Report 2_Drainage.pdf

UPC 104697 – Fort Lee Entrance

General Description:

VDOT Central Office Hydraulics Section has prepared a drainage design and associated computations for the Route 36 (Oaklawn Boulevard) project located in Prince George County. The purpose of this project is to construct a new entrance to the Fort Lee military base. The drainage plans and computations address the hydraulic changes to the roadway and comply with all regulatory requirements. The proposed design criteria are shown within this section. A detailed description of the stormwater management plan for channel/flood protection and water quality compliance is shown in Appendix A and Appendix B respectively.

Existing Conditions:

The project site is located in Prince George County. The existing runoff currently drains via roadside ditches along Route 36 to an existing 24” pipe crossing. Runoff from this crossing outfalls to the Petersburg National Battlefield National Park Service property. Lee Avenue currently drains through an existing storm sewer system and outfalls to an existing roadside ditch to the east of the Fort Lee Entrance. The roadside ditch drains to a 36” concrete pipe which crosses Route 36 and outfalls. All runoff from the project ultimately outfalls to Harrison Branch. There are no wetlands or water quality structures located within the project limits. Drainage area maps are provided in Appendix F and I. Soil map is provided in Appendix J.

Proposed Drainage System:

The project will maintain the same general flow patterns. A storm sewer system and ditch alignment will be constructed with the new Fort Lee Entrance road. The storm sewer on Lee Avenue will drain to the existing roadside ditch and outfall to the same 36” concrete pipe. Curb and gutter will be added to the widened Route 36 west of the Fort Lee Entrance. A storm sewer system in this area will outfall to the National Park Service property at the same location. All runoff will still ultimately outfall to Harrison Branch. Drainage area maps are provided in Appendix F and I. Soil map is provided in Appendix J.

Erosion and Sediment Control (ESC):

This ESC Plan has been designed and prepared in accordance with the VDOT’s approved ESC & Stormwater Management (SWM) Program Standards and Specifications. A copy of the Certification Form will be included in this document at final plan submission.

Hydrology:

The Rational Method of calculating discharge is used exclusively on this project because all drainage areas are less than 200 acres in size. Drainage areas were calculated with the use of electronic survey and design data. Soil type in the general drainage area are mainly “Sandy loam” and Hydrologic Soil Group of Type A. soil in this group have low runoff potential when thoroughly wet. Soil report is provided in Appendix J. Drainage area maps are provided in Appendix F. Time of concentration calculation for the offsite drainage area is provided in Appendix I. Soil map is provided in Appendix J.

Inlet Design:

All inlets on this project were designed using 4” per hour rainfall intensity. Bypass flow was either 100% intercepted or captured in the subsequent downstream structure. Computations for the inlets are attached to this document.

Storm Sewer Design:

Pipe and pipe systems are designed to convey the 10-year storm event. Computations for the pipes are attached to this document. The proposed pipe design that crosses Route 36 involve replacing the current DI-7 inlets (in the median and along the roadside ditch) with junction box- with DI-7 top, design of curb and gutter with curb inlets (DI3A), a twin 24” pipes that run from roadside DI- 7 inlet to the median, a 200 ft storage 24” storage pipe along the median. The existing 24” pipe under the westbound lane of Route 36 will remain and act as an orifice for the storage pipe. A storage routing through the 200 ft 24” storage pipe was performed to contain the post-development runoff to pre-development level. Detailed calculation are documented in the LD-229 and LD-347 forms (Appendix D) as well as storage routing calculations (Appendix H). In general, flow through the existing and proposed 24” pipe systems under Route 36 is largely influenced by the head at the 18” pipe from the Park Property. Review of the elevation contours at the head of 18” existing pipe, along the roadside ditch, along the median show that there is sufficient storage that will attenuate the peak discharge. However, this analysis assume the peak discharge is conserved and are not reduced by the occurrence of flooding at a junction or inlet locations.

Ditch Design:

All ditches on the project were designed and sized based on criteria outlined in Chapter 7 of the VDOT Drainage Manual. The ditches on the project are designed to convey the 10-year discharge, and to resist erosion from the 2-year discharge. Computations for the ditches are attached to this document.

Hydraulic Design Software:

The design software utilized on this project includes:

GEOPAK & SUDA Drainage for Storm Sewer Pipe Analysis and Spread Calculation

PondPack for Pipe Storage Routing

Eaglepoint for SWM Pond Routing

LD-268 Ditch Calculations

Performance-Based Water Quality Spreadsheet

APPENDIX A:

Channel and Flood Protection

The water quantity (stream channel erosion and flooding) requirements for this project are governed by the technical criteria of Part IIC (9VAC25-870-97 and 9VAC25-870-98).

Outfall at Route 36 Sta. 28+25:

The outfall at Route 36 Sta. 28+25 meets the requirements of the 1% rule for flooding and stream channel erosion. The total project area draining to the outfall is 0.40 acres, while the total drainage area to the outfall is 47.86 acres, making the project area

0.86% of the total drainage area.

A map demonstrating compliance with the 1% rule can be found on the following page.

The water quantity (stream channel erosion and flooding) requirements for this project are governed by the technical criteria of Part IIC (9VAC25-870-97 and 9VAC25-870-98).

Outfall at Route 36 Sta. 28+25:

The outfall at Route 36 Sta. 28+25 meets the requirements of the 1% rule for flooding and stream channel erosion. The total project area draining to the outfall is 0.40 acres, while the total drainage area to the outfall is 47.86 acres, making the project area 0.40

= 0.84% of the total 46.66 drainage area. A map demonstrating compliance with the 1% rule can be found on the following page.

Total drainage area =

47.86 acres

Project disturbed area =

0.40 acres

(C) Copyright 2016, Trimble Navigation Limited, 2006-2017 TomTom

077° 21' 30.0000" W 077° 20' 60.0000" W 077° 20' 30.0000" W

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N

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N

.0

N

.0

N

.0

N

.0

N

SCALE 1:9028

0 1000 2000

Feet abiot.gemechu Text Box Total Drainage Area= 46.58 acres

Outfall at Route 36 Sta. 50+00:

For the outfall at Route 36 Sta. 50+00, the requirements of Minimum Standard-19 (MS-19) are met by reducing the discharge from the developed condition to below the existing peak discharge rates for the 2- and 10-year storms. The spreadsheet on the following page shows the increase in runoff for the developed condition for the 2-, 10-, and 100-year storms. An extended detention basin near the entrance to Fort Lee will be utilized to reduce the peak flow rate below existing conditions. Routing calculations for the extended detention basin can be found at the end of this document.

DA = 48.2619 acres DA = 48.2619 acres

Acres Acres

5.4006 8.2822

42.8613 39.9797

0.3671 0.4030

If= B / (Tc + D) E

Cf

Tc = 35 min. 1.00

Prince George County (10-year storm): 1.10

B = 53.51 1.20

D = 10.00 1.25

E = 0.74

B

(Tc + D)E

Qpre (10)= Cf * Cpre * If * A = = 56.69 cfs Q10 (inflow) = 11.42 cfs

Qpost (10)= Cf * Cpost * If * A = = 62.22 cfs Q10 (routed) = 4.71 cfs

Increase = 5.53 cfs Decrease = 6.71 cfs

If= B / (Tc + D) E

Cf

Tc = 35 min. 1.00

Prince George County (2-year storm): 1.10

B = 60.12 1.20

D = 11.50 1.25

E = 0.84

B

(Tc + D)E

Qpre (2)= Cf * Cpre * If * A = = 42.34 cfs Q2 (inflow) = 8.76 cfs

Qpost (2)= Cf * Cpost * If * A = = 46.48 cfs Q2 (routed) = 3.61 cfs

Increase = 4.13 cfs Decrease = 5.15 cfs

2, 5, and 10

Drainage Area Pre-development Drainage Area Post-development

Runoff Coefficient ("C") Runoff Coefficient ("C")

0.9 0.9

0.3 0.3

Weighted "C" = Weighted "C" =

Recurrence Interval (Years)

2, 5, and 10

If = = 53.51

= 3.20 in/hr(35 + 10.00) 0.74

1.00 * 0.3671 * 3.20 * 48.26

1.00 * 0.4030 * 3.20 * 48.26

Recurrence Interval (Years)

If = = 60.12

= 2.39 in/hr(35 + 11.50)0.84

1.00 * 0.3671 * 2.39 * 48.26

1.00 * 0.4030 * 2.39 * 48.26 abiot.gemechu Highlight abiot.gemechu Highlight abiot.gemechu Highlight

If= B / (Tc + D) E

Cf

Tc = 35 min. 1.00

Prince George County (100-year storm): 1.10

B = 34.71 1.20

D = 5.25 1.25

E = 0.55

B

(Tc + D) E

Qpre (100)= Cf * Cpre * If * A = = 100.74 cfs Q100 (inflow) = 19.43 cfs

Qpost (100)= Cf * Cpost * If * A = = 110.56 cfs Q100 (routed) = 13.32 cfs

Increase = 9.83 cfs Decrease = 6.11 cfs in/hr(35 + 10.00) 0.74

1.25 * 0.3671 * 4.55 * 48.26

1.25 * 0.4030 * 4.55 * 48.26

If = = 53.51

= 4.55

Recurrence Interval (Years)

2, 5, and 10

APPENDIX B:

Water Quality

The water quality requirements for this project are governed by the technical criteria of Part IIC

(9VAC25-870-96). Nutrient credits shall be purchased to meet the water quality requirements of the technical criteria. The total pollutant removal requirement for this project is 1.19 lb/year.

Calculations for the quantity of nutrient credits required can be found on the following page.

Date:

Check By:

County:

12.79 acres

= acres

= acres

= 5.58 acres other:

= acres

= acres

5.58 acres

43.63 %

16.00 %

STEP 2: Determine the avg. land cover condition (Iwatershed) or the exist. impervious cover (Iexist)

STEP 1: Determine the applicable area (A) and the post-developed impervious cover (Ipost).

structures parking lot roadway

(input description)

104697

RJW

WORKSHEET 1

Total =

Ipost = (total post-development impervious cover ÷ A) x 100 =

1. Average land cover condition (Iwatershed):

Iwatershed=

09/08/16

Iwatershed=

(input locality value or leave blank if one does not apply)

County Number:

PERFORMANCE-BASED WATER QUALITY CALCULATIONS

Prince George

If the locality has determined land cover conditions for individual watersheds within its jurisdiction, use the watershed specific value determined by the locality as Iwatershed.

(input description)

Applicable area (A) =

Post-development impervious cover:

Otherwise, use the Chesapeake Bay default value:

Version 8.14.15

Performance Based Water Quality

104697 Fort Lee Entrance

Project No.

Calc. By: VAB

County:

= acres

= acres

= 4.84 acres other:

= acres

= acres

4.84 acres

37.84 %

Ipost 43.63 % <= Iwatershed 16.00 %

Situation 1:

This consists of land development where the existing percent impervious cover

(Iexisting) is less than or equal to the average land cover condition (Iwatershed) and the proposed improvements will create a total percent impervious cover

(Ipost) which is less than or equal to the average land cover condition

(Iwatershed).

104697

RJW

WORKSHEET 1

Existing impervious cover:

Situation 1 Not Applicable

Iexisting = (total existing impervious cover ÷ A*) x 100 =

The site information determined in STEP 1 and STEP 2 provide enough information to determine the appropriate development situation under which the performance criteria will apply. The appropriate development situation will marked by an "X" except situation 4 that will require user input if it applies.

STEP 3: Determine the appropriate development situation.

* The applicable area (A) should be the same as used in STEP 1.

(input description)

Total =

(input description) parking lot roadway

County Number:

PERFORMANCE-BASED WATER QUALITY CALCULATIONS

Prince George

2. Existing impervious cover (Iexisting):

Determine the existing impervious cover of the development site if present.

structures

Version 8.14.15

Performance Based Water Quality

104697 Fort Lee Entrance

Project No.

Calc. By: VAB

09/08/16

County:

Iexisting 37.84 % <= Iwatershed 16.00 % ;and

Ipost 43.63 % > Iwatershed 16.00 %

X

Iexisting 37.84 % > Iwatershed 16.00 %

Worksheet 4 Not Applicable

Situation 2:

This consists of land development where the existing percent impervious cover

(Iexisting) is less than or equal to the average land cover condition (Iwatershed) and the proposed improvements will create a total percent impervious cover

(Ipost) which is greater than the average land cover condition (Iwatershed).

Situation 3: This consists of land development where the existing percent impervious cover

(Iexisting) is greater than the average land cover condition (Iwatershed).

Situation 4: This consists of land development where the existing percent impervious cover

(Iexisting) is served by an existing stormwater management BMP (s) that addresses water quality.

If the proposed development meets the criteria for development situation 1, then the low density development is considered to be the BMP and no pollutant removal is required. The calculation procedure for situation 1 stops here. If the proposed development meets the criteria for development situations 2,3, or 4, then proceed to STEP 4 on the appropriate worksheet.

Use Worksheet 3

Worksheet 2 Not Applicable

County Number: 74

PERFORMANCE-BASED WATER QUALITY CALCULATIONS

WORKSHEET 1

Prince George Version 8.14.15

Performance Based Water Quality

104697 Fort Lee Entrance

Project No. 104697

Calc. By: RJW

VAB

County:

12.79 acres

43.63 %

16.00 %

37.84 %

Iexisting 37.84 % > Iwatershed 16.00 %

37.84 %

12.79 acres

11.39

A =

Lpre(existing) = pounds per year

Iexisting =

A = existing site impervious cover (percent expressed in whole numbers) applicable area (acres)

SUMMARY OF SITUATION 3 CRITERIA: FROM CALCULATION PROCEDURE STEP 1 THRU STEP 3, WORKSHEET 1:

Iwatershed=

Applicable area (A) =

Ipost = (total post-development impervious cover ÷ A) x 100 =:

Iexisting = (total existing impervious cover ÷ A) x 100 =:

STEP 4: Determine the relative predevelopment pollutant load (Lpre).

Iexisting =

1. Pre-development pollutant load based on the existing impervious cover:

Lpre(existing) = [0.05 + (0.009 x Iexisting)] x A x 2.28 (Equation 5-17)

Lpre(existing) =

County Number: 74

PERFORMANCE-BASED WATER QUALITY CALCULATIONS

WORKSHEET 3 : SITUATION 3

Prince George relative pre-development total phosphorous load (pounds per year)

Version 8.14.15

Performance Based Water Quality

104697 Fort Lee Entrance

Project No. 104697

Calc. By: RJW

County:

16.00 %

12.79 acres

5.66

43.63 %

12.79 acres

12.91

RR=

RR= 2.66

or

RR=

RR= 7.25

Page 2 or 5

WORKSHEET 3 : SITUATION 3

Lpre(watershed) = relative pre-development total phosphorous load (pounds per year)

Lpre(watershed) = [0.05 + (0.009 x Iwatershed)] x A x 2.28 (Equation 5-16)

2. Pre-development pollutant load based on the average land cover condition:

pounds per year

Lpost - Lpre(watershed) pounds per year

Lpost = pounds per year

STEP 6 Determine the relative pollutant removal requirement (RR) .

Lpost - (0.9 x Lpre(existing))

A = applicable area (acres)

Ipost =

A =

Ipost = post-development percent impervious cover (percent expressed in whole numbers)

Lpre(watershed) = pounds per year

STEP 5 Determine the relative post-development pollutant load (Lpost).

Lpost = [0.05 + (0.009 x Ipost)] x A x 2.28 (Equation 5-21)

Iwatershed =

A =

Iwatershed = average land cover condition for specific watershed or locality or 16%, expressed in whole numbers

Lpost = relative post-development total phosphorous load (pounds per year)

Prince GeorgeCounty Number: 74

PERFORMANCE-BASED WATER QUALITY CALCULATIONS

A = applicable area (acres)

Version 8.14.15

Performance Based Water Quality

104697 Fort Lee Entrance

Project No. 104697

Calc. By: RJW

County:

RR= 2.66

EFF= 20.60 %

Sta: / offset

Sta: / offset

Sta: / offset

Sta: / offset

Sta: / offset

Sta: / offset

Sta: / offset

RR = pollutant removal requirement (pounds per year)

2. Select BMP(s) from Table 5-14 and locate on the site:

Sta: / offset

Sta: / offset

EFF = ( RR ÷ Lpost ) x 100 (Equation 5-22)

Lpost = relative post-development total phosphorous load (pounds per year)

EFF = required pollutant removal efficiency (percent in whole numbers)

The pollutant removal required (RR) for situation 3 is the lesser of the two values calculated pounds per year

STEP 7 Identify best management practice (BMP) for site.

1. Determine the required pollutant removal efficiency for site:

Performance Based Water Quality

104697 Fort Lee Entrance

Project No. 104697

Calc. By: RJW

09/08/16

VAB

County Number: 74

PERFORMANCE-BASED WATER QUALITY CALCULATIONS

WORKSHEET 3 : SITUATION 3

Prince George Version 8.14.15 abiot.gemechu Text Box Extended detention (2 X WQ Vol.)

County:

RR= 2.66

EFF= 20.60 %

Sta: / offset

Sta: / offset

Sta: / offset

Sta: / offset

Sta: / offset

Sta: / offset

Sta: / offset

RR = pollutant removal requirement (pounds per year)

2. Select BMP(s) from Table 5-14 and locate on the site:

Extended detention (2 X WQ Vol.)

Sta: / offset

Sta: / offset

EFF = ( RR ÷ Lpost ) x 100 (Equation 5-22)

Lpost = relative post-development total phosphorous load (pounds per year)

EFF = required pollutant removal efficiency (percent in whole numbers)

The pollutant removal required (RR) for situation 3 is the lesser of the two values calculated pounds per year

STEP 7 Identify best management practice (BMP) for site.

1. Determine the required pollutant removal efficiency for site:

Performance Based Water Quality 104697 Fort Lee Entrance

Project No. 104697 Calc. By: RJW

09/08/16

VAB

County Number: 74

PERFORMANCE-BASED WATER QUALITY CALCULATIONS

WORKSHEET 3 : SITUATION 3

Prince George Version 8.14.15

County:

Sta: / offset

Sta: / offset

Sta: / offset

Sta: / offset

Sta: / offset

County Number: 74 Prince George

PERFORMANCE-BASED WATER QUALITY CALCULATIONS

WORKSHEET 3 : SITUATION 3

Sta: / offset

Performance Based Water Quality

104697 Fort Lee Entrance

Project No. 104697

Version 8.14.15

09/08/16

Calc. By: RJW VAB

Sta: / offset

Sta: / offset

Sta: / offset

Sta: / offset

Sta: / offset

Sta: / offset

Sta: / offset

Sta: / offset

Sta: / offset

Sta: / offset

Sta: / offset

Sta: / offset

Sta: / offset

County:

Sta: / offset

Sta: / offset

Sta: / offset

Sta: / offset

Sta: / offset

Sta: / offset

Sta: / offset

Sta: / offset

Sta: / offset

Sta: / offset

Sta: / offset

Sta: / offset

Sta: / offset

Sta: / offset

Sta: / offset

Sta: / offset

Sta: / offset

Sta: / offset

Sta: / offset

County Number: 74 Prince George

PERFORMANCE-BASED WATER QUALITY CALCULATIONS

WORKSHEET 3 : SITUATION 3

Version 8.14.15

Performance Based Water Quality

104697 Fort Lee Entrance

Project No. 104697 09/08/16

Calc. By: RJW VAB

County:

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

Lremoved

(Lbs/YR) Comments

LBMP = [0.05 + (0.009 x Ibmp)] x A x 2.28 (Equation 5-23)

Lremoved = EFFBMP x LBMP (Equation 5-24)

LBMP = relative post-development total phosphorous load entering proposed BMP (pounds per year)

IBMP =

BMP Str.#

BMP "A"

(acres)

BMP Imp.

Area (ac.)

IBMP (%) LBMP EFFBMP

Carryover

LBMP

Total

LBMP

EFFBMP = pollutant removal efficiency of BMP (expressed in decimal form)

Prince George

Post-development pollutant removed by proposed BMP (pounds per year) drainage area of proposed BMP (acres)

Lremoved =

Performance Based Water Quality

104697 Fort Lee Entrance

Project No. 104697

Calc. By: RJW VAB

09/08/16

3. and 4. Determine the pollutant load entering the proposed BMP (s) and Calculate the pollutant load removed by the proposed BMP(s):

Post-development percent impervious cover of BMP drainage area (percent expressed in whole numbers

A =

Version 8.14.15County Number: 74

PERFORMANCE-BASED WATER QUALITY CALCULATIONS

County:

1.00 5.25 1.75 33.33 4.19 4.19 0.35 1.47

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

Lremoved (Lbs/YR)

Comments

LBMP = [0.05 + (0.009 x Ibmp)] x A x 2.28 (Equation 5-23)

Lremoved = EFFBMP x LBMP (Equation 5-24)

LBMP = relative post-development total phosphorous load entering proposed BMP (pounds per year)

IBMP =

BMP Str.# BMP "A" (acres)

BMP Imp.

Area (ac.) IBMP (%) LBMP EFFBMP

Carryover

LBMP

Total

LBMP

EFFBMP = pollutant removal efficiency of BMP (expressed in decimal form)

Prince George

Post-development pollutant removed by proposed BMP (pounds per year) drainage area of proposed BMP (acres)

Lremoved =

Performance Based Water Quality 104697 Fort Lee Entrance

Project No. 104697 Calc. By: RJW VAB

09/08/16

3. and 4. Determine the pollutant load entering the proposed BMP (s) and Calculate the pollutant load removed by the proposed BMP(s):

Post-development percent impervious cover of BMP drainage area (percent expressed in whole numbers

A =

Version 8.14.15County Number: 74

PERFORMANCE-BASED WATER QUALITY CALCULATIONS

County:

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

0.00 0.00

Carryover

LBMP

Total

LBMP

3. and 4. Determine the pollutant load entering the proposed BMP (s) and Calculate the pollutant load removed by the proposed BMP(s):

BMP Str.#

BMP "A"

(acres)

BMP Imp.

Area (ac.)

IBMP (%) LBMP EFFBMP

Lremoved

(Lbs/YR) Comments

County Number: 74 Prince George

PERFORMANCE-BASED WATER QUALITY CALCULATIONS

WORKSHEET 3 : SITUATION 3

Version 8.14.15

Performance Based Water Quality

104697 Fort Lee Entrance

Project No. 104697 09/08/16

Calc. By: RJW VAB

County:

where:

1.47

RR= 2.66

1.19

2.66 ≥ 2.66

Pounds/year

WORKSHEET 3 : SITUATION 3

5. Calculate the total pollutant load removed by the BMP (s):

Lremoved/total = Lremoved/BMP1 + Lremoved/BMP2 + Etc…. (equation 5-25)

Lremoved/total =

Lremoved/BMP1=

Lremoved/BMP2 =

County Number: 74

PERFORMANCE-BASED WATER QUALITY CALCULATIONS

Version 8.14.15

Total pollutant load removed by proposed BMP's pollutant load removed by BMP1 pollutant load removed by BMP2

Prince George

Performance Based Water Quality

104697 Fort Lee Entrance

Project No. 104697

Calc. By: RJW

09/08/16

VAB

See chart on sheet 4 of 5 for individual BMP removal

Lremoved/total =

6. Verify compliance:

Lremoved/total ≥ RR

Nutrient Credits Purchased

Total phosphorous Removal OK

Pounds/year

APPENDIX C:

Inlet Calculations

VDOT ROADWAY SPREAD ANALYSIS REPORT

Road: Route 36 Units: U.S. Customary X Sheet: of Project #: 104697 Fort Lee Entrance (Outfall 4-06 and Ex 9-04) Metric (SI) Prepared by: Abiot Gemechu Date: 3/8/18

Checked by: Date:

9-02 23+57.66 45.71 DI-3B 8 0.2500 0.90 4.00 0.91 0.00 0.91 0.029 0.0280 2.0000 0.0833 0.013 2.80 8.00 0.18 0.91 0.00 4-07 28+15.15 59.50 DI-3A 0.0490 0.77 4.00 0.15 0.74 0.89 0.019 N/A 2.0000 0.0833 0.013 7.90 8.00 0.28 0.89 0.00 4-03 28+58.53 59.50 DI-3A 0.5870 0.57 4.00 1.34 0.00 1.34 0.019 0.0190 2.0000 0.0833 0.013 4.70 8.00 0.22 0.61 0.74 4-02 28+08.75 59.50 DI-3A 0.0570 0.72 4.00 0.16 0.00 0.16 0.018 N/A 2.0000 0.0833 0.013 2.60 8.00 0.18 0.16 0.00 4-01 27+58.69 59.50 DI-3A 0.2020 0.59 4.00 0.48 0.00 0.48 0.019 0.0000 2.0000 0.0833 0.013 5.30 8.00 0.23 0.48 0.00 4-05 28+10.02 2.69 DI-7 Grate 0.1430 0.76 4.00 0.44 0.00 0.44 0.019 N/A n/a 0.0833 0.013 3.60 12.00 0.06 0.44 0.00 4-04 28+14.47 69.40 DI-7 Grate 0.0740 0.35 4.00 0.10 0.00 0.10 0.019 N/A n/a 0.0833 0.013 3.50 12.00 0.02 0.10 0.00 4-10 27+05 2.69 DI-7 Grate 0.4410 0.76 4.00 1.35 0.00 1.35 0.019 N/A n/a 0.0833 0.013 3.90 12.00 0.12 1.35 0.00 4-09 29+15 2.69 DI-7 Grate 0.1400 0.76 4.00 0.43 0.00 0.43 0.019 N/A n/a 0.0833 0.013 3.60 12.00 0.06 0.43 0.00

Manning's "n"

Structure No. Station Offset VDOT

Standard

Drainage Area

(acres)

Previous Inlet Bypass

(cfs)

Total Discharge

(cfs)

Cross Slope (ft/ft)

Logitudinal Slope

Flow (Total Bypassed)

(cfs)

Allowable Spread

(ft)

Ponded Depth

(ft)

Intercepted Rational Flow

(cfs)

Composite Runoff

Coefficient

Calculated Spread

(ft)

Gutter/Local Depress. Width

(ft)

Gutter Slope (ft/ft)

Rainfall Intensity

(in/hr)

Inlet Discharge

(cfs)

Project #: 104697 Fort Lee Entrance Metric (SI) Prepared by:

Checked by:

5-04 10+99.40 16.15 ES-1 or 2 (24") n/a n/a n/a 0.52 0.00 0.52 0.083 0.0000 n/a 0.0304 0.015 3.92 8.00 N/A N/A 0.12

5-03 10+98.59 6.00 DI-3B 8 0.15 0.90 4.00 0.52 0.00 0.52 0.083 1.5600 2.0000 0.0304 0.015 3.92 8.00 6.43 N/A 0.12

5-02 505+89.36 12.28 DI-3B 12 0.16 0.87 4.00 0.55 0.00 0.55 0.008 3.1600 2.0000 0.0084 0.015 7.80 8.00 11.81 N/A 0.07

8-09 16+71.41 161.64 SWM-1 n/a n/a n/a 0.52 0.00 0.52 0.083 1.5600 n/a 0.0304 0.015 3.92 8.00 N/A N/A 0.12

Remarks:

HEC-12 is used for spread and bypass computations

All other computations done using GEOPAK Drainage

Allowable

Spread

(ft)

ComputedSlot

Length (100% Eff.)

(ft)

Sumped

Spread

(ft)

Ponded

Depth

(ft)

Previous

Inlet Bypass

(cfs)

Total

Discharge

(cfs)

Cross

Slope

(ft/ft)

Logitudinal

Slope

Manning's

"n"

Calculated

Spread

(ft)

Gutter/Local

Depress. Width

(ft)

Gutter

Slope

(ft/ft)

Rainfall

Intensity

(in/hr)

Inlet

Discharge

(cfs)

Structure

No.

Station Offset

VDOT

Standard

Drainage

Area

(acres)

Composite

Runoff

Coefficient

Project #: 104697 Fort Lee Entrance (Outfall 8-02) Metric (SI) Prepared by:

Checked by:

8-02 27+38.65 -126.97 ES-2 15" n/a n/a n/a 0.86 0.00 0.86 0.016 0.0000 n/a 0.0833 0.015 1.87 8.00 N/A N/A 0.16

8-01 26+75.19 2.00 DI-3C 6 0.14 0.50 4.00 0.41 0.12 0.53 0.016 1.1600 2.0000 0.0833 0.014 5.19 8.00 3.44 0.84 0.07

5-01 26+24.97 2.00 DI-3B 4 0.42 0.50 4.00 0.84 0.00 0.84 0.020 1.1600 2.0000 0.0833 0.014 3.95 8.00 5.83 N/A 0.21

8-10 27+25.26 2.00 DI-2B 4 0.29 0.50 4.00 0.58 0.00 0.58 0.083 0.9600 2.0000 0.0833 0.013 2.25 8.00 4.70 N/A 0.19

Remarks:

HEC-12 is used for spread and bypass computations

All other computations done using GEOPAK Drainage

Rainfall

Intensity

(in/hr)

Inlet

Discharge

(cfs)

Structure

No.

Station Offset

VDOT

Standard

Drainage

Area

(acres)

Composite

Runoff

Coefficient

Previous

Inlet Bypass

(cfs)

Total

Discharge

(cfs)

Cross

Slope

(ft/ft)

Logitudinal

Slope

Manning's

"n"

Calculated

Spread

(ft)

Gutter/Local

Depress. Width

(ft)

Gutter

Slope

(ft/ft)

Allowable

Spread

(ft)

ComputedSlot

Length (100% Eff.)

(ft)

Sumped

Spread

(ft)

Ponded

Depth

(ft)

Project #: 104697 Fort Lee Entrance Metric (SI) Prepared by:

Checked by:

8-08 17+31.59 115.46 ES-1 or 2 (18") n/a n/a n/a 1.77 0.00 1.77 0.029 0.0000 n/a 0.0833 0.014 4.43 8.00 N/A N/A 0.24

8-07 30+30.97 -146.08 DI-3C 6 0.33 0.90 4.00 1.19 0.00 1.19 0.020 1.1600 2.0000 0.0200 0.015 10.31 8.00 3.44 7.14 0.14

8-06 17+86.92 40.14 DI-3B 6 0.21 0.76 4.00 0.64 0.00 0.64 0.015 0.6500 2.0000 0.0833 0.014 4.62 8.00 4.45 N/A 0.21

8-03 19+27.52 43.00 DI-3A 0.03 0.90 4.00 0.10 0.00 0.10 0.025 1.1200 2.0000 0.0833 0.013 1.12 8.00 2.31 N/A 0.09

8-04 31+44.17 2.00 DI-3C 6 0.33 0.90 4.00 1.20 0.00 1.20 0.020 1.1200 2.0000 0.0833 0.014 4.44 8.00 2.31 1.72 0.14

9-03 21+76.99 51.65 DI-3B 8 0.17 0.90 4.00 0.60 0.00 0.60 0.033 2.9600 2.0000 0.0833 0.013 1.85 8.00 6.69 N/A 0.15

8-05 31+51.83 15.67 DI-7 Grate 2.04 0.40 4.00 3.26 0.00 3.26 0.020 1.1200 n/a 0.0833 0.015 9.39 12.00 2.31 9.39 0.31

Remarks:

HEC-12 is used for spread and bypass computations

All other computations done using GEOPAK Drainage

Allowable

Spread

(ft)

ComputedSlot

Length (100% Eff.)

(ft)

Sumped

Spread

(ft)

Ponded

Depth

(ft)

Previous

Inlet Bypass

(cfs)

Total

Discharge

(cfs)

Cross

Slope

(ft/ft)

Logitudinal

Slope

Manning's

"n"

Calculated

Spread

(ft)

Gutter/Local

Depress. Width

(ft)

Gutter

Slope

(ft/ft)

Rainfall

Intensity

(in/hr)

Inlet

Discharge

(cfs)

Structure

No.

Station Offset

VDOT

Standard

Drainage

Area

(acres)

Composite

Runoff

Coefficient

APPENDIX D:

Storm Sewer

Calculations

LD-229 PROJECT104697 Fort Lee Entrance Designed by: Abiot Gemechu STORM SEWER DESIGN COMPUTATIONS UNITS Metric (SI)

Pre Development (Existing Flow), Pipe is CMP

Start Node Stop Node

System Drainage Area (Ac)

System Additional Flow (cfs)

System

CA

(acres)

Upstream Inlet Tc (hours)

System Intensity (in/h) Flow (cfs)

Invert (Start) (ft)

Invert (Stop) (ft)

Length (Scaled) (ft)

Slope (Calculate

d) (ft/ft)

Diameter (in)

Capacity (Design) (cfs)

Velocity (ft/s)

Time (Pipe Flow) (hours)

MANNIN

GS "n":

HW-EX EX4-04 44.90 0 8.978 0.43 3.77 34.12 102.95 102.15 56.9 0.014 18 12.43 19.31 0.001 0.013 EX4-04 EX4-05 45.86 0 9.443 0.1 3.766 35.85 101.41 100.87 62.3 0.009 24 11.41 11.41 0.002 0.024 EX4-05 HW-4-06 46.59 0 9.995 0.1 3.759 37.87 100.87 100.17 72.6 0.01 24 12.03 12.05 0.002 0.024 Note: Analysis done in StormCAD

Post Development (Proposed Condition Flow and Proposed Design)

Start Node Stop Node

System Drainage Area (Ac)

System Additional Flow (cfs)

System

CA

(acres)

Upstream Inlet Tc (hours)

System Intensity (in/h) Flow (cfs)

Invert (Start) (ft)

Invert (Stop) (ft)

Length (Scaled) (ft)

Slope (Calculate

d) (ft/ft)

Diameter (in)

Capacity (Design) (cfs)

Velocity (ft/s)

Time (Pipe Flow) (hours)

MANNIN

GS "n":

HW-Ex JB-4-04 44.90 0 8.978 0.43 3.77 34.12 102.94 101.58 45.00 0.031 18 18.42 19.31 0.00100 0.013 DI4-01 DI4-02 0.20 0 0.083 0.083 7.183 0.6 103.07 101.39 47.00 0.036 15 12.21 5.16 0.00300 0.013 DI4-03 MH-4-08 0.59 0 0.114 0.1 6.853 0.79 103.25 102.63 5.00 0.123 15 22.7 8.66 0.00000 0.013 MH-4-08 JB-4-04 0.59 0 0.114 0 6.85 0.79 102.63 101.58 42.00 0.024 15 10.03 4.86 0.00200 0.013 JB-4-04 DI4-02 45.56 0 4.559 0.083 3.767 17.31 101.58 101.39 5.00 0.038 24 44.1 13.19 0.00000 0.013 JB-4-04 DI4-07 0.00 0 4.559 0 3.767 17.31 101.58 101.39 5.00 0.038 24 44.1 0 0.00000 0.013 DI4-02 JB-4-05 45.82 0 4.683 0.083 3.767 17.78 101.39 100.87 55.00 0.009 24 22 7.79 0.00200 0.013 DI4-07 JB-4-05 0.05 0 4.597 0.083 3.767 17.45 101.39 100.87 55.00 0.009 24 22 7.77 0.00200 0.013 JB-4-05 Ex 4-06 46.59 0 3.391 0.083 3.757 12.84 100.87 100.17 *71 0.01 24 12.17 4.38 0.00500 0.024 DI9-02 DI-9-04 0.25 0 0.164 0.083 7.183 1.19 122.94 122.91 7.00 0.004 12 2.27 2.92 0.00100 0.013 DI-9-04 EX-1 0.25 0 0.164 0 7.175 1.19 122.91 122.6 74.00 0.004 12 2.28 2.94 0.00700 0.013 DI4-09 JB-4-05 0.14 0 0.106 0.083 7.183 0.77 101 100.87 100.00 0.001 24 8.03 1.61 0.01800 0.013 DI4-10 JB-4-05 0.44 0 0.335 0.083 7.183 2.43 101 100.87 100.00 0.001 24 7.75 2.18 0.01400 0.013 Note: Analysis done in StormCAD

LD-347 UNITS: US Customary X NETWORK NAMEOutfall 4-06 Sheet: 1 of 1 ROAD: Route 36 Metric (SI) Prepared by: Abiot Gemechu Date: 3/8/2018 Prince George PROJECT #: 104697 Fort Lee Entrance Checked by: Date: 10 STORM FREQENCY : 10 YEAR MANNINGS "n":

Start Node Stop Node Upstream Structure

Upstream Inlet C

Upstream Inlet Area (acres)

Upstream Inlet Tc (hours)

System Intensity

(in/h)

System

CA

(acres) Flow (cfs)

Elevation Crown

(Start) (ft)

Hydraulic Grade

Line (In) (ft)

Elevation Crown

(Stop) (ft)

Hydraulic Grade Line

(Out) (ft) Length (ft) Diameter

(in) Span (ft) Rise (ft) Number of

Barrels

Friction Slope

(ft/ft) Slope (Calculated)

(ft/ft) Velocity

(ft/s)

Capacity (Full Flow)

(cfs)

Time (Pipe Flow)

(hours)

MANNINGS

"n":

HW-Ex JB-4-04 HW-Ex 0.200 44.889 0.43 3.77 8.98 34.12 104.45 107.75 103.09 103.080 45.00 18.00 1.00 0.11 0.031 19.31 18.42 0.0010 0.013 DI4-01 DI4-02 DI4-01 0.590 0.202 0.083 7.18 0.08 0.60 104.33 103.37 102.65 102.910 47.00 15.00 1.00 0.01 0.036 5.16 12.21 0.0030 0.013 DI4-03 MH-4-08 DI4-03 0.570 0.587 0.1 6.85 0.11 0.79 104.51 103.60 103.89 103.010 5.00 15.00 1.00 0.12 0.123 8.66 22.7 0.0000 0.013

MH-4-08 JB-4-04 MH-4-08 (N/A) (N/A) (N/A) 6.85 0.11 0.79 103.89 103.01 102.84 103.080 42.00 15.00 1.00 0.00 0.024 4.86 10.03 0.0020 0.013 JB-4-04 DI4-02 JB-4-04 0.350 0.074 0.083 3.77 4.56 17.31 103.59 103.08 103.40 102.910 5.00 24.00 1.00 0.04 0.038 13.19 44.1 0.0000 0.013 JB-4-04 DI4-07 JB-4-04 0.350 0.074 0.083 3.77 4.56 17.31 103.59 103.08 103.40 102.900 5.00 24.00 1.00 0.04 0.038 0 44.1 0.0000 0.013 DI4-02 JB-4-05 DI4-02 0.720 0.057 0.083 3.77 4.68 17.78 103.40 102.91 102.88 102.550 55.00 24.00 1.00 0.01 0.009 7.79 22 0.0020 0.013 DI4-07 JB-4-05 DI4-07 0.770 0.049 0.083 3.77 4.60 17.45 103.40 102.90 102.88 102.550 55.00 24.00 1.00 0.01 0.009 7.77 22 0.0020 0.013

JB-4-05 Ex 4-06 JB-4-05 0.760 0.143 0.083 3.76 3.39 12.84 102.88 102.55 102.18 101.460 *71 24.00 1.00 0.01 0.01 4.38 12.17 0.0050 0.024 DI9-02 DI-9-04 DI9-02 0.900 0.25 0.083 7.18 0.16 1.19 123.95 123.45 123.92 123.420 7.00 12.00 1.00 0.00 0.004 2.92 2.27 0.0010 0.013 DI-9-04 EX-1 DI-9-04 (N/A) (N/A) (N/A) 7.18 0.16 1.19 123.92 123.42 123.61 123.060 74.00 12.00 1.00 0.00 0.004 2.94 2.28 0.0070 0.013 DI4-09 JB-4-05 DI4-09 0.760 0.14 0.083 7.18 0.11 0.77 103.01 102.55 102.88 102.550 100.00 24.00 1.00 0.00 0.001 1.61 8.03 0.0180 0.013 DI4-10 JB-4-05 DI4-10 0.760 0.441 0.083 7.18 0.34 2.43 103.01 102.56 102.88 102.550 100.00 24.00 1.00 0.00 0.001 2.18 7.75 0.01 0.013

Remarks: Computations done using SUDA

Existing 18" Conc. Pipe from Park Property cannot be replaced

Flow is routed through pipe storage

NOTES

COUNTY or

FREQUENCY

NOTES / REMARKS

LD-229 PROJECT: Designed by:

STORM SEWER DESIGN COMPUTATIONS LOCATION:

COUNTY: Checked by:

STORM FREQUENCY 10

UNITS ENGLISH

DRAIN. RUNOFF CA INLET RAIN RUNOFF INVERT ELEVATIONS LENGTH ENGLISH SIZE CAPACITY VELOCITY FLOW

FROM POINT TO POINT AREA COEFF. INCRE- ACCUM- TIME FALL Q UPPER LOWER of Pipe (Dia. Or TIME

REFERENCE REFERENCE "A" "C" MENT ULATED END END Span/Rise)

Acre Minutes In/Hr CFS Ft. Ft./Ft. In. CFS Ft/Sec Minutes

8-09 5-02 0.000 0.000 0.000 0.000 0.00 0.00 11.42 111.25 110.58 150.06 0.0045 24.00 15.12 5.33 0.470

5-02 5-03 0.157 0.870 0.136 0.136 0.00 87.73 11.97 110.48 109.97 102.51 0.0050 24.00 15.96 5.58 0.306

5-03 5-04 0.145 0.900 0.131 0.267 0.00 46.78 12.49 109.87 109.75 6.85 0.0175 24.00 29.93 9.08 0.013

ROAD: Route 36 UNITS: US Customary X NETWORK NAME: Sheet: of

PROJECT #: 104697 Fort Lee Entrance Metric (SI) Prepared by: Date:

Checked by: Date:

PIPE SIZE

(in or mm)

0.013

STATION

O F

F S

T

D

IS

T A

N C

(f t.

S

ID

E

LOWER

8-09 113.08 111.79 1.29 0.000%

113.25 112.58 0.67

111.25 110.58 0.67

5-02 111.78 111.21 0.57 0.282%

112.48 111.97 0.51

110.48 109.97 0.51

5-03 111.16 110.83 0.34 0.307%

111.87 111.75 0.12

109.87 109.75 0.12

Remarks: Computations done using Geopak Drainage

10+98.59 6.00 Rt. 5-04 1.75%

6.85 24 1 9.08 29.93 0.010.00 46.78 0.267 12.49 113.17 2.01

ACCEL

DI-3B 8 Curb 0.900 0.145 0.267

505+89.36 12.28 Rt. 5-03 0.50%

102.51 24 1 5.58 15.96 0.310.00 87.73 0.136 11.97 114.09 2.31

LEESB

DI-3B 12 Curb 0.870 0.157 0.136

VDOT STORM SEWER TABULATION REPORT

RISE

SPAN

H G

L C

L E

A R

A N

C E ft o r m

ALIGNMENT NAME

P

IP

E C

A P

A C

IT

Y c fs o r c m s

)LOCATION

OF

UPPER END COUNTY or CITY:

S U

B -T

O T

A L

(C *A

0.00

T O

T A

L A

C C

U M

A L

A T

E D

C

*A

F L

O W

V E

L O

C

IT

Y fp s o r m p s

0.47

NOTES

AND

REMARKS

A R

E A

LEE

161.64 Rt.

SWM-1

5-0216+71.41

DRAINAGE

AREA (ac. or ha.)

0.000 0.000 0.000

C O

M P

O S

IT

E

C V

A L

U E

FREQUENCY (yrs):

MANNINGS "n":

F R

IC

T

IO

N

S L

O P

E

P

IP

O P

E

5.33

T

IM

E O

F F

L O

W I N

S E

C T

IO

N m in

Total runoff (routed from basin) = 11.42 cfs

N U

M B

E R

O F

B A

R R

E L

S

13.42111.25

IN

L

E T

T H

R O

A T

O R

M A

N H

O

O

P E

L E

V A

T

IO

N ft o r m

NOTES / REMARKS

15.12 0.45%

11.42

C U

M U

L A

T

IV

E T

IM

E

F

N C

E N

T R

A T

IO

N m in

F A t o r m

150.06

U P

P E

R E o r m

HYDRAULIC GRADE LINE

ELEVATION

CROWN ELEVATION

T O

T A

L R

U N

O F

F Q c fs O

R c m s

IN

T

E N

S

IT

Y in /h r O

R m m /h r)

0.000

V D

O T

S T

A N

D A

R D

U

P P

E R

S T

R U

C T

U R

E

N O

UPPER

T Y

P E

O F

S T

R U

C T

U R

E

U P

P E

R

P

IP

E L

E N

G T

H ft o r m

L O

W E

R E o r m

FLOWLINE ELEVATION

Other 0.00

COUNTY: Checked by:

STORM FREQUENCY 10

UNITS ENGLISH

DRAIN. RUNOFF CA INLET RAIN RUNOFF INVERT ELEVATIONS LENGTH ENGLISH SIZE CAPACITY VELOCITY FLOW

FROM POINT TO POINT AREA COEFF. INCRE- ACCUM- TIME FALL Q UPPER LOWER of Pipe (Dia. Or TIME

REFERENCE REFERENCE "A" "C" MENT ULATED END END Span/Rise)

Acre Minutes In/Hr CFS Ft. Ft./Ft. In. CFS Ft/Sec Minutes

8-10 8-01 0.289 0.500 0.145 0.145 0.00 4.00 0.58 112.13 111.94 47.63 0.0040 15.00 4.09 2.37 0.335

5-01 8-01 0.420 0.500 0.210 0.210 0.00 4.00 0.84 112.13 111.94 46.86 0.0040 15.00 4.09 2.62 0.298

8-01 8-02 0.143 0.500 0.071 0.426 0.00 4.00 1.71 111.94 111.38 144.33 0.0039 15.00 4.02 3.14 0.766

Checked by: Date:

PIPE SIZE

(in or mm)

Prince George

0.013

STATION

O F

F S

T A

N

S

ID

E

LOWER

8-10 114.52 114.51 0.00 0.008%

113.38 113.19 0.19

112.13 111.94 0.19

5-01 114.52 114.51 0.01 0.017%

113.38 113.19 0.19

112.13 111.94 0.19

8-01 114.51 114.41 0.10 0.071%

113.19 112.63 0.56

111.94 111.38 0.56

Remarks: Computations done using Geopak Drainage

V D

O T

S T

A N

D A

R D

U

P P

E R

S T

R U

C T

U R

E

N O

UPPER

T Y

P E

O F

S T

R U

C T

U R

E

U P

P E

R

P

IP

E L

E N

G T

H ft o r m

L O

W E

R E o r m

FLOWLINE ELEVATION

Curb 0.00 0.58

C U

M U

L A

T

IV

E T

IM

E

N C

E N

T R

A T

IO

N m in

F A o r m

47.63

U P

P E

R E o r m

HYDRAULIC GRADE LINE

ELEVATION

CROWN ELEVATION

T O

T A

L R

U N

O F

F Q c fs O

R c m s

IN

T

E N

S

IT

Y in /h r O

R m m /h r)

T

IM

E O

F F

L O

W I N

S E

C T

IO

N m in

N U

M B

E R

O F

B A

R R

E L

S

11.12115.64

DRAINAGE

AREA (ac. or ha.)

0.500 0.289 0.145

C O

M P

O S

IT

E

C V

A L

U E

FREQUENCY (yrs):

MANNINGS "n":

F R

IC

T

O P

E

P

O P

E

2.37

ENTRANCEREV

2.00 Rt.

DI-2B 4

8-0127+25.26

IN

L

E T

T H

R O

A T

O R

M A

N H

O

P E

L E

V A

T

IO

N ft o r m

NOTES / REMARKS

4.09 0.40%

0.1454.00

T O

T A

L A

C C

U M

A L

A T

E D

C

*A

F L

O W

V E

L O

C

IT

Y fp s o r m p s

0.33

NOTES

AND

REMARKS

A R

E A

VDOT STORM SEWER TABULATION REPORT

RISE

SPAN

H G

L C

L E

A R

A N

C E ft o r m

ALIGNMENT NAME

P

IP

E C

A P

A C

IT

Y c fs o r c m s

)LOCATION

OF

UPPER END COUNTY or CITY:

S U

B -T

O T

A L

(C *A

ENTRANCEREV

DI-3B 4 Curb 0.500 0.420 0.210 4.09 0.300.00 4.00 0.210 0.84 115.60 1.08 26+24.97 2.00 Rt. 8-01 0.40%

46.86 15 1 2.62

ENTRANCEREV

DI-3C 6 Curb 0.500 0.143 0.426 4.02 0.770.00 4.00 0.426 1.71 115.49 0.98 26+75.19 2.00 Rt. 8-02 0.39%

144.33 15 1 3.14

COUNTY: Checked by:

STORM FREQUENCY 10

UNITS ENGLISH

DRAIN. RUNOFF CA INLET RAIN RUNOFF INVERT ELEVATIONS LENGTH ENGLISH SIZE CAPACITY VELOCITY FLOW

FROM POINT TO POINT AREA COEFF. INCRE- ACCUM- TIME FALL Q UPPER LOWER of Pipe (Dia. Or TIME

REFERENCE REFERENCE "A" "C" MENT ULATED END END Span/Rise)

Acre Minutes In/Hr CFS Ft. Ft./Ft. In. CFS Ft/Sec Minutes

8-05 8-04 2.040 0.400 0.816 0.816 0.00 4.00 3.26 114.94 114.60 10.66 0.0319 15.00 11.54 8.09 0.022

9-03 8-03 0.167 0.900 0.150 0.150 0.00 4.00 0.60 116.23 113.72 247.18 0.0102 15.00 6.51 3.32 1.243

8-04 8-03 0.333 0.900 0.300 1.116 0.00 4.00 4.46 114.60 113.72 36.12 0.0244 18.00 16.40 7.89 0.076

8-03 8-06 0.027 0.900 0.024 1.290 0.00 4.00 5.16 113.62 112.34 138.19 0.0093 18.00 10.11 5.75 0.400

8-06 8-07 0.211 0.760 0.160 1.451 0.00 4.00 5.80 112.24 111.84 79.58 0.0050 18.00 7.45 4.69 0.283

8-07 8-08 0.331 0.900 0.298 1.749 0.00 4.00 6.99 111.74 111.61 21.71 0.0061 18.00 8.19 5.20 0.070

Checked by: Date:

PIPE SIZE

(in or mm)

0.013

STATION

O F

F S

T A

N

S

ID

E

LOWER

8-05 116.03 115.11 0.91 0.258%

116.19 115.85 0.34

114.94 114.60 0.34

9-03 116.65 113.98 2.67 0.009%

117.48 114.97 2.51

116.23 113.72 2.51

8-04 115.48 114.27 1.20 0.183%

116.10 115.22 0.88

114.60 113.72 0.88

8-03 114.52 113.10 1.42 0.244%

115.12 113.84 1.28

113.62 112.34 1.28

8-06 113.24 112.81 0.43 0.309%

113.74 113.34 0.40

112.24 111.84 0.40

8-07 112.81 112.63 0.18 0.448%

113.24 113.11 0.13

111.74 111.61 0.13

Remarks: Computations done using Geopak Drainage

30+30.97 -146.08 Lt. 8-08 0.61%

21.71 18 1 5.20 8.19 0.070.00 4.00 1.749 6.99 117.03 4.22

ENTRANCEREV

DI-3C 6 Curb 0.900 0.331 1.749

17+86.92 40.14 Rt. 8-07 0.50%

79.58 18 1 4.69 7.45 0.280.00 4.00 1.451 5.80 116.54 3.30

LEE

DI-3B 6 Curb 0.760 0.211 1.451

19+27.52 43.00 Rt. 8-06 0.93%

138.19 18 1 5.75 10.11 0.400.00 4.00 1.290 5.16 117.62 3.10

LEE

DI-3A Curb 0.900 0.027 1.290

31+44.17 2.00 Rt. 8-03 2.44%

36.12 18 1 7.89 16.40 0.080.00 4.00 1.116 4.46 117.64 2.16

ENTRANCEREV

DI-3C 6 Curb 0.900 0.333 1.116

21+76.99 51.65 Rt. 8-03 1.02%

247.18 15 1 3.32 6.51 1.240.00 4.00 0.150 0.60 122.13 5.48

LEE

DI-3B 8 Curb 0.900 0.167 0.150

VDOT STORM SEWER TABULATION REPORT

RISE

SPAN

H G

L C

L E

A R

A N

C E ft o r m

ALIGNMENT NAME

P

IP

E C

A P

A C

IT

Y c fs o r c m s

)LOCATION

OF

UPPER END COUNTY or CITY:

S U

B -T

O T

A L

(C *A

4.00

T O

T A

L A

C C

U M

A L

A T

E D

C

*A

F L

O W

V E

L O

C

IT

Y fp s o r m p s

0.02

NOTES

AND

REMARKS

A R

E A

ENTRANCEREV

15.67 Rt.

DI-7 Grate

8-0431+51.83

DRAINAGE

AREA (ac. or ha.)

0.400 2.040 0.816

C O

M P

O S

IT

E

C V

A L

U E

FREQUENCY (yrs):

MANNINGS "n":

F R

IC

T

O P

E

P

O P

E

8.09

T

IM

E O

F F

L O

W I N

S E

C T

IO

N m in

N U

M B

E R

O F

B A

R R

E L

S

11.18117.21

IN

L

E T

T H

R O

A T

O R

M A

N H

O

P E

L E

V A

T

IO

N ft o r m

NOTES / REMARKS

11.54 3.19%

3.26

C U

M U

L A

T

IV

E T

IM

E

N C

E N

T R

A T

IO

N m in

F A o r m

10.66

U P

P E

R E o r m

HYDRAULIC GRADE LINE

ELEVATION

CROWN ELEVATION

T O

T A

L R

U N

O F

F Q c fs O

R c m s

IN

T

E N

S

IT

Y in /h r O

R m m /h r)

0.816

V D

O T

S T

A N

D A

R D

U

P P

E R

S T

R U

C T

U R

E

N O

UPPER

T Y

P E

O F

S T

R U

C T

U R

E

U P

P E

R

P

IP

E L

E N

G T

H ft o r m

L O

W E

R E o r m

FLOWLINE ELEVATION

Grate 0.00

APPENDIX E:

Ditch

D= D= D= 104697

RJW

Entrance LANE 1 b

1 1 b

1 1 b

1 Prince George

LT SIDE 3 --- 2 6 --- 6 9 --- 9 5/18/2016

1 2 3 1 of 2

Earth n= 0.03

Tc I2 Q2 Slope VEL. VEL DEP VEL DEP I10 Q10 DEP

A (ac) CA A (ac) CA A (ac) CA INCR. ACC. (min) (cfs) (Ft/Ft) (ft/sec) (ft/sec) (ft) (ft/sec) (ft) (cfs) (ft) REMARKS

25+00 25+25 25 0.008 0.007 0.015 0.008 0 0.014 0.014 5.0 5.71 0.082 3 0.051 2.0 1.32 0.90 0.10 0.00 7.21 0.10 0.11

25+25 25+50 25 0.008 0.007 0.015 0.008 0 0.014 0.029 5.5 5.57 0.161 3 0.042 2.0 1.47 1.00 0.13 0.00 7.05 0.20 0.15

25+50 25+75 25 0.008 0.007 0.015 0.008 0 0.014 0.043 5.9 5.46 0.236 2 0.008 2.0 0.94 0.64 0.25 0.00 6.92 0.30 0.27

25+75 26+00 25 0.008 0.007 0.015 0.008 0 0.014 0.058 6.5 5.30 0.305 1 0.007 2.0 1.18 0.81 0.39 0.00 6.71 0.39 0.43

26+00 26+25 25 0.008 0.007 0.015 0.008 0 0.014 0.072 7.0 5.17 0.372 1 0.004 2.0 0.96 0.65 0.48 0.00 6.56 0.47 0.52

26+25 26+50 25 0.008 0.007 0.015 0.008 0 0.014 0.086 7.7 5.03 0.434 1 0.008 2.0 1.32 0.90 0.44 0.00 6.38 0.55 0.48

26+50 26+75 25 0.008 0.007 0.015 0.008 0 0.014 0.101 8.2 4.93 0.497 1 0.006 2.0 1.25 0.85 0.48 0.00 6.26 0.63 0.53

26+75 27+00 25 0.008 0.007 0.015 0.008 0 0.014 0.115 8.6 4.83 0.556 1 0.005 2.0 1.21 0.83 0.52 0.00 6.14 0.71 0.57

27+00 27+25 25 0.008 0.007 0.015 0.008 0 0.014 0.13 9.1 4.73 0.613 1 0.005 2.0 1.24 0.85 0.54 0.00 6.02 0.78 0.59

DI(XX)

29+00 28+75 25 0.012 0.011 0.009 0.005 0 0.015 0.015 5.0 5.71 0.087 1 0.022 2.0 1.31 0.89 0.20 0.00 7.21 0.11 0.21

28+75 28+50 25 0.012 0.011 0.009 0.005 0 0.015 0.031 5.5 5.57 0.171 1 0.022 2.0 1.55 1.06 0.25 0.00 7.05 0.22 0.28

28+50 28+25 25 0.012 0.011 0.009 0.005 0 0.015 0.046 5.9 5.47 0.251 1 0.022 2.0 1.72 1.17 0.29 0.00 6.92 0.32 0.32

28+25 28+00 25 0.012 0.011 0.009 0.005 0 0.015 0.061 6.2 5.38 0.329 1 0.022 2.0 1.83 1.25 0.32 0.00 6.81 0.42 0.35

28+00 27+75 25 0.012 0.011 0.009 0.005 0 0.015 0.077 6.5 5.29 0.405 1 0.018 2.0 1.80 1.23 0.36 0.00 6.71 0.51 0.40

27+75 27+50 25 0.012 0.011 0.009 0.005 0 0.015 0.092 6.9 5.21 0.478 1 0.008 2.0 1.40 0.95 0.45 0.00 6.61 0.61 0.49

27+50 27+25 25 0.012 0.011 0.009 0.005 0 0.015 0.107 7.3 5.11 0.547 1 0.008 2.0 1.45 0.99 0.47 0.00 6.48 0.69 0.51 n=0.015

STA. TO STA. A

L

L

W

V

L n=0.05

Protective Lining

F L

N G

T H ft

0.9 0.5 0.3 CA

T Y

P

S E

C T

IO

N

Typ. Section Typ. Section Typ. Section SHEET

LD-268

PROJECT

BY

LOCATION

DATE

RJW

RTE 36 LANE 1

b

1 1 b

1 1 b

1 Prince George

RT SIDE 2.76 --- 4.45 3.33 --- 4.25 4.38 --- 3.1 5/18/2016

1 2 3 2 of 2

Earth n= 0.03

Tc I2 Q2 Slope VEL. VEL DEP VEL DEP I10 Q10 DEP

A (ac) CA A (ac) CA A (ac) CA INCR. ACC. (min) (cfs) (Ft/Ft) (ft/sec) (ft/sec) (ft) (ft/sec) (ft) (cfs) (ft) REMARKS

10+00 10+50 50 0.079 0.071 0.146 0.073 0 0.144 0.144 5.0 5.71 0.82 1 0.020 2.0 2.05 1.40 0.40 0.00 7.21 1.04 0.44

10+50 11+00 50 0.026 0.023 0.027 0.014 0 0.037 0.181 5.6 5.54 1.001 2 0.014 2.0 1.89 0.00 3.17 0.29 7.01 1.27 0.32 Paved Ditch

11+00 11+50 50 0.019 0.017 0.02 0.01 0 0.027 0.208 5.9 5.47 1.136 3 0.068 2.0 3.52 0.00 5.92 0.23 6.92 1.44 0.25 Paved Ditch

Outfall

Typ. Section Typ. Section Typ. Section SHEET

LD-268

PROJECT

BY

LOCATION

DATE

Protective Lining

F L

N G

T H ft

0.9 0.5 0.3 CA

T Y

P

S E

C T

IO

N

STA. TO STA. A

L

L

V

L n=0.05 n=0.015

AG

1 b 1 1 b 1 1 b 1 Prince George

Str 3-01, PG-5, Outfall to Shou 2 2 2 6 --- 6 9 --- 9 3/14/2018 1 2 3 1 of 2

Earth n= 0.03

Tc I2 Q2 Slope VEL. VEL DEP VEL DEP I10 Q10 DEP A (ac) CA A (ac) CA A (ac) CA INCR. ACC. (min) (cfs) (Ft/Ft) (ft/sec) (ft/sec) (ft) (ft/sec) (ft) (cfs) (ft) REMARKS

10+00 10+06 6 0.079 0.071 0 0 0.071 0.071 5.0 5.71 0.406 1 0.112 2.0 2.68 1.94 0.10 4.15 0.05 7.21 0.51 0.11 Str 3-01 to Ex Ditch n=0.015

STA. TO STA. AL

LO

VE

L.

n=0.05 Protective Lining

FL

LE

G

TH

(f t)

0.9 0.5 0.3 CA

TY

P.

SE

TI

O N

Typ. Section Typ. Section Typ. Section SHEET

LD-268 PROJECT

BY

LOCATION

DATE

AG

RTE 36 LANE 1 b 1 1 b 1 1 b 1 Prince George

RT SIDE, 3 3 6 --- 6 9 --- 9 3/14/2018

1 2 3 1 of 2

Earth n= 0.03

Tc I2 Q2 Slope VEL. VEL DEP VEL DEP I10 Q10 DEP A (ac) CA A (ac) CA A (ac) CA INCR. ACC. (min) (cfs) (Ft/Ft) (ft/sec) (ft/sec) (ft) (ft/sec) (ft) (cfs) (ft) REMARKS

35+75 38+50 275 0.2 0.18 0 0.163 0.049 0.229 0.229 5.0 5.71 1.305 1 0.014 2.0 2.09 1.42 0.55 3.51 0.35 7.21 1.65 0.38 Outfall to Str 5-06

Typ. Section Typ. Section Typ. Section SHEET

LD-268 PROJECT

BY

LOCATION

DATE

Protective Lining

FL

LE

G

TH

(f t)

0.9 0.5 0.3 CA

TY

P.

SE

TI

O N

STA. TO STA. AL

LO

VE

L.

n=0.05 n=0.015

APPENDIX F:

Inlets Drainage Area

BAS

IN

DETENTI

ON

5-064-01

4-03

4-04

4-02

4-05

4-06

5-01

5-06

5-02

5-03

5-04

8-01

8-05

8-04

8-03

8-06

8-07

8-08

8-09

-0

-0

3-01

8-10

8-11 w =1 0' w =1 0'

112 113 114 115 116

Top of Be rm Ele v.=11 6.50

T op of B erm

E lev.=116

.5

-0

7 8 -0

-0

-0

8-02

8-12

4-07

-0

-0

4-08

-0

-0

1 4 -0

E x ist.P a r k

-0

-0

-0

-10

In Pl. 12" Conc. Pipe

Ex-5-07 Ex-5-08

E x t 5

-0

E x t

-0

E X -1

E x i s

A

(E x

3-01

CF

F C C

F

F C

Paved Shoulder

Paved Shoulder

8' Paved Shoulder

APPENDIX G:

BASIN ROUTING

CALCULATIONS

User Name: rebecca.worley Date: 11-28-16

Project: 104697Basin Time: 15:13:08

Scenario: 104697 Basin 8-09 Page: 1

FLOOD HYDROGRAPH REPORT

Hydrograph Number: 4

Name: Routed 2 Year Storm

Type: Reservoir: Modified Puls

[HYDROGRAPH INFORMATION]

Peak Flow (Qp) = 0.15 (cfs)

Time to Peak (Tp) = 40.00 (min)

Time of Base (Tb) = 1800.00 (min)

Volume = 0.20 (ac-ft)

Time Step = 1.25 (min)

Peak Elevation = 114.01 (ft)

Detention Time = NA

[EQUATION]

(I1+I2) + (2(S1)/dt)-O1 = (2(S2)/dt)+O2

Where:

I1 = Previous inflow

I2 = Current inflow

S1 = Previous storage

S2 = Current storage dt = Time increment

O1 = Previous outflow abiot.gemechu Highlight

O2 = Current outflow

A = (I1 + I2)

B = (2 (S1) / dt) - O1

C = (2 (S2) / dt) + O2

FLOOD HYDROGRAPH REPORT

[Computation of Reservoir Outflow Table of Modified Puls Method]

[The time interval is 1.25 min]

Intv Time Inflow A B C Outflow Storage Elev

(min) (cfs) (cfs) (cfs) (cfs) (cfs) (cu ft) (ft)

1 1.25 0.55 0.55 0.00 32.87 0.00 20.54 111.31

2 2.50 1.10 1.64 32.87 131.46 0.00 82.16 111.40

3 3.75 1.64 2.74 131.46 295.79 0.00 184.87 111.49

4 5.00 2.19 3.83 295.79 525.85 0.00 328.66 111.59

5 6.25 2.74 4.93 525.85 821.64 0.00 513.52 111.68

6 7.50 3.29 6.03 821.64 1183.16 0.00 739.47 111.78

7 8.75 3.83 7.12 1183.16 1610.41 0.00 1006.51 111.87

8 10.00 4.38 8.22 1610.41 2103.39 0.00 1314.62 111.97

9 11.25 4.93 9.31 2103.39 2661.75 0.01 1663.60 112.07

10 12.50 5.48 10.41 2661.75 3283.91 0.03 2052.46 112.18

11 13.75 6.03 11.50 3283.91 3969.31 0.05 2480.85 112.29

12 15.00 6.57 12.60 3969.31 4718.72 0.06 2949.24 112.41

13 16.25 7.12 13.69 4718.72 5532.46 0.07 3457.83 112.54

14 17.50 7.67 14.79 5532.46 6410.70 0.08 4006.74 112.68

15 18.75 8.22 15.89 6410.70 7353.53 0.09 4596.01 112.82

16 20.00 8.76 16.98 7353.53 8361.04 0.10 5225.71 112.96

17 21.25 8.23 17.00 8361.04 9368.64 0.11 5855.46 113.11

18 22.50 7.69 15.92 9368.64 10310.71 0.11 6444.26 113.23

19 23.75 7.14 14.82 10310.71 11186.32 0.12 6991.52 113.35

20 25.00 6.59 13.73 11186.32 11995.58 0.12 7497.31 113.46

21 26.25 6.04 12.63 11995.58 12738.56 0.13 7961.68 113.55

22 27.50 5.50 11.54 12738.56 13415.35 0.13 8384.68 113.64

23 28.75 4.95 10.44 13415.35 14026.00 0.13 8766.34 113.71

24 30.00 4.40 9.35 14026.00 14570.57 0.14 9106.69 113.78

25 31.25 3.85 8.25 14570.57 15049.11 0.14 9405.78 113.84

26 32.50 3.30 7.16 15049.11 15461.66 0.14 9663.63 113.88

27 33.75 2.76 6.06 15461.66 15808.27 0.14 9880.26 113.93

28 35.00 2.21 4.96 15808.27 16088.97 0.14 10055.70 113.96

29 36.25 1.66 3.87 16088.97 16303.81 0.14 10189.97 113.98

30 37.50 1.11 2.77 16303.81 16452.82 0.15 10283.11 114.00

31 38.75 0.57 1.68 16452.82 16536.04 0.15 10335.12 114.01

32 40.00 0.02 0.58 16536.04 16553.51 0.15 10346.03 114.01

33 41.25 0.00 0.02 16553.51 16537.05 0.15 10335.75 114.01

34 42.50 0.00 0.00 16537.05 16519.55 0.15 10324.81 114.01

35 43.75 0.00 0.00 16519.55 16502.06 0.15 10313.88 114.01

36 45.00 0.00 0.00 16502.06 16484.58 0.15 10302.96 114.01

37 46.25 0.00 0.00 16484.58 16467.11 0.15 10292.04 114.00

38 47.50 0.00 0.00 16467.11 16449.65 0.15 10281.12 114.00

39 48.75 0.00 0.00 16449.65 16432.20 0.15 10270.22 114.00

40 50.00 0.00 0.00 16432.20 16414.76 0.15 10259.32 114.00

41 51.25 0.00 0.00 16414.76 16397.33 0.15 10248.42 114.00

42 52.50 0.00 0.00 16397.33 16379.90 0.15 10237.53 113.99

43 53.75 0.00 0.00 16379.90 16362.49 0.15 10226.65 113.99

44 55.00 0.00 0.00 16362.49 16345.08 0.15 10215.77 113.99

45 56.25 0.00 0.00 16345.08 16327.69 0.14 10204.89 113.99

46 57.50 0.00 0.00 16327.69 16310.30 0.14 10194.03 113.99

47 58.75 0.00 0.00 16310.30 16292.92 0.14 10183.17 113.98

48 60.00 0.00 0.00 16292.92 16275.55 0.14 10172.31 113.98

49 61.25 0.00 0.00 16275.55 16258.19 0.14 10161.46 113.98

50 62.50 0.00 0.00 16258.19 16240.84 0.14 10150.62 113.98

51 63.75 0.00 0.00 16240.84 16223.50 0.14 10139.78 113.98

52 65.00 0.00 0.00 16223.50 16206.17 0.14 10128.95 113.97

53 66.25 0.00 0.00 16206.17 16188.85 0.14 10118.12 113.97

54 67.50 0.00 0.00 16188.85 16171.54 0.14 10107.30 113.97

55 68.75 0.00 0.00 16171.54 16154.23 0.14 10096.49 113.97

56 70.00 0.00 0.00 16154.23 16136.94 0.14 10085.68 113.96

57 71.25 0.00 0.00 16136.94 16119.65 0.14 10074.87 113.96

58 72.50 0.00 0.00 16119.65 16102.38 0.14 10064.07 113.96

59 73.75 0.00 0.00 16102.38 16085.11 0.14 10053.28 113.96

60 75.00 0.00 0.00 16085.11 16067.85 0.14 10042.50 113.96

61 76.25 0.00 0.00 16067.85 16050.60 0.14 10031.72 113.95

62 77.50 0.00 0.00 16050.60 16033.36 0.14 10020.94 113.95

63 78.75 0.00 0.00 16033.36 16016.13 0.14 10010.17 113.95

64 80.00 0.00 0.00 16016.13 15998.91 0.14 9999.41 113.95

65 81.25 0.00 0.00 15998.91 15981.70 0.14 9988.65 113.95

66 82.50 0.00 0.00 15981.70 15964.50 0.14 9977.90 113.94

67 83.75 0.00 0.00 15964.50 15947.30 0.14 9967.15 113.94

68 85.00 0.00 0.00 15947.30 15930.12 0.14 9956.41 113.94

69 86.25 0.00 0.00 15930.12 15912.95 0.14 9945.68 113.94

70 87.50 0.00 0.00 15912.95 15895.78 0.14 9934.95 113.94

71 88.75 0.00 0.00 15895.78 15878.63 0.14 9924.23 113.93

72 90.00 0.00 0.00 15878.63 15861.48 0.14 9913.52 113.93

73 91.25 0.00 0.00 15861.48 15844.35 0.14 9902.81 113.93

74 92.50 0.00 0.00 15844.35 15827.22 0.14 9892.10 113.93

75 93.75 0.00 0.00 15827.22 15810.10 0.14 9881.40 113.93

76 95.00 0.00 0.00 15810.10 15793.00 0.14 9870.71 113.92

77 96.25 0.00 0.00 15793.00 15775.90 0.14 9860.03 113.92

78 97.50 0.00 0.00 15775.90 15758.81 0.14 9849.35 113.92

79 98.75 0.00 0.00 15758.81 15741.73 0.14 9838.67 113.92

80 100.00 0.00 0.00 15741.73 15724.66 0.14 9828.00 113.92

81 101.25 0.00 0.00 15724.66 15707.60 0.14 9817.34 113.91

82 102.50 0.00 0.00 15707.60 15690.55 0.14 9806.69 113.91

83 103.75 0.00 0.00 15690.55 15673.51 0.14 9796.03 113.91

84 105.00 0.00 0.00 15673.51 15656.48 0.14 9785.39 113.91

85 106.25 0.00 0.00 15656.48 15639.46 0.14 9774.75 113.91

86 107.50 0.00 0.00 15639.46 15622.45 0.14 9764.12 113.90

87 108.75 0.00 0.00 15622.45 15605.45 0.14 9753.49 113.90

88 110.00 0.00 0.00 15605.45 15588.45 0.14 9742.87 113.90

89 111.25 0.00 0.00 15588.45 15571.47 0.14 9732.26 113.90

90 112.50 0.00 0.00 15571.47 15554.49 0.14 9721.65 113.90

91 113.75 0.00 0.00 15554.49 15537.53 0.14 9711.04 113.89

92 115.00 0.00 0.00 15537.53 15520.57 0.14…