HYDROLOGY & HYDRAULICS

REPORT

Prepared for: PEACOCK HILL INC.

4641 INGRAHAM STREET SAN DIEGO, CA 92109

PROJECT:

PEACOCK HILL

LAKESIDE San Diego County

MPA 14-004

PREPARED BY:

P.O. Box 143

Bonsall, CA 92003 760 310 9408

August 10, 2016

SDC PDS RCVD 12-21-17 TM5598

Hydrology and Hydraulics Report County of San Diego

0.0  Declaration of Responsible Charge ........................................................ i 1.0  Project Information .................................................................................. ii 

1.1  Introduction to Site and Project Description ....................................................... ii 1.2  Existing Site Topography and Drainage Condition ............................................. iii 1.3  Proposed Topography and Drainage Condition ................................................. iii 

2.0  Hydrology and Hydraulic Calculations ................................................. iv 2.1  Method of Calculation ........................................................................................iv 2.2  Soil Type, Imperviousness, Selection of “C”....................................................... v 2.3  Summary Table of Q Values .............................................................................. v 

3.0  Detention Basin Sizing ........................................................................... vi 4.0  Report Summary ..................................................................................... vi 

4.1  Recommendations .............................................................................................vi  Appendices Appendix A

Existing Drainage Basin Map Proposed Drainage Basin Map Appendix B Hydrology Calculations

County of San Diego Hydrologic Tables and Figures Soil Map

Appendix C Confluence @ Junctions Calculations Hydrograh and Basin Calculations

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1.0 Project Information 1.1 Introduction to Site and Project Description

The site is located at 13586 Highway 8 Business Route, east of Los Coches Road in the community of Lakeside. The application is for a 68 unit multi-family residential development with an additional manager’s unit on a 4.4 acre site. The project shall also have private recreational building and swimming pool. Private streets and uncovered parking areas shall provide access and service to the residents.

Figure 1.1 Vicinity Map

This report will evaluate the Q100 for the existing condition and compare it to the Q100 for the proposed condition by using the Modified Rational Method and County of San Diego’s Hydrology Manual to evaluate peak flows.

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1.2 Existing Site Topography and Drainage Condition Topography of the site was provided by Canyon Land Surveying. Generally, the 4.4 acre rectangular shaped project slopes in the south and east direction toward Highway 8 Business Route which runs along the southeasterly boundary. A mobile home park is located along the north side of the site and self-storage complex is along the west side. Existing Offsite Drainage Facilities A 24” culvert exists at the southern property line within the Highway 8 Business District Right of Way. Runoff from the site enters this culvert via an existing grate inlet. Existing Onsite Drainage

The site area slopes in the south and east direction toward Highway 8 Business Route which runs along the southeasterly boundary. A mobile home park is located along the north side of the site and self-storage complex is along the west side. The current site has two drainage basins. The proposed development will not alter the historic drainage discharge points. The design is based on to the collection, treatment and detention (flow control) of the storm waters while maintaining the existing drainage patterns. Basin X & Y Basin X exists on the northeast corner of the property and is 0.94 acres. Runoff from Basin X is concentrated at the southerly point along Highway 80. The runoff then flows in the right of way westerly, toward the existing inlet of the 24” culvert where it is outlet south of Highway 80. Basin Y represents the majority of the site (3.85 acres). Runoff from Basin Y is also concentrated at the southerly point of the basin, along Highway 80. The runoff then flows in the right of way westerly, toward the existing inlet of the 24” culvert where it is outlet south of Highway 80. 1.3 Proposed Topography and Drainage Condition The proposed grading and drainage pattern will mimic the existing drainage condition and pattern. There will be 1 outlet point where runoff leaves the property, as there is the existing condition. The Outlet Point will remain in their original locations and will outlet at a non-erosive velocity. The site has been divided into 5 Basin Areas (A, B, C, D and E) with subareas defined by surface type. Each of these main basin areas have been calculated for 100 year runoff flows.

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The Basin areas also correspond to DMA areas, each with an appropriated sized Treatment Control Best Management Practice (TCBMP) sized for integrated management of the runoff. Runoff within the DMA areas of A, B, C, & E is collected within landscape runoff collection areas. Then runoff is then collected via an underground piping system and outlet to PCBMP A – Biofiltration with Partial Retention” which is sized to detain the 100 yr flood level storm. The Hydrograph and detention calculations are available in Appendix C. Runoff from the new street is collected via surface drainage and will be directed toward a rock infiltration swale designed to treat and roadside drainage. This swale will also outlet toward a grate inlet and flow into the 24” existing culvert. Infiltration testing has shown that there is infiltration properties within the native soil that provide treatment capacity. The overflow from the swale is directed to a curb outlet (S.D.R.S.D. D-25) which discharges to the street gutter. No below surface collection pipe system is proposed. 2.0 Hydrology Calculations 2.1 Method of Calculation This Hydraulics and Hydrology Report was prepared using the following Manual: Hydrology Manual, County of San Diego, 2003 The Rational Method was used to determine the 100 yr. Storm Q values. The Rational Method uses the following formula to establish 100 year flow:

Q= C I A where,

Q = the peak runoff in cubic feet per second

C = Runoff coefficient representing the ration of runoff to rainfall

I = time average intensity in inches per hour

A = Area of subbasin in acres

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2.2 Soil Type, Imperviousness, Selection of “C”

The native soil within the project site is classified as Hydrologic Group “C” according to the San Diego County Soils Interpretation Study maps. Group C soils are considered to have high runoff potential and moderate infiltration/percolation rates.

Southland Geotechnical Consultants has completed testing and analysis for the proposed site development.

Infiltration Testing has been done by and the soil has infiltrative properties.

The existing site is has some development totally approximately 4,356 sq. ft. of the 210,395 sq. ft. (2.1%). The existing slope of the property is greater than 10% in some areas. After the proposed development is complete, the impervious area of the site will 126,619 s.f.. The creation of pads will decrease the overall slope of the project and provide for larger times of concentration.

The runoff coefficient “C” will be based on the Hydrologic Soil Group “C” for both the existing and proposed condition. Calculations will be based on a runoff coefficient for Cexisting=0.30 & Cproposed = 0.60 for 14.5 units/acre (64/4.4=14.5) which is appropriate for this density.

See Appendices for County of San Diego Hydrology manual tables and figures.

2.3 Summary Table of Q Values ; Calculations were conducted for this project and are provided in the spreadsheet table in the Appendices.

PRE VS. POST SUMMARY

Node Basin Area Pre-

Basin Area Post-

Pre Development Discharge Q100

(cfs)

Post Development

Discharge Q100 (cfs)

Difference (cfs)

Mitigated (cfs)

Basin X & Y 4.79

8.4

Basin A, B, C, D, E 4.2 16.9 8.5 6.04

The difference between the pre and post condition is shown above. The detailed caclulations are provided in Appendices “A”. The overall site has an increase of +8.5 cfs for the Q(100) storm event. Each of the subbasins has a landscaped runoff

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collection area that will provide attenuation. The Biofiltration with Partial retention basin (PCBMP “A”) located near Highway 80 will provide 100-year mitigation for the increase in the post-development runoff. The basin provides mitigated flow rate is 6.04 cfs, which is less than the predevelopment conditions. The discussion of this integrated management and sizing of this basin is provided in Section 3.0.

3.0 Basin Sizing

In order to mitigate the additional storm water runoff created by the additional development on this site, the basin has been designed by using SDHM 3.0 continuous simulation model as well as hydrograph calculations provided in this report.

Overflow for the 100 year level storm is allowed via the 12” diameter riser. The basin will allow for a flow-rate of 6.04 cfs maximum which is below the level of the Q100 existing for the site. See the hydrograph calculations provided in Appendix C.

Each of the landscape collection areas provide throughout the property will provide for attenuation of the 100 flow level. The confluence calculations show the actual flow to the basin at the 100 year level. Inlet structures will be provided in each of the basins to outlet larger storm events and provide mitigation of the increased flow.

The PCBMP A has been design as an integrated device flow control at the 10-yr storm level and flow control for the 100 yr. level storm. An underground piping structure allows each of the basins A, B, C, & E to flow toward PCBMP “A” drainage pattern will allow all pad drainage to be treated and detained for mitigation of the 100-year flow within the PCBMP “A”.

Please see the SDHM 3.0 report located within the PDP SWQMP for the detailed modelling related to the flow control and pollutant control.

4.0 Report Summary

4.1 Recommendations This proposed development of this 4.4 acre site for 64 multifamily residences and a construction of a private road is in review for approval with regards to the County of San Diego’s subdivision ordinance.

In my professional opinion, the proposed project will not substantially alter the existing drainage pattern of the area. The project has been designed to maintain the historical

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drainage pattern and to mitigate the increase in flow and velocity caused by the development of this project. Due to these mitigation measures, there will be no increase in runoff to offsite parcels due to the development of this project.

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Appendices Appendices Appendix A

Existing Drainage Basin Map Proposed Drainage Basin Map Appendix B Hydrology Calculations

County of San Diego Hydrologic Tables and Figures Soil Map

Appendix C Confluence @ Junctions Calculations Hydrograh and Basin Calculations

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Appendix A

APPROVED BY DATEDESCRIPTIONNO.

COUNTY APPROVED CHANGES

DATUM

BENCH MARK

LOCATION

DESCRIPTION

ELEVATION

EN

GIN

EE

R'S

N

AM

E: d

k G

re

en

e C

on

su

ltin

g, In

c.

PH

ON

E N

O.: (7

60

) 3

10

-9

40

8

COUNTY OF SAN DIEGO

DEPARTMENT OF PUBLIC WORKS

PROPOSED HYDROLOGY MAP FOR:

CAL. COORD. INDEX:

SPECIAL USE PREMITNO.:

MAJOR USE PERMIT NO.:

TENTATIVE MAP NO.:

x

Appendix B

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SYSTEM AREA(AC) C

U/SELEVATION

(FT)

D/SELEVATION

(FT)

LENGTH(FT)

SLOPE(%)

P6(IN)

Ti from tab. 3-2

TC(MIN) 3-4

SUM OF TC(MIN)

I(IN/HR)

Q100(CFS)

Basin X 0.94 0.30 639.0 600.0 206 18.9 3.0 6.9 0.9 7.8 5.9 1.67Outfall 1 1.67

Basin Y 3.85 0.30 638.0 590.0 280 17.1 3.0 6.9 1.2 8.1 5.8 6.70Outfall 2 6.70

4.79 Total 8.37

PRE DEVELOPMENT CONDITION SUMMARY

SYSTEM AREA(AC) C Initial Slope LENGTH

(FT) Slope LENGTH(FT)

P6

(IN) Ti from 3-3 T from

3-3

SUM OF T(MIN)

I(IN/HR)

Q100(CFS)

OUTFALL 1

A-1.1 0.35 0.60 0.0 0.0 3.0 284 3.0 0.0 10.6 10.6 4.9 1.02 A-1.2 0.12 0.60 0.0 0.0 1.5 91 3.0 0.0 7.5 7.5 6.1 0.44 A-1.3 0.11 0.60 0.0 0.0 6.4 90 3.0 0.0 4.6 5.0 7.9 0.52 A-1.4 0.03 0.60 0.0 0.0 1.0 43 3.0 0.0 5.9 5.9 7.1 0.13 A-1.5 0.14 0.60 0.0 0.0 1.5 126 3.0 0.0 8.8 8.8 5.5 0.46 A-1.6 0.16 0.60 0.0 0.0 1.0 123 3.0 0.0 10.0 10.0 5.1 0.49A-2 0.16 0.60 0.0 0.0 12.0 163 3.0 0.0 5.1 5.1 7.8 0.75A-3 0.25 0.60 0.0 0.0 1.0 123 3.0 0.0 10.0 10.0 5.1 0.76

A-4 0.27 0.60 0.0 0.0 1.0 34 3.0 0.0 5.2 5.2 7.7 1.25 A-5 0.19 0.60 0.0 0.0 1.0 34 3.0 0.0 5.2 5.2 7.7 0.88 A-6 0.61 0.60 0.0 0.0 50.0 34 3.0 0.0 1.4 5.0 7.9 2.89 A-7 0.05 0.60 0.0 0.0 2.0 16 3.0 0.0 2.9 5.0 7.9 0.24 A-8 0.01 0.60 0.0 0.0 4.0 71 3.0 0.0 4.8 5.0 7.9 0.05 A-9 0.03 0.60 0.0 0.0 2.0 38 3.0 0.0 4.4 5.0 7.9 0.14

6.7 Total 10.01OUTFALL2

B-1 0.18 0.60 0.0 0.0 1.0 34 3.0 0.0 5.2 5.2 7.7 0.83Total 0.83

Outfall 3 C-1 0.19 0.60 0.0 0.0 1.0 32 3.0 0.0 5.1 5.1 7.8 0.89 C-2 0.05 0.60 0.0 0.0 2.0 34 3.0 0.0 4.2 5.0 7.9 0.24 C-3 0.02 0.60 0.0 0.0 4.0 34 3.0 0.0 3.3 5.0 7.9 0.09

Total 1.22Outfall 4

D-1 0.45 0.60 0.0 0.0 50.0 38 3.0 0.0 1.5 5.0 7.9 2.13D-2 0.27 0.60 0.0 0.0 1.0 39 3.0 0.0 5.6 5.6 7.3 1.19D-3 0.22 0.60 0.0 0.0 3.6 95 3.0 0.0 5.7 5.7 7.2 0.95

Total 4.28

E-1 0.11 0.60 0.0 0.0 1.0 26 3.0 0.0 4.6 5.0 7.9 0.52Total 0.52

Total 3.97 Grand Total 16.86

POST DEVELOPMENT CONDITION SUMMARY - 100 yr.

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Appendix C

User Name: Gary Date: 10-06-15 Project: KristinPeacock Time: 16:47:18 Scenario: Peocock Basin A Page: 1

RESERVOIR REPORT ================================================================================

Reservoir Number: 1 Name: Basin A Detention

[RATING CURVE LIMIT] Minimum Elevation = 588.00 (ft) Maximum Elevation = 596.00 (ft) Elevation Increment = 1.00 (ft)

[STAGE STORAGE INFORMATION] Storage Method: User-Defined Storage

Input Method: Area

Number Elevation Area Ave Area Volume Cumulative Volume (ft) (sq ft) (sq ft) (cu ft) (cu ft)

================================================================================ 1 592.00 0.00 0.00 0.00 0.002 593.00 3731.00 1865.50 1865.50 1865.503 594.00 4466.00 4098.50 4098.50 5964.004 595.00 5231.00 4848.50 4848.50 10812.505 596.00 6027.00 5629.00 5629.00 16441.506 597.00 6904.00 6465.50 6465.50 22907.007 598.00 7779.00 7341.50 7341.50 30248.50

[DISCHARGE INFORMATION] Structure Number: 1 Type:Name: Basin A Standpipe

Structure Number: 2 Type: Circular Orifice Name: HMP Orifice

[RESERVOIR STAGE STORAGE/DISCHARGE] -------------------------------------------------------------------------------- Elevation Stage Area Storage Discharge(ft) (ft) (sq ft) (cu ft) (cfs)================================================================================ 588.00 0.00 0.00 0.00 0.00589.00 1.00 0.00 0.00 0.00590.00 2.00 0.00 0.00 0.04591.00 3.00 0.00 0.00 0.07592.00 4.00 0.00 0.00 0.09593.00 5.00 3731.00 1865.50 0.11594.00 6.00 4466.00 5964.00 3.85595.00 7.00 5231.00 10812.50 6.25596.00 8.00 6027.00 16441.50 10.81

User Name: Gary Date: 10-06-15 Project: KristinPeacock Time: 16:47:18 Scenario: Peocock Basin A Page: 2 RESERVOIR REPORT ================================================================================ Maximum Storage = 16441.50 (cu ft) Maximum Discharge = 10.81 (cfs) User Name: Gary Date: 10-06-15 Project: KristinPeacock Time: 16:49:19 Scenario: Peocock Basin A Page: 1 OUTLET STRUCTURE LISTING ================================================================================ Number Name Type Defined -------------------------------------------------------------------------------- 1 Basin A Standpipe Stand Pipe Yes 2 HMP Orifice Orifice Yes User Name: Gary Date: 10-06-15 Project: KristinPeacock Time: 16:49:19 Scenario: Peocock Basin A Page: 2 OUTLET STRUCTURE REPORT ================================================================================ Structure Number : 1 Type : Stand Pipe Name : Basin A Standpipe [RATING CURVE LIMIT] Minimum Elevation = 588.00 (ft) Maximum Elevation = 596.00 (ft) Elevation Increment = 1.00 (ft) [STAND PIPE INFORMATION] ================================================================================ [ORIFICE INFORMATION] Diameter = 1.50 (ft) Crest Length = 4.71 (ft) Effective Crest Length = 4.71 (ft) Orifice Coefficient = 0.60 Fractional Open Area = 1.00 [ORIFICE EQUATION] Q = Co*A((2gh)/k)^0.5 [DEFINITIONS] Co = Orifice Coefficient A = Wetted Area, (sq ft)

[WEIR INFORMATION] Crest Elevation = 595.00 (ft) Weir Coefficient = 3.33 Exponential = 1.50 [WEIR EQUATION] Q = Cw * L * H^exp [DEFINITIONS] Cw = Weir Coefficient H = Headwater depth above inlet control section invert ft L = Crest lenght ft [OPTIONAL ORIFICE INFORMATION] ================================================================================ Structure Number : 1 Type : Rectangular Orifice [OPTIONAL ORIFICE INFORMATION] Height = 0.25 (ft) Width = 1.00 (ft) User Name: Gary Date: 10-06-15 Project: KristinPeacock Time: 16:49:19 Scenario: Peocock Basin A Page: 3 OUTLET STRUCTURE REPORT ================================================================================ Invert Elevation = 593.00 (ft) Orifice Coefficient = 0.60 Number of Openings = 2 [ORIFICE EQUATION] Q = Co*A((2gh)/k)^0.5 [DEFINITIONS] Co = Orifice Coefficient A = Wetted Area, (cfs) k = 1 Structure Number : 2 Type : Rectangular Orifice [OPTIONAL ORIFICE INFORMATION] Height = 0.25 (ft) Width = 1.00 (ft) Invert Elevation = 593.50 (ft) Orifice Coefficient = 0.60 Number of Openings = 2 [ORIFICE EQUATION] Q = Co*A((2gh)/k)^0.5 [DEFINITIONS] Co = Orifice Coefficient A = Wetted Area, (cfs) k = 1

[CULVERT INFORMATION] ================================================================================ Type : Circular Concrete - Square Edge with Headwall [OUTLET STRUCTURE INFORMATION] Diameter = 12.00 (in) Invert Elevation = 588.00 (ft) Pipe Length = 20.00 (ft) Slope = 0.03 Manning's n Value = 0.01 Orifice Coefficient = 0.60 Tailwater Elevation = 587.00 (ft) Number of Barrels = 1 [UNSUBMERGED EQUATION] H/Diam = Hc/Diam+K*(Q/(A*Diam^0.5))^M-0.5*S Coefficient K = 0.01 Coefficient M = 2.00 Q Maximum = 2.75 User Name: Gary Date: 10-06-15 Project: KristinPeacock Time: 16:49:19 Scenario: Peocock Basin A Page: 4 OUTLET STRUCTURE REPORT ================================================================================ [SUBMERGED EQUATION] H/Diam = c*(Q/(A*Diam^0.5))^2+Y-0.5*S Coefficient c = 0.04 Coefficient Y = 0.67 Q Minimum = 3.14 [DEFINITIONS] H = Headwater depth above inlet control section invert, (ft) Diam = Interior height of culvert barrel, (ft) Hc = Specific head at critical depth (dc+Vc^2/2g), (ft) Q = Discharge, (cfs) A = Full cross sectional area of culvert barrel, (sq ft) S = Culvert barrel slope, (ft/ft) [STAND PIPE STAGE VS. DISCHARGE] ================================================================================ Elevation Stage Weirs Orifices Stand Pipe Culvert Total (ft) (ft) (cfs) (cfs) (cfs) (cfs) (cfs) ================================================================================ 588.00 0.00 0.00 0.00 0.00 0.00 0.00 589.00 1.00 0.00 0.00 0.00 2.29 0.00 590.00 2.00 0.00 0.00 0.00 4.56 0.00 591.00 3.00 0.00 0.00 0.00 6.03 0.00 592.00 4.00 0.00 0.00 0.00 7.20 0.00 593.00 5.00 0.00 0.00 0.00 8.20 0.00 594.00 6.00 0.00 3.72 0.00 9.10 3.72 595.00 7.00 0.00 6.12 0.00 9.91 6.12 596.00 8.00 0.00 7.79 8.51 10.67 10.67 [WEIR STAGE VS. DISCHARGE]

================================================================================ Elevation Stage Weir 1 Weir 2 Weir 3 Weir 4 Total (ft) (ft) (cfs) (cfs) (cfs) (cfs) (cfs) ================================================================================ 588.00 0.00 0.00 0.00 0.00 0.00 0.00 589.00 1.00 0.00 0.00 0.00 0.00 0.00 590.00 2.00 0.00 0.00 0.00 0.00 0.00 591.00 3.00 0.00 0.00 0.00 0.00 0.00 592.00 4.00 0.00 0.00 0.00 0.00 0.00 593.00 5.00 0.00 0.00 0.00 0.00 0.00 594.00 6.00 0.00 0.00 0.00 0.00 0.00 595.00 7.00 0.00 0.00 0.00 0.00 0.00 596.00 8.00 0.00 0.00 0.00 0.00 0.00 [ORIFICE STAGE VS. DISCHARGE] ================================================================================ Elevation Stage Orifice 1 Orifice 2 Orifice 3 Orifice 4 Total User Name: Gary Date: 10-06-15 Project: KristinPeacock Time: 16:49:19 Scenario: Peocock Basin A Page: 5 OUTLET STRUCTURE REPORT ================================================================================ (ft) (ft) (cfs) (cfs) (cfs) (cfs) (cfs) ================================================================================ 588.00 0.00 0.00 0.00 0.00 0.00 0.00 589.00 1.00 0.00 0.00 0.00 0.00 0.00 590.00 2.00 0.00 0.00 0.00 0.00 0.00 591.00 3.00 0.00 0.00 0.00 0.00 0.00 592.00 4.00 0.00 0.00 0.00 0.00 0.00 593.00 5.00 0.00 0.00 0.00 0.00 0.00 594.00 6.00 2.25 1.47 0.00 0.00 3.72 595.00 7.00 3.30 2.82 0.00 0.00 6.12 596.00 8.00 4.08 3.71 0.00 0.00 7.79 User Name: Gary Date: 10-06-15 Project: KristinPeacock Time: 16:49:19 Scenario: Peocock Basin A Page: 6 OUTLET STRUCTURE REPORT ================================================================================ Structure Number : 2 Type : Circular Orifice Name : HMP Orifice [RATING CURVE LIMIT] Minimum Elevation = 588.00 (ft) Maximum Elevation = 596.00 (ft) Elevation Increment = 1.00 (ft) [OUTLET STRUCTURE INFORMATION] Diameter = 0.12 (ft) Orifice Coefficient = 0.60

Invert Elevation = 589.50 (ft) Number of Openings = 1 [CIRCULAR ORIFICE EQUATION] Q = Co*A((2gh)/k)^0.5 [DEFINITIONS] Co = Orifice Coefficient A = Wetted Area, (cfs) k = 1 [MAXIMUM DISCHARGE] Q = 0.15 (cfs) [ORIFICE STAGE VS. DISCHARGE] -------------------------------------------------------------------------------- Elevation (ft) Stage (ft) Discharge (cfs) ================================================================================ 588.00 0.00 0.00 589.00 1.00 0.00 590.00 2.00 0.04 591.00 3.00 0.07 592.00 4.00 0.09 593.00 5.00 0.11 594.00 6.00 0.12 595.00 7.00 0.13 596.00 8.00 0.15 User Name: Gary Date: 10-06-15 Project: KristinPeacock Time: 16:49:41 Scenario: Peocock Basin A Page: 1 FLOOD HYDROGRAPH REPORT ================================================================================ Number Name Type Defined -------------------------------------------------------------------------------- 1 PeCk-Basin A Inflow User Defined Yes 2 PeCk-Basin A Outflow Reservoir: Storage Yes User Name: Gary Date: 10-06-15 Project: KristinPeacock Time: 16:49:41 Scenario: Peocock Basin A Page: 2 FLOOD HYDROGRAPH REPORT ================================================================================ Hydrograph Number: 2 Name: PeCk-Basin A Outflow Type: Reservoir: Storage Indication [HYDROGRAPH INFORMATION] Peak Flow (Qp) = 3.61 (cfs) Time to Peak (Tp) = 260.00 (min) Time of Base (Tb) = 708.00 (min) Volume = 0.41 (ac-ft)

Time Step = 2.00 (min) Peak Elevation = 593.94 (ft) Detention Time = NA [RESERVOIR STRUCTURE INFORMATION] Number = 1 Name = Basin A Detention Storage Type = User-Defined Area Maximum Storage = 16441.50 (cu ft) Maximum Discharge = 10.81 (cfs) [INFLOW HYDROGRAPH INFORMATION] Number = 1 Name = PeCk-Basin A Inflow Peak Flow (Qp) = 6.05 (cfs) Time to Peak (Tp) = 252.00 (min) Time of Base (Tb) = 378.00 (min) Volume = 0.41 (ac-ft) Flow Multiplier = 1.00 [EQUATION] 0.5(I1+I2)dt + S1-0.5(O2)dt Where: I1 = Previous Inflow I2 = Current Inflow dt = Time increment S1 = Previous Storage S2 = Current Storage O1 = Previous Outflow O2 = Current Outflow A = 0.5 (I1+I2) dt B = S1 - 0.5 (O1) dt C = S2 + 0.5 (O2) dt User Name: Gary Date: 10-06-15 Project: KristinPeacock Time: 16:49:41 Scenario: Peocock Basin A Page: 3 FLOOD HYDROGRAPH REPORT ================================================================================ Computation of Reservoir Outflow Table of Storage Indication Method [The time interval is 2.00 min] -------------------------------------------------------------------------------- Intv Time Inflow A B C Outflow Storage Elev (min) (cfs) (cfs) (cfs) (cfs) (cfs) (cu ft) (ft) -------------------------------------------------------------------------------- 1 4.00 0.07 0.10 -0.03 -0.07 0.07 0.00 590.93 2 8.00 0.13 0.23 0.53 3.75 0.09 3.84 592.00 3 12.00 0.20 0.37 10.98 22.19 0.09 22.28 592.01 4 16.00 0.27 0.50 37.39 56.57 0.09 56.66 592.03 5 20.00 0.30 0.60 79.73 104.86 0.09 104.95 592.06 6 24.00 0.30 0.60 129.96 155.04 0.09 155.13 592.08 7 28.00 0.30 0.60 180.09 205.11 0.09 205.20 592.11 8 32.00 0.30 0.60 230.11 255.07 0.09 255.17 592.14

9 36.00 0.30 0.60 280.02 304.93 0.09 305.02 592.16 10 40.00 0.30 0.60 329.82 354.68 0.09 354.77 592.19 11 44.00 0.30 0.60 379.51 404.32 0.09 404.41 592.22 12 48.00 0.30 0.60 429.10 453.85 0.09 453.95 592.24 13 52.00 0.30 0.60 478.58 503.28 0.09 503.37 592.27 14 56.00 0.31 0.61 527.95 553.26 0.09 553.36 592.30 15 60.00 0.33 0.66 579.88 607.80 0.10 607.90 592.33 16 64.00 0.36 0.70 637.03 667.55 0.10 667.65 592.36 17 68.00 0.38 0.74 699.38 732.50 0.10 732.60 592.39 18 72.00 0.40 0.79 766.92 802.63 0.10 802.73 592.43 19 76.00 0.40 0.80 838.98 875.28 0.10 875.38 592.47 20 80.00 0.40 0.80 911.54 947.77 0.10 947.87 592.51 21 84.00 0.40 0.80 983.95 1020.10 0.10 1020.20 592.55 22 88.00 0.40 0.80 1056.21 1092.27 0.10 1092.37 592.59 23 92.00 0.40 0.80 1128.30 1164.29 0.10 1164.39 592.62 24 96.00 0.40 0.80 1200.25 1236.16 0.10 1236.26 592.66 25 100.00 0.40 0.80 1272.03 1307.87 0.10 1307.97 592.70 26 104.00 0.40 0.80 1343.66 1379.42 0.10 1379.52 592.74 27 108.00 0.40 0.80 1415.14 1450.82 0.10 1450.92 592.78 28 112.00 0.40 0.80 1486.46 1522.06 0.10 1522.17 592.82 29 116.00 0.40 0.80 1557.63 1593.15 0.10 1593.26 592.85 30 120.00 0.40 0.80 1628.64 1664.09 0.10 1664.19 592.89 31 124.00 0.40 0.80 1699.50 1734.87 0.11 1734.98 592.93 32 128.00 0.41 0.81 1770.21 1806.17 0.11 1806.28 592.97 33 132.00 0.43 0.86 1843.42 1881.11 0.12 1881.23 593.00 34 136.00 0.46 0.90 1917.25 1950.91 0.18 1951.09 593.02 35 140.00 0.48 0.94 1982.33 2011.76 0.24 2012.00 593.04 36 144.00 0.50 0.99 2039.39 2065.42 0.29 2065.71 593.05 37 148.00 0.52 1.03 2090.01 2113.31 0.33 2113.64 593.06 38 152.00 0.54 1.08 2135.45 2156.56 0.37 2156.94 593.07 39 156.00 0.57 1.12 2176.74 2196.09 0.41 2196.50 593.08 40 160.00 0.59 1.17 2214.70 2232.63 0.44 2233.07 593.09 User Name: Gary Date: 10-06-15 Project: KristinPeacock Time: 16:49:41 Scenario: Peocock Basin A Page: 4 FLOOD HYDROGRAPH REPORT ================================================================================ 41 164.00 0.61 1.21 2249.97 2266.77 0.47 2267.24 593.10 42 168.00 0.63 1.26 2283.09 2298.98 0.50 2299.48 593.11 43 172.00 0.66 1.30 2314.48 2329.64 0.53 2330.17 593.11 44 176.00 0.68 1.34 2344.48 2359.05 0.56 2359.61 593.12 45 180.00 0.70 1.39 2373.37 2387.46 0.58 2388.05 593.13 46 184.00 0.72 1.43 2401.36 2415.07 0.61 2415.68 593.13 47 188.00 0.74 1.48 2428.63 2442.04 0.63 2442.67 593.14 48 192.00 0.77 1.52 2455.32 2468.49 0.66 2469.15 593.15 49 196.00 0.79 1.57 2481.55 2494.52 0.68 2495.20 593.15 50 200.00 0.83 1.63 2507.41 2521.48 0.71 2522.19 593.16 51 204.00 0.90 1.77 2537.89 2556.37 0.74 2557.11 593.17 52 208.00 0.97 1.90 2576.73 2598.77 0.78 2599.54 593.18 53 212.00 1.03 2.03 2622.30 2647.19 0.82 2648.01 593.19 54 216.00 1.10 2.17 2673.27 2700.44 0.87 2701.31 593.20 55 220.00 1.14 2.27 2727.95 2755.13 0.92 2756.05 593.22 56 224.00 1.19 2.36 2782.01 2808.63 0.97 2809.60 593.23 57 228.00 1.23 2.44 2835.01 2861.18 1.02 2862.19 593.24 58 232.00 1.28 2.53 2887.15 2912.96 1.06 2914.03 593.26

59 236.00 1.83 3.13 2938.62 2992.87 1.14 2994.00 593.28 60 240.00 2.88 5.24 3101.48 3258.81 1.38 3260.19 593.34 61 244.00 3.94 7.35 3459.80 3699.91 1.78 3701.70 593.45 62 248.00 4.99 9.46 3975.10 4281.71 2.31 4284.02 593.59 63 252.00 6.05 11.57 4616.49 4976.51 2.95 4979.46 593.76 64 256.00 4.91 10.38 5296.63 5518.48 3.44 5521.92 593.89 65 260.00 3.76 8.09 5652.26 5707.11 3.61 5710.72 593.94 66 264.00 2.62 5.81 5691.22 5611.94 3.53 5615.47 593.91 67 268.00 1.47 3.52 5475.84 5288.83 3.23 5292.06 593.84 68 272.00 0.87 1.77 5056.19 4813.28 2.80 4816.07 593.72 69 276.00 0.80 1.63 4591.79 4389.50 2.41 4391.92 593.62 70 280.00 0.73 1.50 4204.43 4034.77 2.09 4036.86 593.53 71 284.00 0.67 1.37 3878.94 3735.49 1.81 3737.31 593.46 72 288.00 0.60 1.23 3603.15 3480.75 1.58 3482.33 593.39 73 292.00 0.58 1.17 3368.53 3266.70 1.39 3268.09 593.34 74 296.00 0.56 1.12 3174.17 3089.99 1.22 3091.21 593.30 75 300.00 0.53 1.08 3013.28 2943.27 1.09 2944.36 593.26 76 304.00 0.51 1.03 2879.27 2820.64 0.98 2821.62 593.23 77 308.00 0.49 0.99 2766.84 2717.36 0.88 2718.24 593.21 78 312.00 0.47 0.94 2671.75 2629.61 0.80 2630.42 593.19 79 316.00 0.44 0.90 2590.59 2554.35 0.74 2555.09 593.17 80 320.00 0.42 0.86 2520.61 2489.11 0.68 2489.79 593.15 81 324.00 0.40 0.81 2459.62 2431.92 0.62 2432.55 593.14 82 328.00 0.38 0.77 2405.84 2381.20 0.58 2381.78 593.13 83 332.00 0.36 0.72 2357.86 2335.67 0.54 2336.21 593.11 84 336.00 0.33 0.68 2314.53 2294.32 0.50 2294.81 593.10 85 340.00 0.31 0.63 2274.94 2256.31 0.46 2256.77 593.10 86 344.00 0.30 0.60 2238.35 2221.63 0.43 2222.06 593.09 87 348.00 0.30 0.60 2206.64 2193.20 0.41 2193.61 593.08 88 352.00 0.30 0.60 2181.16 2170.37 0.39 2170.76 593.07 User Name: Gary Date: 10-06-15 Project: KristinPeacock Time: 16:49:41 Scenario: Peocock Basin A Page: 5 FLOOD HYDROGRAPH REPORT ================================================================================ 89 356.00 0.30 0.60 2160.70 2152.04 0.37 2152.41 593.07 90 360.00 0.30 0.60 2144.27 2137.31 0.35 2137.67 593.07 91 364.00 0.23 0.50 2129.18 2118.10 0.34 2118.44 593.06 92 368.00 0.17 0.37 2104.39 2088.31 0.31 2088.62 593.05 93 372.00 0.10 0.23 2070.10 2050.00 0.28 2050.28 593.05 94 376.00 0.03 0.10 2028.20 2004.87 0.23 2005.11 593.03 95 380.00 0.00 0.00 1980.18 1956.15 0.19 1956.34 593.02 96 384.00 0.00 0.00 1934.61 1915.32 0.15 1915.47 593.01 97 388.00 0.00 0.00 1898.02 1882.52 0.12 1882.64 593.00 98 392.00 0.00 0.00 1868.63 1855.67 0.11 1855.78 592.99 99 396.00 0.00 0.00 1842.90 1830.15 0.11 1830.25 592.98 100 400.00 0.00 0.00 1817.41 1804.68 0.11 1804.78 592.97 101 404.00 0.00 0.00 1791.96 1779.26 0.11 1779.37 592.95 102 408.00 0.00 0.00 1766.57 1753.90 0.11 1754.00 592.94 103 412.00 0.00 0.00 1741.24 1728.59 0.11 1728.70 592.93 104 416.00 0.00 0.00 1715.96 1703.34 0.11 1703.45 592.91 105 420.00 0.00 0.00 1690.74 1678.14 0.10 1678.25 592.90 106 424.00 0.00 0.00 1665.57 1653.00 0.10 1653.11 592.89 107 428.00 0.00 0.00 1640.45 1627.91 0.10 1628.02 592.87 108 432.00 0.00 0.00 1615.39 1602.88 0.10 1602.98 592.86

109 436.00 0.00 0.00 1590.38 1577.90 0.10 1578.00 592.85 110 440.00 0.00 0.00 1565.43 1552.97 0.10 1553.08 592.83 111 444.00 0.00 0.00 1540.53 1528.10 0.10 1528.21 592.82 112 448.00 0.00 0.00 1515.69 1503.28 0.10 1503.39 592.81 113 452.00 0.00 0.00 1490.89 1478.52 0.10 1478.62 592.79 114 456.00 0.00 0.00 1466.16 1453.81 0.10 1453.91 592.78 115 460.00 0.00 0.00 1441.47 1429.15 0.10 1429.25 592.77 116 464.00 0.00 0.00 1416.84 1404.55 0.10 1404.65 592.75 117 468.00 0.00 0.00 1392.26 1380.00 0.10 1380.10 592.74 118 472.00 0.00 0.00 1367.74 1355.50 0.10 1355.60 592.73 119 476.00 0.00 0.00 1343.27 1331.05 0.10 1331.15 592.71 120 480.00 0.00 0.00 1318.85 1306.66 0.10 1306.76 592.70 121 484.00 0.00 0.00 1294.48 1282.32 0.10 1282.42 592.69 122 488.00 0.00 0.00 1270.17 1258.03 0.10 1258.13 592.67 123 492.00 0.00 0.00 1245.91 1233.80 0.10 1233.90 592.66 124 496.00 0.00 0.00 1221.70 1209.62 0.10 1209.72 592.65 125 500.00 0.00 0.00 1197.55 1185.49 0.10 1185.59 592.64 126 504.00 0.00 0.00 1173.44 1161.41 0.10 1161.51 592.62 127 508.00 0.00 0.00 1149.39 1137.39 0.10 1137.49 592.61 128 512.00 0.00 0.00 1125.39 1113.41 0.10 1113.51 592.60 129 516.00 0.00 0.00 1101.44 1089.49 0.10 1089.59 592.58 130 520.00 0.00 0.00 1077.55 1065.62 0.10 1065.72 592.57 131 524.00 0.00 0.00 1053.71 1041.80 0.10 1041.90 592.56 132 528.00 0.00 0.00 1029.91 1018.04 0.10 1018.13 592.55 133 532.00 0.00 0.00 1006.17 994.32 0.10 994.42 592.53 134 536.00 0.00 0.00 982.48 970.66 0.10 970.75 592.52 135 540.00 0.00 0.00 958.84 947.04 0.10 947.14 592.51 136 544.00 0.00 0.00 935.26 923.48 0.10 923.58 592.50 User Name: Gary Date: 10-06-15 Project: KristinPeacock Time: 16:49:41 Scenario: Peocock Basin A Page: 6 FLOOD HYDROGRAPH REPORT ================================================================================ 137 548.00 0.00 0.00 911.72 899.97 0.10 900.07 592.48 138 552.00 0.00 0.00 888.23 876.51 0.10 876.61 592.47 139 556.00 0.00 0.00 864.80 853.10 0.10 853.20 592.46 140 560.00 0.00 0.00 841.42 829.74 0.10 829.84 592.44 141 564.00 0.00 0.00 818.08 806.43 0.10 806.53 592.43 142 568.00 0.00 0.00 794.80 783.18 0.10 783.27 592.42 143 572.00 0.00 0.00 771.57 759.97 0.10 760.07 592.41 144 576.00 0.00 0.00 748.38 736.81 0.10 736.91 592.40 145 580.00 0.00 0.00 725.25 713.70 0.10 713.80 592.38 146 584.00 0.00 0.00 702.17 690.65 0.10 690.74 592.37 147 588.00 0.00 0.00 679.14 667.64 0.10 667.74 592.36 148 592.00 0.00 0.00 656.15 644.68 0.10 644.78 592.35 149 596.00 0.00 0.00 633.22 621.77 0.10 621.87 592.33 150 600.00 0.00 0.00 610.34 598.92 0.10 599.01 592.32 151 604.00 0.00 0.00 587.50 576.11 0.09 576.20 592.31 152 608.00 0.00 0.00 564.72 553.35 0.09 553.44 592.30 153 612.00 0.00 0.00 541.99 530.64 0.09 530.73 592.28 154 616.00 0.00 0.00 519.30 507.97 0.09 508.07 592.27 155 620.00 0.00 0.00 496.66 485.36 0.09 485.46 592.26 156 624.00 0.00 0.00 474.07 462.80 0.09 462.89 592.25 157 628.00 0.00 0.00 451.53 440.28 0.09 440.38 592.24 158 632.00 0.00 0.00 429.04 417.82 0.09 417.91 592.22

159 636.00 0.00 0.00 406.60 395.40 0.09 395.49 592.21 160 640.00 0.00 0.00 384.21 373.03 0.09 373.12 592.20 161 644.00 0.00 0.00 361.86 350.71 0.09 350.80 592.19 162 648.00 0.00 0.00 339.57 328.44 0.09 328.53 592.18 163 652.00 0.00 0.00 317.32 306.21 0.09 306.31 592.16 164 656.00 0.00 0.00 295.12 284.04 0.09 284.13 592.15 165 660.00 0.00 0.00 272.97 261.91 0.09 262.00 592.14 166 664.00 0.00 0.00 250.86 239.83 0.09 239.92 592.13 167 668.00 0.00 0.00 228.81 217.80 0.09 217.89 592.12 168 672.00 0.00 0.00 206.80 195.81 0.09 195.90 592.11 169 676.00 0.00 0.00 184.84 173.87 0.09 173.96 592.09 170 680.00 0.00 0.00 162.92 151.98 0.09 152.07 592.08 171 684.00 0.00 0.00 141.06 130.14 0.09 130.23 592.07 172 688.00 0.00 0.00 119.24 108.34 0.09 108.44 592.06 173 692.00 0.00 0.00 97.46 86.60 0.09 86.69 592.05 174 696.00 0.00 0.00 75.74 64.89 0.09 64.99 592.03 175 700.00 0.00 0.00 54.06 43.24 0.09 43.33 592.02 176 704.00 0.00 0.00 32.43 21.63 0.09 21.72 592.01 177 708.00 0.00 0.00 10.85 0.07 0.09 0.16 592.00 178 712.00 0.00 0.00 0.00 0.00 0.00 0.00 588.00 179 716.00 0.00 0.00 0.00 0.00 0.00 0.00 588.00 180 720.00 0.00 0.00 0.00 0.00 0.00 0.00 588.00