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HomeMy WebLinkAboutLytle Creek1 I Rough Grading Hydrology Study for � Holland Development Lytle Creek Fontana, California t January 3, 2008 1 1 1 1 1 1 1 1 1 1 1 1 1 V VIVJVLIIIV VI GIYVIIYGGf1J /JVfIYGl Vf1J /r LMIY IY Lf1J 4100 Newport Place Drive - Suite 200 Tel (949) 756 -6440 Newport Beach, California 92660 Fax (949) 756 -6444 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. �i James "awamurd, P. E. Date: January 3, 2008 Registered Civil Engineer No. C30560 0 g: E 0 4 0 TABLE OF CONTENTS ® Introduction ...................................................................................... ..............................1 ExistingConditions ........................................................................ ............................... 1 ProposedProject ............................................................................ ............................... 2 HydrologyStudy Guidelines .......................................................... ............................... 3 Infiltration Rate vs. SCS Curve NumbersTime Of Concentration ............................... 4 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 Rainfall— Frequency: 10 -year ...................................................... ............................... 16 AppendixSection ............................................ .............................17 HydrologyMap .................................................................. ............................... 18 e -ii- 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 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). d'p `Vp fig ! 1 Y �S - SUM IT .._._ _ _�. _ - - -- - AV 1500 �P4►? yER 0 15500 18000 Q � kl JOE AV d Ilk n .. . �..� LN p'..- _..... _ o__.. _. _... LN q0� ' Y 1 1LtON JLll /`may' T 7IIIW�` T \i PAR Fq l W LN a � r �k I M t J ROS�'NA�NC cuRr- R- w� � PARK c,__. MfR C t1 Ta ' LYSTER EAST ` AV !� _ AV ST _ �cuAxu,yr �t 1560 0 159C T FORTM LN &E: PALPH PINE w DR a'E g C A G 'a LEWIS C Q SUFF ISVEI LN � •1[10E ¢ 6 ` M�' 1 1A p t`3 S _5 F OfERLUX PL C�/NPLE a � ! CENTER AV I J � _ PKVY LN CARTER -- - - - - - -- m 19900 Tj WDOD LUCK ST I o 15700 AURTH SCI QlviAVE INL LJi � K w FONT WA rI; S PR4K -.... U FRONTAGE r CLTAT y HIGHLAND 15800 AV 4 Al � Ar 'S Av S H G A A .'_ Z L690U y SKVIARK AV y y Q it' AV RCUN 4.. 3 - ._ ` GIR GRUHNI AY ¢� 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 vegetation. Street frontages are unimproved and will require full improvements as a condition of approval for the proposed project. Proposed Project 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. LYTLE CREEK ROAD ``1 AA A Z I 1 A MALOOF AVENUE 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. r �r -3- i A mrimm■■ ■f1 lNIMIi■IN■ !MINI■! ■■■ ■N■i■■■■■ ■■■■■m■■!■ ■ra■ ■ ■■WW■ OMENS ■i ■ ■m■■ ■wi ■ ■■Ii■ ■■ ■■t■■IO■■ !! ■ ■ ■■lI K K�% mum NI i�■n n`i ommowxmwmmm ■i ■ ■ ■■ ■Nile' �r� :� MEN REP' !■■■!■ i■ ■f l w■W.■NIw■■■•.NINWsw ASO■ NINA! sum M OEM M Allor, 1� =:smumw, :::l:C:: �e �r Aw ems/ w »r �r w Hydrology Report for Holland Development Lytle Creek Fontana California Time Of Concentration L 1000 900 800 700 a.-. Tc' 100 90 80 TO a 50 500 i 35 400 30 LIMITATIONSt 1. Maximum length • 1000 Feet 2. Maximum area = 10 Acres Q . ., U Y 300 O .. Q $ too $ wo .. `o »; 60 9 0 to/ rte ao c a. TIC A 6�_ 7 12 356 23 n o c ( Co �14 U aped ;s k $) 15 ,20 Cover to 8 x 16 c lyO 17 5 17 /AC) 0 18 S' J ., martial � � 19 � t 1 aved) . KEY 20 ~ L- H- Tc -K -Tc' C c 2� w 25 S 8 P1 Development 150 9 80- Apartment o 75- Mobile Home 30 8 65- Condominium 60- Singis Fan, y-5,000 ft Lot 7 40- Single Family -1/4 Acre Lot 35 20 Single Family -I Acre Lot 6 10 - Single Family -21/2 Acre Lot 100 40 EXAMPLE 5 ( I ) L2 550', Hn5.6, Kit Sing is Family (5- DWAC) Development, Tc =12.6 min. 4 (2) L- 550', H- 5.0', K= Commercial Development, T09.7 min. SAN BERNARDINO COUNTY TIME OF CONCENTRA NOMOGRAPH HYDROLOGY MANUAL FOR INITIAL SUBARI &I .......... ............... ... ... . ............... =N - UNZIM ME . ............ uss"Is 1 11MM9 a I n it K 'Moot No., I on 1: "Un"" ninu, " am ...... gaa.,.ffi ol munn: lift" a Im I mm: m""u Imu am u: R MU M " , al HU M., 4M .. stasoll, " I ffir ---- tin - :am a i n naug:Igmill --Ins full AlIIIfIN g1/1It1 ■1ll III If ISO to -- !u mum small VVIBI Ito" "a" ......... .. iiiii _` ------------- ................ Hip MM:=: UiE ..... ....... ............... .. ------------ ­-----­- ................ ... .............. E =z i E H_ ---------- ---------- .............. .......... 1 . INIMIN M ........... 11.11111" ang.losms m oo "M 011 '".0 a a, unmnii " I "' to IV! immmula ition 0 ... amw.... an I I'll IM ot w.all 111,1111im, n tyl!_T tlMHHMHMM ti n iii BERNARDINO (;U a ^d"_ 6 %of UAKIIIAI ,. do 4w arr 4ft err ,rl d@ MR M 40 air AM aM MI. ,. a� 49 ', 411 r Ie Ar ar Hydrology Report for Holland Development Lytle Creek Fontana California RainFall Depth 3.3 3.3 3 3 2.3 2.3 U) W 2 z FE 2 a 2 W O -k J U4 1.3 1.3 z Q 0: 1 1 0.5 0.5 0 0 2 5 10 25 50 t00 RETURN PERIOD IN YEARS NoTEs I. Ir" INTERMEDIATE RET WIN PERN)OS PLOT 10- 'HEAR AND 100 -YEAR ON 040M VAW[f FROM MAPS, TI1EM fAlI1KCT F?INV$ AND READ VALUE FOR OESIREC RETURN P11111101% FOR EXAMPLE GIVEN 10 -YEAR ON E 11 Wso.*S AMC 100 -YEAR ONE HOUR •I.60",23 -YEAR ONE HOUR 81.18 REfERENCEoNOAA ATLAS s, VOLUME =- CA1.., RAINFALL DEPTH VERSUS SAN OMNARDWO COUNTY RETURN PERIOD FOR HYDROLOGY MANUAL PARTIAL DURATION SERIES D -7 FIGURE D-2 -7- d Hydrology Report for Holland Development Lytle Creek Prepared by Fontana, California KHR Associates Valley Area Isohyetals 10 Years - 1 Hour ` L� I I R R6W r- r R i i - + F 4W i I ` ' 1 -+ 1 -- - - + -- - t- -r _ T4N - T- - W R2W RIW `'_ RIE I • R2E —1 — .f � — � — — t— ! — >— -• — — r • — -- �/f ' 1 T - -- •— T . — ao� � — -- — _ � ^— — .• `- ` ' — — -- I — - - � I � — T4N _ I I _ •;arir I "•'' - t --I r -1-` - - r - t -*' - � - - Le - •, ., �+` � - I , _ .s � '! y I I , I T3N — — - - - 4 t •' '�•�• o i 1• _ )• I A ' 6Y J I •� I I rte C � • — - - — — — `' EWP$,S)2 . .�•.. .. � T2N - - �j.. • — T — — � � � . .,. ,ir — — - — � -- •:;:.�' — I ' — • �' � +3�' • �� •• EIrM — — — — — — I - ME Ai \ S PROJECT SITE E h h Lt wow". TTW tT _ 1 — — — ` ' -- i - f t ` \\ �. f `, i 7 °- f - 1 ri ; — - -t - '" 1 a_ Y''t •• I I I — i Ll - - - — t `,i it . o _ Lsr- _ e r , . ' { on "A la '' — — - t , , f b [• .�E. • 'fi _ �— - T I N -- u • • / F••tid 'vim I t '._ - ! � + � J I ., fir. +� � �' --� "!( ��— I I r L 17 N 0 • ,h � ....3 �� � � t I r u. •r.•ro ~ - . - � - — i .i _I — biwo i - -- �• - — R • l FONT :` ..[.` �.� -• - a -- Or - TIS O T l0♦• C TON � T1 v i - .. Y ' s _ • '. •WM. • �,t!. J - - - - -- - - - - ' r M ` ;H - t -I -- r -. . _ .. � - � _ .- - - �' '1- - -, -- - � �. w , [ •t - - - -- • / � RIE � � � � R E ,r•�.. I T23 Walton". e __ I RSIDE - -+ y,. R4W •f R3 R2W \ 10o RI ! i•'s' - - - - AN NAR NO C N CT - - •. "" `4 : ' =_ RSW: REDUCED DRAWING VALLEY AREA ,T3s _ •`' ��' "''�• SCALE 1"-4 MILES Y,. - w `Howe �•_ ' - '- r �� _ ry'o SAN BERNARDINO COUNTY M "M .tOA,. P J►A RLAf t, If►3 ON V A Mllrfrff tv '• R 0W I 1 R '•• RB •'•.• HYDROLOGY MANUAL ` „••••�•••••• „•,••, �•�•••.•• / .. IfOLINf ►11[Cl/ITATION LINCHEfI WE WAA "A M6 f11t/L M0. 1 1J 1!f= f •t[f• .MIO-1 j N 1 M Hydrology Report for Holland Development Lytle Creek Prepared by Fontana, California KHR Associates Valley Area Isohyetals 100 Years - 1 Hour Nm PA Old 610! fA MEWWWWO F7 it dMOMW -i„ �� ' - • psi -lam,. :.�_�•i, ��"l, � . --..- Tell 1A FRI _.=, fill - ro pm ter► i _ �� _ ��d�'�-� '!�'��� ERSIDE 1 i'``� � REDUCED DRAWING .. YEAR I HOUR W - - • • sv 8-12 FIGURE 0-4 -9- Hydrology Report for Holland Development Lytle Creek Prepared by Fontana. California KHR Associates Hydrologic Soils Map:Southwest -A Area - .gas" J - - - -- -� SO L agar► wuNDARY zn A Sag. S~DLSNMArmw ,�y�:'�,��. SCALE 1 — '_' - -- BOWNSM Of00CATEa.o SCALE REDUCE BY 1/2 HYDROLOGIC SOILS GROUP MAP SAM s911MAJ1S NO C"W" SAN 6ERNARDINO COUNTY ___� FOR HYDROLOGY MANUAL -- - SOUTHWEST -A AREA NWX MAP C -26 F16URF C -10- Hydrology Report for Holland Development Lytle Creek Prepared by Fontana, California KHR Associates Rainfall— Frequency: 100 -year -11- � ���ii ii - ��������������iii���i� --- 1111 - - - - -- - ®- 1111111111----- ®--- - - ® - ®® • - --- 111.--------- - - - - -- - ®- 111.--------- - - ® - -® :.. --- 111.--------- - - - - -- - ®- 111■----- ®--- - - ® - ®® • - -- _111.--- ------ - - - - -- - ®- 111.-------- _ - - ® - -® .,: --- 111.-------- - - - - - -- - ®- 1111'----- ®--- - - ® - ®® • - ®- 111.--------- - - ® - -® .,: - ®- 111._-------- - - ® - -® --- 111.--------- - - - - -- - ®- 1111,--------- - - ® - -® '. --- 111.--------- - - - - -- 1. . -®- 1111'------- - - - - ®- --- 111.-------- - - - - -- - ®- 111.----- ®---- - ® -_ ®� • '. _ • 1 : • - ®- 1111'------- - - - - ®- ® - -11- Hydrology Report for Holland Development Lytle Creek Prepared by Fontana, California KHR Associates Rainfall- Frequency: 100 -year 100 -year storm 1-hour rainfall (in)= 1.4 Slope= -0.6 CN= 93 Natural Cover: Barren AMC III b= 15.5 Node Area A t ZA Soil Dev A, A a, a F F,,, F m Length H Slope 77T 7 f Ir. Q,. Notes No. No. (ac) (ac) type type (ac) (ac) (in/hr) (in/hr) avg (ft) I (ft) (fUft) (fps) (min) (min) (in/hr) (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 1 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 0.18 0.16 0.16 173 1.7 0.010 10.0 3.9 0.87 Initial Area 0.26 1 1 1 1 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 0.27 0.27 A Und. 0.03 014 0.10 0.90 0.18 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 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 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 3.9 0.68 Initial Area 0.20 9.9 0.68 Stream Summary 9.34 0.16 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 1 4.1 1 31.92 Confluence of Main 1219 and 20 - Case 2a 9.79 1 11.5 1 1 1 31.92 ISIream Summary -12- Hydrology Report for Holland Development Lytle Creek Prepared by Fontana, California KHR Associates Rainfall- Frequency: 25 -year 25 leer storm 1-hour rainfall (in)= 1.2 Slope= -0.6 CN= 87 Natural Coven Barren AMC 11 b= 15 Node Area A t IA Soil Dev A, A a, a F F,,, F, Length H Slope V t, Q I C6 Notes No. No. (ac) (ac) type type (ac) (ac) (in/hr) (in/hr) avg (ft) (fl) (tuft) (fps) (min (min) (in/hr) (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 14,0 2.92 Stream 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 Stream Summa 1.39 023 14.0 3.8 3.57 Confluence of 1 and 2 - Case 2a 1 14.0 3.57 Steam Summary 3 0.60 0.60 A Und. 0.06 0.54 0.10 0.90 025 023 0.23 231 2.3 0.010 11.0 3.6 1.80 1 1nitial Area 0.90 11.0 1.80 Steam Summa 1.99 023 14.0 3.8 5.48 Confluence of 12 and 3 - Case 2a 1 14.0 5.48 Stream Summa 4 0.71 0.71 A Und. 0.07 0.64 0.10 0.90 0.25 023 1 0.23 253 7.6 0.030 92 4.0 2.39 Initial Area 0.71 9.2 2.39 Stream Summa 2.70 023 14.0 4.0 7.75 Confluence of 123 and 4 - Case 2a 2.70 %0 7.75 Steam SLffnma 5 0.26 0.26 A Und. 0.03 0.23 0.10 0.90 0.25 023 0.23 175 1.8 0.010 10.0 3.8 0.83 Initial Area 0.26 10.0 0.83 Steam Summary 2.96 023 14.0 4.0 8.62 Confluence of 1234 and 5 - Case 2a 2.96 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 Summa 3.66 023 j 14.0 4.0 10.98 Confluence of 12345 and 6 - Case 2a 3.99 %0 10.98 Steam Summa 7 0.59 0.59 A Und. 0.06 0.53 0.10 0.90 0.25 0.23 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 0.25 0.23 0.23 175 1.8 0.010 10.0 3.8 0.83 Initial Area 0.26 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 0.23 190 1.9 0.010 10.5 3.7 0.46 Initial Area 0.15 10.5 0.49 Steam Summary 4.66 023 14.0 4.0 14.34 Confluence of 12345678 and 9 - Case 2a 4.66 14.0 14.34 Steam Summary 10 0.59 0.59 A Und. 0.06 0.53 0.10 0.90 0.25 023 023 228 2.3 0.010 11.5 3.5 1.72 Initial Area 0.59 11.5 1.72 Stream Summary 11 0.27 0.27 A Und. 0.03 024 0.10 0.90 0.25 023 0.23 184 1.8 0.010 10.2 3.7 0.85 Initial Area 0.27 10.2 0.85 Stream Summary 0.86 0.23 11.5 3.7 2.51 Confluence of 10 and 11 - Case 2a 0.89 11.5 2.51 Stream Summary 12 0.64 0.64 A Und. 0.06 0.58 010 0.90 0.25 023 0.23 281 2.8 0.010 12.5 3.3 1.77 Initial Area 0.64 12-5 1.77 Stream Summa 1.45 023 11.5 1 3.7 4.36 Confluence of 1011 and 12 - Case 2b 1.45 11.5 1 39 Steam Summary -13- 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 A EA Soil Dev A, A a, a F F. F, Length H Slope V t, Q I� Q Notes No. No. (ac) (ac) type type (ac) (ac) (inmr) (inlhr) av9 (ft) (ft) (ft/ft) (fps) (min) (min) (Who (cfs) 13 0.44 0.44 A Und. 0.04 0.40 0.10 0.90 0.25 0.23 0.23 207 4.1 0.020 9.0 4.0 1.50 Initial Area 0.44 9.0 1.50 Stream Summary 1.89 0.23 11.5 4.0 5.75 Confluence of 101112 and 13 - Case 2a 1.89 11.5 5.75 Stream Summary 14 0.31 0.31 A Und. 0.03 1 0.28 0.10 0.90 0.25 0.23 0.23 185 1.9 0.010 10.5 3.7 0.96 1 Initial Area 0.31 1 1 10.5 0.96 Stream Summary 2.20 023 11.5 4.0 6.80 Confluence of 10111213 and 14 - Case 2a 2.20 11.5 6.80 Stream Summary 15 0.26 0.26 A Und. 0.03 1 0.23 0.10 0.90 0.25 023 0.23 173 1.7 0.010 10.0 3.8 0.83 Initial Area 0.26 10.0 0.83 Steam Summary 2.46 0.23 1 11.5 4.0 7.69 Confluence o(10111 21314 and 15 - Case 2a 2.46 11.5 7.69 Stream Summary 16 0.27 0.27 A Und. 0.03 0.24 0.10 0.90 0.25 0.23 023 175 1.8 0.010 10.0 3.8 0.86 lrfial Area 0.27 1 10.0 0.86 Stream Summary 2.73 0.23 1 11.5 4.0 8.61 Confluence of 101112131415 and 16 - Case 2a 2.73 11.5 8.61 Stream Summary 17 0.79 0.79 A Und. 0.08 0.71 0.10 0.90 0.25 0.23 023 247 2.5 0.010 11.5 3.5 2.30 Initial Area 0.79 1 11.5 2.30 Stream Summary 3.52 0.23 1 11.5 4.0 10.91 Confluence of 10111213141516 and 17 - Case 1 3.52 11.5 10.91 Stream Summary 18 1.79 1.79 A Und. 0.18 1.61 0.10 0.90 0.25 0.23 0.23 343 6.9 0.020 11.5 3.5 5.22 Initial Area 1.79 11.5 5.22 Streem Summary 5.31 0.23 11.5 4.0 16.13 Confluence of 1011121314151617 and 18 - Case 1 5.31 11.5 16.13 Stream Summary 9.14 0.23 11.5 4.0 28.08 Confluence of Main 1 and Main 2 - Case 2b 9.14 11.5 28.08 Steam Summary 19 0.20 0.20 A Und. 1 0.02 0.18 0.10 0.90 0.25 0.23 1 023 163 1.6 0.010 9.9 3.8 0.64 1 Initial Area 0.20 9.9 0.64 Stream Summary 9.34 1 0.23 11.5 4.0 28.76 Confluence of Main 12 and 19 - Case 29 9.34 11.5 28.76 Stream Summ 20 0.45 0.45 A Und. 0.05 0.41 0.10 0.90 0.25 0.23 1 023 193 1.9 0.010 10.5 3.7 1.39 Initial Area 0.45 10.5 1.39 Stream Summary 9.79 0.23 11.5 4.0 30.29 Confluence of Main 1219 and 20 - Case 2a 9.79 1 1 1 11.5 1 3029 Stream Summary -14- Hydrology Report for Holland Development Lytle Creek Prepared by Fontana California KHR Associates Rainfall— Frequency: 10 -year -15- oo��a��allll��llll�� ® ®� ©�� ■0 ©av Confluence of 1 and 2 - Case 2a iConffuence of 12 and 3 - Case 2a Conflueme of 123 and 4 - Case 2a P :. of 123456 and 7 - Case 2a Confluence of 1234567 and 8 - Case 2a Confluence 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 Natural Cover: Barren AMC II b= 12 Node Area A t ZA Soil Dev A, A a, a F F, F Length H Slope V t c Q 10 Notes No. No. (ac) (ac) type type (ac) (ac) (in/hr) (inthr) avg (R) (R) (tuft) (fps) (min) (min) (Who (afs) 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 6,44 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 4.63 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 Stream Summary 2.20 0.16 11.5 3.2 5.48 Confluence of 10111213 and 14 - Case 2a 220 11.5 5.48 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 0,28 1 1 10.0 0.67 Steam Summary 2.46 0.16 11.5 3.2 6.19 Confluence of 1011121314 and 15 - Case 2a Y.46 11.5 &19 Steam Summary 16 0.27 0.27 A Und. 0.03 0.24 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 5.93 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 1 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 Stream Summary 9.34 1 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 1 11.5 3.2 24.39 Confluence of Main 1219 and 20 -Case 2a 6,79 1 1 1 1 11.5 24.39 Steam Summary