EXAMPLE GIVEN W -YEA* ONE NOUR•O.SS AMO 100-VEAN CK $#OUR •1.W, ZS-T6AR ONE NOUR •I.W. RSFERENCI•NOAA ATLAS S• VOLUMI =-CAL.,IOTS RAINFALL DEPTH VERSUS SAN BERNARDINO COUNTY RETURN PERIOD FOR HYDROLOGY MANUAL PARTIAL DURATION SERIES D-7 -7- FIGURE 0-2 Hydrology Report for Holland Development Lytle Creek Prepared by Fontana California KHR Associates Valley Area Isohyetals 10 Years - 1 Hour T4N Ll — R W r R W I 4W R2W - - - - Y- - RIW"t RIE (• R2[ TT - - �- _ _ ___ — g-1 � jjj-M,, •. .�,...le. , r_ ! T3N - - - — _ _ T SysAr.— — — I I I I I ,r a ,. I M• - I • • , . ' � , LT � _ _ S L� - - - — - I — .-j �.,r BE T2N L -r•• LZ aft ji - 'nit — _ — — - - • •• . .r -tTN 1.4 r - 14 �--/ \.T• ., ` PROJECT SITE t1, h �: \7 Mme•. •••I ' � 1 ] �'."�'-"'J' � .l -I � �' - -' '• - � .L M - _ M !{ �•• y• TIC,' 4Lr, i t 7 t K rt+r• —' ra -' S' `�- T= \ ' r I,,;.. T IN AL Pt.allo QLANNOW TIS •' •• j ••~ n C TON ..Y ' - _ _ _ - _ _ — - - -� 7� 1 _ >� `-I - -. . _ _ a •+ - 4 - -- - � • _ RIE =. R E T2s ` — -_ - - - - - - - -- -� - - -' - - � - - _ �..« �; 7 - I RSIDE oA ~ ..• • ..• •. (� yr" R4W i' ' I T R3 R2W \ ioe RI NAR 0100 RSWC VALLEY AREA i • ...,....; REDUCED DRAWING Tas _ __ I •f• :. •'•: �''�r.;• SCALE 1"64 MILES ISOMET," Y. - to YEAR 1 H" MNM " wj&&r. WLM BLAS a. fws 1• -"1 . --•! __ t #!r'%.` - - - _ -- - -- • SAN BERNARDINO COUNTY A 7.0 •'• - , ' i•JtsW I 1 Riw .••• Rs HYDROLOGY MANUALcj ,sol,N i PR9CI•iTAT10N (INCH[!) a+sa ►•t Na •"•A •'• •...........................• Inas fear wR•r it I Hydrology Report for Holland Development Lytle Creek Prepared by Fontana, California KHR Associates Valley Area Isohyetals 100 Years - 1 Hour 0-12 FIGURE 9-4 lu Hydrology Report for Holland Development Lytle Creek Prepared by Fontana, California KHR Associates Hydrologic Soils Map:Southwest-A Area I "IL 4~ Mummy • M0. 0~ sclumT" ""'""""0`""""'"" 80UMMOF406AM Sft*ft SCALE REDUCIM BY 1/2 HYDROLOGIC SOLS GROUP MAP SAN BERNARDINO COUNTY FOR HYDROLOGY MANUAL SOUTHWEST -A AREA xo[x MAP FIGURE C-13 -10- Hydrology Report for Holland Development Lytle Creek Prepared by Fontana, California KHR Associates Rainfall— Frequency: 100 -year -11- -®-11111■------ -_--®-_®` Er i. -®-11111■------ ----®-_® . -®-llll------®-----®-®® -®-lllllllll'-----------®--® -11- Hydrology Report for Holland Development Lytle Creek Prepared by Fontana. California KHR Associates Rainfall- Frequency: 100 -year 100 -year storm 1-h our rainfall (in)= 1.4 Slope= -0.6 CN= 93 Natural Cover: Barren AMC III b= 15.5 Node Area At FA Soil Dev A, A a, a F Fm F, Length H Slope V t. 4 ". Notes No. No. (ac) (ac) type type (ac) (ac) (inthr) (inthr) avg (ft) (ft) OtIft) {fps) (min) (min) (inlhr) (cfs) 13 0.44 0.44 A Und. 0.04 0.40 0.10 0.90 0.18 0.16 0.16 207 4.1 0.020 9.0 4.1 1.58 Initial Area 0.44 9.0 1.58 Stream Summary 1.89 0.16 11.5 4.1 6.06 Confluence of 101112 and 13 - Case 2a 1.89 11.5 6.06 Stream Summary 14 0.31 0.31 A Und. 0.03 0.28 0.10 0.90 0.18 0.16 0.16 185 1.9 0.010 10.5 3.8 1.01 Initial Area 0.31 10.5 1.01 Stream Summary 2.20 0.16 11.5 4.1 7.17 Confluence of 10111213 and 14 - Case 2a 2.20 11.5 7.17 Stream Summary 15 0.26 0.26 A Und. 0.03 0.23 0.10 0.90 1 0.18 0.16 0.16 173 1.7 0.010 10.0 3.9 0.87 Initial Area 0.26 10.0 0.87 Stream Summary 2.46 0.16 11.5 4.1 8.10 Confluence of 1011121314 and 15 - Case 2a 2.46 11.5 8.10 Stream Summary 16 027 0.27 A Und. 0.03 0.24 0.10 0.90 0.18 1 0.16 0.16 175 1.8 0.010 10.0 3.9 0.91 Initial Area 0.27 10.0 0.91 Stream Summary 2.73 0.16 11.5 4.1 9.07 Confluence of 101112131415 and 16 - Case 2a 2.73 11.5 9.07 Stream Summary 17 0.79 0.79 A Und. 0.08 0.71 0.10 0.90 0.18 0.16 0.16 247 2.5 0.010 11.5 3.6 2.43 Initial Area 0.79 11.5 2.43 Stream Summary 3.52 0.16 11.5 4.1 11.50 Confluence of 10111213141516 and 17 - Case 1 3.52 11.5 11.50 Stream Summary 18 1.79 1.79 A Und. 0.18 1.61 0.10 0.90 0.18 0.16 0.16 343 6.9 0.020 11.5 3.6 5.51 Initial Area 1.79 11.5 5.51 Stream Summary 5.31 0.16 11.5 4.1 17.01 Confluence of 1011121314151617 and 18 - Case 1 5.31 1 11.5 17.01 Stream Summary 9.14 0.16 11.5 4.1 29.59 Confluence of Main 1 and Main 2 - Case 2b 9.14 11.5 29.59 Stream Summary 19 0.20 020 A Und. 0.02 0.18 0.10 0.90 0.18 0.16 0.16 163 1.6 0.010 9.9 3.9 0.68 j Initial Area 0.20 9.9 0.68 Stream Summary 9.34 0.16 1 11.5 4.1 30.31 Confluence of Main 12 and 19 - Case 2a 9.34 11.5 30.31 Stream Summary 20 0.45 0.45 A Und. 0.05 0.41 0.10 0.90 0.18 0.16 0.16 193 1.9 0.010 10.5 3.8 1.47 Initial Area 0.45 10.5 1.47 Stream Summary 9.79 0.16 11.5 4.1 31.92 Confluence of Main 1219 and 20 - Case 2a 9.79 11.5 31.92 Stream Summary -12- Hydrology Report for Holland Development Lytle Creek Prepared by Fontana, California KHR Associates Rainfall- Frequency: 25 -year 25 -year storm 1 -hour rainfall (in)= 1.2 Slope= -0.6 CN= 87 Natural Cover: Barren AMC II b= 15 Node Area At ZA soil Dev Ar A ar a F F,,, F,,, Length H Slope V t. Q 00 Notes No. No. ac) (ac) typa (ac) (Be) (infix) (-ft) avg (fl) (fl) 000 (fps) min (min) infir) (cfs) 1 1.02 1.02 A Und. 0.10 0.92 0.10 0.90 0.25 0.23 0.23 432 4.3 0.010 14.0 3.1 2.62 Initial Area 1.02 1,1 0 2.82 Steam Summary 2 0.37 0.37 A Und. 0.04 0.33 0.10 0.90 0.25 023 0.23 173 1.7 0.010 10.0 3.8 1.18 Initial Area 0.37 10.0 1.18 fSlresm Summary 1.39 023 14.0 3.8 3.57 Confluence of 1 and 2 - Case 2a 1.39 14.0 3.57 Steam Summary 3 0.60 0.60 A Und. 0.06 0.54 0.10 0.90 0.25 023 0.23 231 2.3 0.010 11.0 3.6 1.80 Initial Area 0.60 11.0 1.80 Steam Summary 1.99 023 14.0 3.8 5.48 Confluence of 12 and 3 - Case 2a 1.99 14.0 5.49 Steam Summary 4 0.71 0.71 A Und. 0.07 0.64 0.10 0.90 0.25 023 0.23 253 7.6 0.030 92 4.0 2.39 Initial Area 0.71 92 2.39 Steam Summary 2.70 0.23 14.0 4.0 7.75 Confluence of 123 and 4 - Case 2a 2.70 %0 7.75 Steam Summary 5 0.26 0.26 A Und. 0.03 023 0.10 0.90 0.25 023 0.23 175 1.8 0.010 10.0 3.8 0.83 Initial Area 0.29 10.0 0.33 Steam Summary 2.96 0.23 14.0 4.0 8.62 Confluence of 1234 and 5 - Case 2a 2.99 14.0 8.92 Steam Summary 6 0.70 0.70 A Und. 0.07 0.63 0.10 0.90 0.25 023 0.23 248 2.5 0.010 11.5 3.5 2.04 Initial Area 0.70 11.5 2.04 Steam Summary 3.66 023 14.0 4.0 10.98 Confluence of 12345 and 6 - Case 2a 3.99 %0 10.98 Steam Summary 7 0.59 0.59 A Und. 0.06 0.53 0.10 0.90 0.25 023 0.23 228 2.3 0.010 11.5 3.5 1.72 Initial Area 0.59 11.5 1.72 Steam Summary 4.25 023 14.0 4.0 12.96 Confluence of 123456 and 7 - Case 2a 4.25 14.0 12.99 Steam Summary 8 0.26 0.26 A Und_ 0.03 0.23 0.10 0.90 025 0.23 0.23 175 1.8 0.010 10.0 3.8 0.83 Initial Area 0.29 10.0 0.83 Steam Summary 4.51 0.23 14.0 4.0 13.83 Confluence of 1234567 and 8 - Case 2a 4.51 14.0 13.83 Steam Summary 9 0.15 0.15 A Und. 0.02 0.14 0.10 0.90 0.25 023 023 190 1.9 j 0.010 10.5 3.7 0.46 Initial Area 0.15 10.5 0.49 Steam Summary 4.66 0.23 14.0 4.0 14.34 Confluence of 12345678 and 9 - Case 2a 4.99 14.0 14.34 Steam Summary 10 0.59 0.59 A Und. 0.06 0.53 0.10 0.90 025 023 023 228 2.3 0.010 11.5 3.5 1.72 Initial Area 0.59 11.5 1.72 Steam Summary 11 0.27 0.27 A Und. 0.03 0.24 0.10 0.90 0.25 0.23 0.23 184 1.8 0.010 10.2 37 0.85 Initial Area 0.27 10.2 0.85 Steam Summwy 0.86 023 11.5 3.7 2.51 Confluence of 10 and 11 - Case 29 0.86 11.5 Z51 Steam Summary 12 0.64 0.64 A Und. 0.06 0.58 0.10 0.90 0.25 023 0.23 281 2.8 0.010 12.5 3.3 1.77 Irutial Area 0.94 12-5 1.77 Steam Summary 1.45 023 11.5 3.7 4.36 Confluence of 1011 and 12 - Case 2b 1.45 11.5 4.39 Steam Summary -13- Hydrology Report for Holland Development Lytle Creek Prepared by Fontana, California KHR Associates Rainfall— Frequency: 25 -year WE"A o(101112 and 13 -Case 29 PRIM MITTTA Confluence of 1011121314 and 15 - Case 2a of 101112131415 and 16 - Case 2a ��Ounfluence o(10111213141516 and 17 -Case I ��_Confiuwce o(1011121314151617 and 18- Case 1 MEN, -Oconfluence of Main land Main 2 -Case 2b Confluence of Main 12 and 19 - Case 29 I FYIConflLw" o(Main 1219 and 20 - Case 2a WE"A Hydrology Report for Holland Development Lytle Creek Prepared by Fontana California KHR Associates Rainfall— Frequency: 10 -year -15- I I _I_-_-_-------®--® I-IMMMMITIM ---lllllllllt--------------- -®-I_-----®----_®-®® IWITr TITTIMILM Confitwice of 12345678 and 9 - Case 2a -15- Hydrology Report for Holland Development Lytle Creek Prepared by Fontana, California KHR Associates Rainfall- Frequency: 10 -year 10 -year storm 1 -hour rainfall (in)-- 1 Slope= -0.6 CN= 87 Nalural Cover: Barren AMC II b= 12 Node Area At ZA Soil Dev Ar A a, a F FM F, Length H Slope V 4 4 Ip 4w Notes No. No. (ac) (ac) type type (ac) (ac) Orft) (infix) av9 (tt) (fl) (ft/ft) (fps) (min) (min) (MO (cfs) 13 0.44 0.44 A Und. 0.04 0.40 0.10 0.90 0.18 0.16 0.16 207 4.1 0.020 9.0 3.2 1.21 Initial Area 0.44 9.0 1.21 Steam Summary 1.89 0.16 11.5 3.2 4.63 Confluence of 101112 and 13 - Case 2a 1.89 11.5 4.93 Steam Summary 14 0.31 0.31 A Und. 0.03 0.28 0.10 0.90 0.18 0.16 0.16 185 1.9 0.010 10.5 2.9 0.77 Initial Area 0.31 10.5 0.77 Isirearn Summary 2.20 0.16 11.5 3.2 5.48 Confluence of 10111213 and 14 - Case 29 2.20 11.5 .4..48 Steam Summary 15 0.26 0.26 A Und. 0.03 0.23 0.10 0.90 0.18 0.16 0.16 173 1.7 0.010 10.0 3.0 0.67 Initial Area 0.26 10.0 0.67 Steam Summary 2.46 0.16 11.5 32 6.19 Confluence of 1011121314 and 15 - Case 2a 2.49 11.5 9.19 Steam Summary 16 0.27 0.27 A Und. 0.03 024 0.10 0.90 0.18 0.16 0.16 175 1.8 0.010 10.0 3.0 0.69 Initial Area 0.27 10.0 0.69 Steam Summary 2.73 0.16 11.5 3.2 6.93 Confluence of 101112131415 and 16 - Case 2a 2.73 11.5 6.93 Steam Summary 17 0.79 0.79 A Und. 0.08 0.71 0.10 0.90 0.18 0.16 0.16 247 2.5 0.010 11.5 2.8 1.86 Initial Area 0.79 11.5 1.86 Steam Summary 3.52 0.16 11.5 3.2 8.79 Confluence of 10111213141516 and 17 - Case 1 3.52 11.5 8.79 Steam Summary 18 1.79 1.79 A Und. 0.18 1.61 0.10 0.90 0.18 0.16 0.16 343 6.9 0.020 11.5 2.8 4.20 Initial Area 1.79 11.5 4.20 Steam Summary 5.31 0.16 11.5 3.2 12.99 Confluence of 1011121314151617 and 18 - Case 1 5.31 11.5 12.99 Steam Summary 9.14 0.16 11.5 32 22.61 Confluence of Main 1 and Man 2 - Case 2b 9.14 11.5 22.61 Steam Summary 19 0.20 0.20 A Und. 0.02 0.18 0.10 0.90 0.18 0.16 0.16 163 1.6 0.010 9.9 3.0 0.52 Initial Area 0.20 9.9 0.52 Steam Summary 9.34 0.16 11.5 3.2 23.16 Confluence of Main 12 and 19 - Case 2a 9.34 11.5 23.16 Stream Summary 20 0.45 0.45 A Und. 0.05 0.41 0.10 0.90 0.18 0.16 0.16 193 1.9 0.010 10.5 2.9 1.12 Initial Area 0.45 10.5 1.12 Steam Summary 9.79 0.16 11.5 3.2 24.39 Confluence of Main 1219 and 20 - Case 29 9.79 11.5 24.39 Steam Summary Hydrology Report for Holland Development Lytle Creek Prepared by Fontana. California KHR Associates Appendix Section -17-