HomeMy WebLinkAboutCUP 06-11B; PACIFIC RIDGE SCHOOL EXPANSION; DRAINAGE STUDY FOR PACIFIC RIDGE SCHOOL EXPANSION (PARKING LOT); 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: 6 (..,Jchel D Schweitzer RCE# 59658 Exp. 12-31-17
pate: 6/21/
Date Comments
03/16/16 Original
5/7/16 PC#1 No. 59658
rn PC#2 EXP. 6/21/16 Final \*
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I
TABLE OF CONTENTS
1.0 PROJECT DESCRIPTION .1
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
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.
VICINITY
CITY OF OCEANSIDE
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PACIFIC
OCEAN
CITY OF ENCINITAS
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 ufl 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-Development Areas and Flows
Area (ac) Qioo (cfs)
Basin I Pre- Post- Pre- Post-
Node Dev Dev Dev Dev
210/110 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 I I Runoff Coefflcient "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 L)
Permanent Open Space 0 0.20 0.25 0.30
Residential, 1.0 DU/A or less 10 0.27 0.32 0.36
Residential, 2.0 DU/A or less 20 0.34 0.38 0.42
Residential, 2.9 DU/A or less 25- 0.38 0.41 0.45
Residential, 4.3 DU/A or less 30 0.41 0.45 0.48
Residential, 7.3 DU/A or less 40 0.48 0.51 0.54
Residential, 10.9 DU/A or less 45 0.52 0.54 0.57
Residential, 14.5 DU/A or less 50 - 0.55 0.58 0.60
Residential, 24.0 DU/A or less 65 0.66 0.67 0.69
Residential, 43.0 DU/A or less 80 0.76 0.77 0.78
Neighborhood Commercial 80 0.76 0.77 0.78
General Commercial 85 0.80 0.80 0.81
Office Professional/Commercial 90 0.83 0.84 0.84
Limited Industrial 90 0.83 0.84 0.84
General Industrial 95 0.87 0.87 0.87
0.35
0.41
0.46
0.49
0.52
0.57
0.60
0.63
0.71
0.79
0.79
0.82
0.85
0.85
0.87
*The values associated with 01/o impervious may be used for direct calculation of the runoff coefficient as described in Section 3.1.2 (iepresenting 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).
DU/A = dwelling units per acre S /
NRCS = National Resources Conservation Service
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APPENDIX B
Pre-Development Hydrology Calculations
[_RECO1Ui COPY
Initial DJte
HYDROLOGY AND HYDRAULIC STUDY
CUP 06-11A .
DWG 445-2D
For
PACIFIC RIDGE SCHOOL
July 2, 2009
Prepared By:
Hofman Planning & Engineering
3152 Llonshead Avenue
Carlsbad, CA 92010
(760) 692-4100 m
RCE 58873
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Date
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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, Al = 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)] TC = [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 = 0.390(cFs) 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 = 0.01(Sq.Ft) Hydraulic grade line required at box inlet = 285.486(Ft.) Friction loss = 305.066(Ft.) Minor Friction loss = 0.000(Ft.) K-Factor = 0.000 Flow velocity = 27.85(Ft/s)
Travel time = 0.11 mm.
Time of concentration = 5.30 mm.
Adding area flow to channel
Rainfall intensity (I) = 7.109(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, Al = 0.400 M
C value = 0.570
Rainfall intensity = 7.109(In/Hr) for a 100.0 year storm Effective runoff coefficient used for total area
(Q=KCIA) is C = 0.570 CA = 0.085
subarea runoff = 0.444(cFS) for 0.110(Ac.)
Total runoff = 0.608(CFS) Total area = 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 'Z' of left channel bank = 2.000
slope or 'Z' of right channel bank = 2.000 Estimated mean flow rate at midpoint of channel = 0.993(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.)
Addinci 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) for a 100.0 year storm Effective runoff coefficient used for total area
(Q=KCIA) is C = 0.570 CA = 0.194
subarea runoff = 0.750(CFS) for 0.190(Ac.)
Total runoff = 1.358(CFS) Total area = 0.340(Ac.)
Depth of flow = 0.071(Ft.), Average velocity = 1.574(Ft/s)
Critical depth = 0.073(Ft.)
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
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 Manning's 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(m.)
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 1( 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(m.)
calculated individual pipe flow = 18.970(cFs)
Normal flow depth in pipe = 8.18(In.)
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)
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.))]A.385 *60(min/hr)
= 0.651 Minutes
Tt=[(11.9*0.0083A3)/( 0.87)]A.385= 0.65
Page
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.)
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 'V 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.)
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
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(In.)
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 velocity = 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
100 PRS100POST . out
Page 7
U 10 15 20
liMP (ulNuws)
EXHIBIT A
Pre and Post Development Maps
I -. 'f .,-- , - / -. / -
/ / EXIS11NG NODE ANALYSIS
_______ ______ / ,
r r \
____ _________-- ARiA A TMk, /100 In/Hr WOO cf - /f ,Yf, i, I / r " \\ - np cfl17sw - 7I7A N/A _JJA / ' ' 7 1,1/, I j I I I f J ->- :
___ ___ I — O.74 663 6.15 I/i//I /I//I 'I'i / 103 12 8.72 7T 5.52 177 ,//'/ 'in''//i/ ',/,iJ
-- 981 811 540 /// /,;'jj '11 /I (i ,-
1O I fl1-17 10I5 i3 527 2L: /,'" / 'i/ 'i/li 1/! 'if
---.- -.'---
"
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