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HomeMy WebLinkAboutCUP 06-11B; PACIFIC RIDGE SCHOOL EXPANSION; DRAINAGE STUDY; 2016-06-21DRAINAGE STUDY FOR CUP 06-11(B) Pacific Ridge School Expansion (Parking Lot) DWG 445-2G Carlsbad, California Engineer: SWS ENGINEERING. INC. 261 Autumn Drive, Suite 115 San Marcos, California 92069 P: 760-744-0011 F: 760-744-0046 PN: 15-046 Prepared by: A ichaelD. ____Date: 6/21/16 eitzer RCE# 59658 Exp. 12-31-17 Date Comments 03/16/16 Original 5/7/16 PC#1 o.5 9658 ' rn PC#2 31 6/21/16 Final EXP. /2/7 C:vi. / TABLE OF CONTENTS 1.0 PROJECT DESCRIPTION ................................................................................................. I 2.0 PURPOSE .........................................................................................................................2 3.0 METHODOLOGY...............................................................................................................2 4.0 HYDROLOGY....................................................................................................................2 4.1 Pre-Development Condition....................................................................................2 4.2 Post-Development Conditions................................................................................2 5.0 CONCLUSION...................................................................................................................3 APPENDICES Appendix A - Reference Charts Table 3-1 Runoff Coefficients for Urban Areas Figure 3-1 Intensity- Duration Design Chart Soil Hydrologic Groups Map 100 Year Rainfall Event - 6 Hours (P6 Rainfall Isopluvials) 100 Year Rainfall Event - 24 Hours (P24 Rainfall Isopluvials) Appendix B - Pre-Development Hydrology Calculations Appendix C - Post-Development Hydrology Calculations EXHIBITS Exhibit A - Pre and Post Development Hydrology Map VICINITY MAP CITY OF OCEANSIDE i TA I, OF I MARCOS CITY OF ENCINITAS 1.0 PROJECT DESCRIPTION The proposed project is the addition of 46 parking stalls at the southern end of the Pacific Ridge School. The project will add approximately 9,283 SF of impermeable area to the site. Pacific Ridge School 15-046 -2- City of Carlsbad 2.0 PURPOSE The purpose of this study is to determine the peak runoff rates and velocities for the pre- development and post-development conditions. Comparisons will be made at the same discharge points for each drainage basin affecting the site and adjacent properties. The adequacy of existing and proposed conveyance facilities affected by the project will be determined. 3.0 METHODOLOGY The Rational Method as outlined in the San Diego County Hydrology Manual, dated June 2003, was used to determine the runoff flow rate. The 100-year frequency storm event was analyzed to determine peak runoff rates discharging the site for both the existing and post-development condition. Soil type was determined to be type D from the Soil Hydrologic Groups map (see Appendix A). Where possible, the runoff coefficient "C" was determined by interpolating between categories in Table 3-1 (Appendix A) using the actual % impervious area. However, the CivilDesign hydrology software does not allow user-entered C-values for initial basins. Due to this limitation, the C-values for initial basins are based on the basin's actual percent impervious and closest matching land use category in Table 3-1 (Appendix A). An exhibit showing the pre-development impervious area is included in Appendix G. A Hydrology report (CUP 06-11(A) was prepared by Hofman Planing and Engineering (dated July 2, 2009) for the construction of Pacific Ridge School. Peak runoff rates, times of concentration, areas, and runoff coefficients are taken from this report and input at the upstream end of the storm drain system. Runoff coefficients, "C" are summarized as follows: Given the large amount of existing impermeable area on the site and the relative minor nature of the additional area no change to the C value in the Pre versus Post condition. 4.0 HYDROLOGY 4.1 Pre-Development Conditions In the area of the proposed work the site currently drains in the southerly direction down the access drive. A portion of the runoff drains directly out to El Feurte Street where it is picked up into the City's MS-4 system further south. A portion also dumps into two existing inlets on the site that tie directly into the City's MS-4 system. None of this runoff is currently detained or treated. Pacific Ridge School 15-046 -3 - City of Carlsbad 4.2 Post-Development Conditions The post development condition will add two inlets and two bioretention basins to the drainage system. Runoff will be a combination of channel flow in a gutter pan and sheet flow from the paved areas into each of the two bioretension basins from the new parking areas. The basins are designed to pond 1' prior to entering the 2x2 pre-cast inlet. This inlet will be tied into the existing onsite storm drain system. 5.0 CONCLUSION Development of the project site will increase the runoff from the pre-developed condition due to the reduction in the overall permeable' area. The proposed project will maintain, the flow patterns and drainage areas as in the pre-developed condition. The increase in runoff will be mitigated by the detention capabilities of the bioretention basin. Table I - Pre and Post-DeveloDment Areas and Flows Area (ac) Qioo (cfs) Basin! Pre- Post- Pre- Post- Node Dev Dev Dev Dev 210/110 i 9.6 9.6 18.97 20.36 1.39 REFERENCES County of San Diego Department of Public Works Flood Control Section. San Diego County Hydrology Manual. (2003) Pacific Ridge School 15-046 -4 - City of Carlsbad APPENDIX A Reference Charts San Diego County Hydrology Manual Section: 3 Date: June 2003 Page: 6 of 26 Table 3-1 RUNOFF COEFFICIENTS FOR URBAN AREAS Land Use Runoff Coefficient "C" Soil Type NRCS Elements County Elements % IMPEL A B C D Undisturbed Natural Terrain (Natural) Low Density Residential (LDR) Low Density Residential (LDR) Low Density Residential (LDR) Medium Density Residential (MDR) Medium Density Residential (MDR). Medium Density Residential (MDR) Medium Density Residential (MDR) High Density Residential (HDR) High Density Residential (HDR) Commercial/Industrial (N. Corn) Commercial/industrial (G. Corn) Commercial/Industrial (O.P. Corn) Commercial/industrial (Limited I.) Commercial/Industrial (General L) Permanent Open Space Residential, 1.0 DU/A or less Residential, 2.0 DU/A or less Residential, 2.9 DU/A or less Residential, 4.3 DU/A or less Residential, 7.3 DU/A or less Residential, 10.9 DU/A or less Residential, 14.5 DU/A or less Residential, 24.0 DU/A or less Residential, 43.0 DU/A or less Neighborhood Commercial General Commercial Office Professional/Commercial Limited Industrial General Industrial 0 0.20 0.25 0.30 0.35 10 0.27 0.32 0.36 0.41 20 0.34 0.38 0.42 0.46 25 0.38 0.41 0.45 0.49 30 0.41 0.45 0.48 0.52 40 0.48 0.51 0.54 0.57 45 0.52 0.54 0.57 0.60 50 0.55 0.58 0.60 0.63 65 0.66 0.67 0.69 0.71 80 0.76 0.77 0.78 0.79 80 0.76 0.77 0.78 0.79 85 0.80 0.80 0.81 0.82 90 0.83 0.84 0.84 0.85 90 0.83 0.84 0.84 0.85 95 0.87 0.87 *The values associated with 01/6 impervious may be used for direct calculation of the runoff coefficient as described in Section 3.1.2 (representing the pervious runoff coefficient, Cp, for the soil type), or for areas that will remain undisturbed in perpetuity. Justification must be given that the area will remain natural forever (e.g., the area is located in Cleveland National Forest). pu/A = dwelling units per acre NRCS = National Resources Conservation Service 3-6 APPENDIX B Pre-Development Hydrology Calculations A RECORIJ COPY Initial Ddte HYDROLOGY AND HYDRAULIC STUDY CUP 06-11A DWG 445-2D For PACIFIC RIDGE SCHOOL (t' owl-A July 2, 2009 Prepared By: Hofman Planning & Engineering 3152 Uonshead Avenue Carlsbad, CA 92010 (760) 692-4100 U to APn RCE 58873 Date Prepared by: )PC COP %-IIA APPENDIX C Post-Development Hydrology Calculations 100PRS100POST. Out San Diego County Rational Hydrology Program CIVILCADD/CIVILDESIGN Engineering Software, (c)1991-2006 Version 7.7 Rational method hydrology program based on San Diego County Flood Control Division 2003 hydrology manual Rational Hydrology Study Date: 06/10/16 ------------------------------------------------------------------------ PACIFIC RIDGE SCHOOL POST - DEVELOPMENT CONDITION - 100 YEAR STORM BASIN 100 PN 15-046 Hydrology Study Control Information Program License Serial Number 6144 Rational hydrology study storm event year is 100.0 English (in-lb) input data units used Map data precipitation entered: 6 hour, precipitation(inches) = 2.800 24 hour precipitation(inches) = 5.100 P6/P24 = 54.9% San Diego hydrology manual 'C' values used Process from Point/Station 101.000 to Point/Station 102.000 INITIAL AREA EVALUATION Decimal fraction soil group A = 0.000 Decimal fraction soil group B = 0.000 Decimal fraction soil group C = 0.000 Decimal fraction soil group D = 1.000 [MEDIUM DENSITY RESIDENTIAL ] (7.3 DU/A or Less ) Impervious value, Ai = 0.400 Sub-Area C Value = 0.570 Initial subarea total flow distance = 138.000(Ft.) Highest elevation = 248.800(Ft.) Lowest elevation = 239.500(Ft.) Elevation difference = 9.300(Ft.) Slope = 6.739 % Top of Initial Area Slope adjusted by User to 6.221 % INITIAL AREA TIME OF CONCENTRATION CALCULATIONS: The maximum overland flow distance is 100.00 (Ft) for the top area slope value of 6.22 %, in a development type of 7.3 DU/A or Less In Accordance With Figure 3-3 Initial Area Time of Concentration = 5.19 minutes IC = [1.8*(1.1_C)*distance(Ft.)A.5)/(% slopeA(1/3)] IC = [1.8*(1.1_0.5700)*( 100.000A.5)/( 6.221A(1/3)1= 5.19 Rainfall intensity (I) = 7.204(In/Hr) for a 100.0 year storm Effective runoff coefficient used for area (Q=KCIA) is C = 0.570 Subarea runoff = 0.164(CFS) Total initial stream area = 0.040(Ac.) Page 1 100PRS100POST. out Process from Point/Station 102.000 to Point/Station 103.000 IMPROVED CHANNEL TRAVEL TIME Covered channel upstream point elevation = 239.500(Ft.) Downstream point elevation = 219.920(Ft.) Channel length thru subarea = 182.000(Ft.) Channel base width = 0.140(Ft.) Slope or 'z' of left channel bank = 0.000 Slope or 'z' of right channel bank = 0.000 Estimated mean flow rate at midpoint of channel Manning's 'N' = 0.005 Maximum depth of channel = 0.100(Ft.) Flow(q) thru subarea = 0.390(CFs) Pressure flow condition in covered channel: Wetted perimeter = 0.48(Ft.) Flow area = Hydraulic grade line required at box inlet = Friction loss = 305.066(Ft.) Minor Friction loss = 0.000(Ft.) K-Factor Flow Velocity = 27.85(Ft/s) Travel time = 0.11 mm. Time of concentration = 5.30 mm. Adding area flow to channel 0. 390(CFS) 0.01(Sq.Ft) 285.486(Ft.) 0.000 Rainfall intensity (I) = 7.109(In/Hr) for a Decimal fraction soil group A = 0.000 Decimal fraction soil group B = 0.000 Decimal fraction soil group C = 0.000 Decimal fraction soil group D = 1.000 [MEDIUM DENSITY RESIDENTIAL (7.3 DU/A or Less ) Impervious value, Ai = 0.400 Sub-Area C Value = 0.570 Rainfall intensity = 7.109(In/Hr) for Effective runoff coefficient used for total (Q=KCIA) is C = 0.570 CA = 0.085 Subarea runoff = 0.444(CFS) for 0. Total runoff = 0.608(CFS) Total area 100.0 year storm 100.0 year storm area 110(Ac.) 0.150(Ac.) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 103.000 to Point/Station 104.000 IMPROVED CHANNEL TRAVEL TIME Upstream point elevation = 219.920(Ft.) Downstream point elevation = 219.570(Ft.) Channel length thru subarea = 10.000(Ft.) Channel base width = 12.000(Ft.) Slope or tZ' of left channel bank = 2.000 Slope or 'Z' of right channel bank = 2.000 Estimated mean flow rate at midpoint of channel = 0.993(cFS) Manning's 'N' = 0.030 Maximum depth of channel = 1.000(Ft.) Flow(q) thru subarea = 0.993(CFS) Depth of flow = 0.059(Ft.), Average velocity = 1.391(Ft/s) Channel flow top width = 12.236(Ft.) Flow Velocity = 1.39(Ft/s) Travel time = 0.12 mm. Time of concentration = 5.42 mm. critical depth = 0.060(Ft.) Adding area flow to channel Rainfall 'intensity (I) = 7.007(In/Hr) for a 100.0 year storm Decimal fraction soil group A = 0.000 Page 2 100PRS100POST. out Decimal fraction soil group B = 0.000 Decimal fraction soil group C = 0.000 Decimal fraction soil group D = 1.000 [MEDIUM DENSITY RESIDENTIAL (7.3 DU/A or Less ) Impervious value, Al = 0.400 Sub-Area C value = 0.570 Rainfall intensity = 7.007(In/Hr) Effective runoff coefficient used for (Q=KCIA) is C = 0.570 CA = 0.194 Subarea runoff = 0.750(CFS) for Total runoff = 1.358(CFS) Total Depth of flow = 0.071(Ft.), Average critical depth = 0.073(Ft.) for a 100.0 year storm total area 0.190(Ac.) area = 0.340(Ac.) velocity = 1.574(Ft/s) ++++++++++++++++++++++++++4-+++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 104.000 to Point/Station 105.000 PIPEFLOW TRAVEL TIME (Program estimated size) upstream point/station elevation = 209.500(Ft.) Downstream point/station elevation = 202.120(Ft.) Pipe length = 102.00(Ft.) Slope = 0.0724 Manningts N = 0.009 No. of pipes = 1 Required pipe flow = 1.358(CFS) Nearest computed pipe diameter = 6.00(In.) calculated individual pipe flow = 1.358(CFS) Normal flow depth in pipe = 3.43(In.) Flow top width inside pipe = 5.94(In.) critical depth could not be calculated. Pipe flow velocity = 11.70(Ft/s) Travel time through pipe = 0.15 mm. Time of concentration (TC) = 5.56 mm. Process from Point/Station 105.000 to Point/Station 105.000 CONFLUENCE OF MINOR STREAMS Along Main Stream number: 1 in normal stream number 1 Stream flow area = 0.340(Ac.) Runoff from this stream = 1.358(CFS) Time of concentration = 5.56 mm. Rainfall intensity = 6.888(In/Hr) Process from Point/Station 106.000 to Point/Station 106.000 USER DEFINED FLOW INFORMATION AT A POINT Decimal fraction soil group A = 0.000 Decimal fraction soil group B = 0.000 Decimal fraction soil group C = 0.000 Decimal fraction soil group 'D = 1.000 [MEDIUM DENSITY RESIDENTIAL ] (7.3 DU/A or Less ) Impervious value, Al = 0.400 Sub-Area C Value = 0.570 Rainfall intensity (I) = 4.758(In/Hr) for a 100.0 year storm user specified values are as follows: TC = 9.87 mm. Rain intensity = 4.76(In/Hr) Total area = 9.300(Ac.) Total runoff = 18.970(CFS) Page 3 100PRS100POST. Out +++++ +++++ ++ ++++ + ++++++++++ ++ ++++++++++ ++++ +++++++ + ++++++++ + Process from Point/station 106.000 to Point/Station 105.000 PIPEFLOW TRAVEL TIME (Program estimated size) upstream point/station elevation = 206.690(Ft.) Downstream point/station elevation = 202.120(Ft.) Pipe length = 22.00(Ft.) Slope = 0.2077 Manning's N = 0.009 No. of pipes = 1. Required pipe flow = 18.970(CFs) Nearest computed pipe diameter = 12.00(in.) calculated individual pipe flow = 18.970(cFS) Normal flow depth in pipe = 8.18(m.) Flow top width inside pipe = 11.18(m.) critical depth could not be calculated. Pipe flow velocity = 33.24(Ft/s) Travel time through pipe = 0.01 mm. Time of concentration (TC) = 9.88 mm. ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 105.000 to Point/Station 105.000 CONFLUENCE OF MINOR STREAMS Along Main Stream number: 1 in normal stream number 2 stream flow area = 9.300(Ac.) Runoff from this stream = 18.970(cFS) Time of concentration = 9.88 mm. Rainfall intensity = 4.754(In/Hr) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++4-+++++++++++ Process from Point/Station 107.000 to Point/Station 108.000 INITIAL AREA EVALUATION Decimal fraction soil group A = 0.000 Decimal fraction soil group B = 0.000 Decimal fraction soil group C = 0.000 Decimal fraction soil group D = 1.000 [MEDIUM DENSITY RESIDENTIAL ] (7.3 DU/A or Less ) Impervious value, Ai = 0.400 Sub-Area C value = 0.570 Initial subarea total flow distance = 124.000(Ft.) Highest elevation = 215.960(Ft.) Lowest elevation = 212.500(Ft.) Elevation difference = 3.460(Ft.) Slope = 2.790 % Top of Initial Area Slope adjusted by user to 1.980 % Bottom of Initial Area Slope adjusted by user to 1.980 % INITIAL AREA TIME OF CONCENTRATION CALCULATIONS: The maximum overland flow distance is 80.00 (Ft) for the top area slope value of 1.98 %, in a development type of 7.3 DU/ A or Less In Accordance with Figure 3-3 Initial Area Time of Concentration = 6.80 minutes TC = [1.8*(1.1_C)*distance(Ft.)A.5)/(% slopeA(1/3)] TC = [1.8*(1.1_0.5700)*( 80.000A.5)/( 1.980A(1/3)1= 6.80 The initial area total distance of 124.00 (Ft.) entered leaves a remaining distance of 44.00 (Ft.) Using Figure 3-4, the travel time for this distance is 0.65 minutes for a distance of 44.00 (Ft.) and a slope of 1.98 % with an elevation difference of 0.87(Ft.) from the end of the top area it = [11.9*length(Mi)A3)/(elevation change(Ft.))IA.385 *60(mjn/hr) = 0.651 Minutes Tt=[(11.9*0.0083A3)/( 0.87)]A.385= 0.65 Page 4 100PRs100PosT. out Total initial area Ti = 6.80 minutes from Figure 3-3 formula plus 0.65 minutes from the Figure 3-4 formula = 7.45 minutes Rainfall intensity (I) = 5.706(In/Hr) for a 100.0 year storm Effective runoff coefficient used for area (Q=KCIA) is C = 0.570 Subarea runoff = 0.276(CFS) Total initial stream area = 0.085(Ac.) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++4-+++++++++++ Process from Point/Station 108.000 to Point/Station 109.000 ** IMPROVED CHANNEL TRAVEL TIME Upstream point elevation = 214.720(Ft.) Downstream point elevation = 214.390(Ft.) Channel length thru subarea = 67.000(Ft.) Channel base width = 8.000(Ft.) Slope or 'Z' of left channel bank = 2.000 Slope or 'z' of right channel bank = 2.000 Estimated mean flow rate at midpoint of channel = 0.407(CFS) Manning's 'N' = 0.030 Maximum depth of channel = 1.000(Ft.) Flow(q) thru subarea = 0.407(CFS) Depth of flow = 0.079(Ft.), Average velocity = 0.630(Ft/s) channel flow top width = 8.316(Ft.) Flow velocity = 0.63(Ft/s) Travel time = 1.77 mm. Time of concentration = 9.22 mm. Critical depth = 0.043(Ft.) Adding area flow to channel Rainfall intensity (I) = 4.972(In/Hr) for a 100.0 year storm Decimal fraction soil group A = 0.000 Decimal fraction soil group B = 0.000 Decimal fraction soil group C = 0.000 Decimal fraction soil group D = 1.000 [MEDIUM DENSITY RESIDENTIAL ] (7.3 DU/A or Less ) Impervious value, Ai = 0.400 Sub -Area C value = 0.570 Rainfall intensity = 4.972(In/Hr) for a 100.0 year storm Effective runoff coefficient used for total area (Q=KcIA) is C = 0.570 CA = 0.094 Subarea runoff = 0.191(CFS) for 0.080(Ac.) Total runoff - 0.468(CFS) Total area = 0.165(Ac.) Depth of flow = 0.086(Ft.), Average velocity = 0.666(Ft/s) Critical depth = 0.047(Ft.) Process from Point/Station 109.000 to Point/Station 105.000 PIPEFLOW TRAVEL TIME (Program estimated size) Upstream point/station elevation = 205.900(Ft.) Downstream point/station elevation = 202.120(Ft.) Pipe length = 7.00(Ft.) Slope = 0.5400 Manning's N = 0.009 No. of pipes = 1 Required pipe flow = 0.468(CFS) Nearest computed pipe diameter = 3.00(In.) Calculated individual pipe flow = 0.468(CFS) Normal flow depth in pipe = 1.50(In.) Flow top width inside pipe = 3.00(In.) Critical depth could not be calculated. Pipe flow velocity = 19.10(Ft/s) Travel time through pipe = 0.01 mm. Time of concentration (TC) = 9.22 mm. Page 5 100PRS100POsT. Out +++ ++++++ + ++++++++++ + +++++++++++++++++++ ++ +++++ +++++++++ + Process from Point/Station 105.000 to Point/Station 105.000 CONFLUENCE OF MINOR STREAMS Along Main Stream number: 1 in normal stream number 3 Stream flow area = 0.165(Ac.) Runoff from this stream = 0.468(CFS) Time of concentration = 9.22 mm. Rainfall intensity = 4.970(In/Hr) summary of stream data: Stream Flow rate TC Rainfall Intensity. No. (CFS) (mm) (In/Hr) 1 1.358 5.56 6.888 2 18.970 9.88 4.754 3 0.468 9.22 . 4.970 Qmax(1) = 1.000 * 1.000 * .1.358) + 1.000 * 0.563 *. 18.970) + 1.000 * 0.603 * 0.468) + = 12.316 Qmax(2) = 0.690 * 1.000 * 1.358) + 1.000 * 1.000 * 18.970) + 0.957 * 1.000 * 0.468) + = 20.355 Qmax(3) = 0.722 * 1.000 * 1.358) + 1.000 * 0.934 * 18.970) + 1.000 * 1.000 * 0.468) + = 19.157 Total of 3 streams to confluence: Flow rates before confluence point: 1.358 18.970 0.468 Maximum flow rates at confluence using above data: 12.316 20.355 19.157 Area of streams before confluence: 0.340 9.300 0.165 Results of confluence: Total flow rate = 20.355(CFS) Time of concentration = 9.881 mm. Effective stream area after confluence = 9.805(Ac.) ++++4-+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 105.000 to Point/Station 100.000 PIPEFLOW TRAVEL TIME (Program estimated size) Upstream point/station elevation = 202.120(Ft.) Downstream point/station elevation = 189.520(Ft.) Pipe length = 60.00(Ft.) slope = 0.2100 Manning's N = 0.009 No. of pipes = 1 Required pipe flow = 20.355(cFS) Nearest computed pipe diameter = 12.00(m.) calculated individual pipe flow = 20.355(cFs) Normal flow depth in pipe = 8.60(In.) Flow top width. inside pipe = 10.81(m.) Critical depth could not be calculated. Pipe flow veloci.ty = 33.79(Ft/s) Travel time through pipe = 0.03 mm. Time of concentration (Tc) = . 9.91 mm. End of computations, total study area = 9.805 (Ac.) Page 6 100PRS100POST . out Page 7 0 5 10 15 20 liMP (ulNuws) EXHIBIT A Pre and Post Development Maps . . - - - EXISTING NODE ANALYSIS j II L -A&- V ___ . / CUP /17 1. lnll4r 2Lcc _'.TLa11 _L ±a 33 A;) 51Q 20.18 __ 5.27 22.22 H: 5.03 95 .55.69 O5 -T-O5 ___ 80_ __ 05 2.1 __ 9 453/ V .'2• - '.74 4.80 45.55 -z ;- 75 'z-. ------ i8 4.80 4.19 45.55 -- 45.5 e I - I '3 00 3 63 343 /1 (F - ' 7ii T I TA 32 4.95 -- 'V ' i _L... 2_ ...... :E 6.32 2.03 487 _71, 1-6 2C 1 I. S .5 5.56 4.86 16.98 207 17 ? 8 I.78 4.79 16.98 7/ 1I;.' j 9. /. r/ r 476 .J2 7 4,71 1848 1897 210 1/ Ifi-/ 2 4.75 18.97 - 2 1 'S 91,91 1520 360 475 1 _-7_ 35812 ?Jj ?t / - (i...) L._ \t ç I I on Ilk / V '• • I 1061 / BASIN I NODE 201 I/I \ \\ VV1 \\ \\\ \ \\\\\\\\\ 4O5OEG / //'/ '//'/ '/' Cr41 \ \ \ 1¼ I BASIN, 17 --ii 2 _: - / I T /////,5.79 ,, 79Ac ////\\\ N\ \\\\N / I: 1 ,, // \ \\ \\\\\\ \\\N I 01D~ ,O/ 3 =35/ y\\t\\\\ V 1O-YAR FR TI L N CO -! \\' 2323 \ \ I /21766 IE IF I/Il W !')I '(\ MBSIN BOAPY C \ \ \ \\ \ \ \ \ \\ \ \ \ \ \ \ \\ 1'c' / ' - / NODE \ 1f / / I t I IiJ i; \ ' / - C IN 3 / tX/sr 2 / 25422 FL AS - U.33 Ac 250M -- '- ' \ \ \ \ \ I 1/ 0.55 AC 2500FG C-.41 Ht 'i i i'\ \\OO\ ( F91 2,52. 00 AE NO NODE 109: r,,! 15 z?, 7 NODE 11h 0~ BAS 0 IE NOD 1 I mi~q I II" NO N 1. 21.2 -,,,Z , - I I -ii I 11 >1 PACIFIC RIDGE SCHOe%L >ITS- 2-_7,3. 1 0 04 AC - --- : i2385iE C=,-79 11 ii ji 15 I EXHIBIT 'A' --- -j /i\ 1142 L 1 I -: -' ( PMENT PRE-DEVELO INC. ,<7 245, 00 EG i HYDROLOGY MAP` uLR1\ LANDP \\Il • ula Parkway Suite 201 261 Autumn Drive, Suite 115 uav rc Temecula, CA 92592 San Marcos, CA 92069 a Z::7 SWS - r -ì - - F: 951-296-3407 F: 91-57-941 I F: 70-744-0011 F: 76-744-0046 DATE: Jun 13, 16 9:19am by: mike. schweitzer FILE: Z: \Pmjects\2O15\15-O45\POD\eports\HydroIogy\15-O46pREdwg