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HomeMy WebLinkAbout20080845 Ver 1_More Info Received_20080728r ??rS LETTER OF TRANSMITTAL STEWART TO Q? - o82f5 FROM Cyndi Karoly, Supervisor Adam Pike 401 Oversight/Express Review Permitting Unit Project Engineer 2321 Crabtree Boulevard, Suite 250 (919) 8664805 Raleigh, NC 27699 919-733-1786 DATE SENT VIA July 11, 2008 UPS Ground PROJECT NUMBER PROJECT NAME C7005 White Deer Park COPIES DATE DESCRIPTION 5 7/11/08 supplemental plan sheets 5 7/11/08 Response to Comments 5 7/11/08 Revised SIA For approval ? For review & comment Returned for corrections For your use ? Approved as submitted Returned after review As requested ? Approved as noted Resubmit copies for approval COMMENTS Cyndi, attached is the additional information you requested. Please do not hesitate to call if you have any questions. Thanks. i SIGNED ' }{- _ JUG 9 2008 l"JETt ADENR - WATER QLIAU y NDS AND STORHA%T?R OUNCH COPIED TO White Deer Park Garner, NC The following are the review comments and corrections for the above referenced plan (comment received from DWQ on July 3, 2008): 1. Pleas show the locations of all stormwater discharge points on the plans. The stormwater that is being treated by the bioretention areas is meeting the diffuse flow requirements associated with the Neuse Riparian Buffer Rule. If there are any additional stormwater discharge points, diffuse flow will need to be established in these locations in accordance with Chapter 8 of the BMP Manual. Please provide the appropriate documentation on the diffuse flow measures that will be used (i.e. either a BMP Supplement Form or proof of Town of Garner's approval of a BMP system). Response: Please see sheets C500 - C503 for locations of all discharge points from the site. Please also see associated calculations for listing of discharge points and values. Included also is sets of plans approved by the Town of Garner. 2. Since the bioretention areas are being used to meet the state's diffuse flow requirements, please provide documentation of the Town of Garner's approval of the stormwater management plan for this project by providing either: • A valid approval letter from the Town of Garner indicating that the proposed activity has an approved SMP and one copy of the approved SMP, including plan details, calculations and other supporting information, OR • A set of stormwater plan details and calculations stamped as "Approved" by the Town of Garner. White Deer Park Garner, NC The following are the review comments and corrections for the above referenced plan (comment received from DWQ on July 3, 2008): Pleas show the locations of all stormwater discharge points on the plans. The stormwater that is being treated by the bioretention areas is meeting the diffuse flow requirements associated with the Neuse Riparian Buffer Rule. If there are any additional stormwater discharge points, diffuse flow will need to be established in these locations in accordance with Chapter 8 of the BMP Manual. Please provide the appropriate documentation on the diffuse flow measures that will be used (i.e. either a BMP Supplement Form or proof of Town of Garner's approval of a BMP system). Response: Please see sheets C500 - C503 for locations of all discharge points from the site. Please also see associated calculations for listing of discharge points and values. Included also is sets of plans approved by the Town of Garner. 2. Since the bioretention areas are being used to meet the state's diffuse flow requirements, please provide documentation of the Town of Garner's approval of the stormwater management plan for this project by providing either: • A valid approval letter from the Town of Garner indicating that the proposed activity has an approved SMP and one copy of the approved SMP, including plan details, calculations and other supporting information, OR • A set of stormwater plan details and calculations stamped as "Approved" by the Town of Garner. White Deer Park Garner, NC The following are the review comments and corrections for the above referenced plan (comment received from DWQ on July 3, 2008): Pleas show the locations of all stormwater discharge points on the plans. The stormwater that is being treated by the bioretention areas is meeting the diffuse flow requirements associated with the Neuse Riparian Buffer Rule. If there are any additional stormwater discharge points, diffuse flow will need to be established in these locations in accordance with Chapter 8 of the BMP Manual. Please provide the appropriate documentation on the diffuse flow measures that will be used (i.e. either a BMP Supplement Form or proof of Town of Garner's approval of a BMP system). Response: Please see sheets C500 - C503 for locations of all discharge points from the site. Please also see associated calculations for listing of discharge points and values. Included also is sets of plans approved by the Town of Garner. 2. Since the bioretention areas are being used to meet the state's diffuse flow requirements, please provide documentation of the Town of Garner's approval of the stormwater management plan for this project.by providing either: • A valid approval letter from the Town of Garner indicating that the proposed activity has an approved SMP and one copy of the approved SMP, including plan details, calculations and other supporting information, OR • A set of stormwater plan details and calculations stamped as "Approved" by the Town of Garner. White Deer Park Garner, NC The following are the review comments and corrections for the above referenced plan (comment received from DWQ on July 3, 2008): 1. Pleas show the locations of all stormwater discharge points on the plans. The stormwater that is being treated by the bioretention areas is meeting the diffuse flow requirements associated with the Neuse Riparian Buffer Rule. If there are any additional stormwater discharge points, diffuse flow will need to be established in these locations in accordance with Chapter 8 of the BMP Manual. Please provide the appropriate documentation on the diffuse flow measures that will be used (i.e. either a BMP Supplement Form or proof of Town of Garner's approval of a BMP system). Response: Please see sheets C500 - C503 for locations of all discharge points from the site. Please also see associated calculations for listing of discharge points and values. Included also is sets of plans approved by the Town of Garner. 2. Since the bioretention areas are being used to meet the state's diffuse flow requirements, please provide documentation of the Town of Garner's approval of the stormwater management plan for this project by providing either: • A valid approval letter from the Town of Garner indicating that the proposed activity has an approved SMP and one copy of the approved SMP, including plan details, calculations and other supporting information, OR • A set of stormwater plan details and calculations stamped as "Approved" by the Town of Garner. White Deer Park Garner, NC The following are the review comments and corrections for the above referenced plan (comment received from DWQ on July 3, 2008): 1. Pleas show the locations of all stormwater discharge points on the plans. The stormwater that is being treated by the bioretention areas is meeting the diffuse flow requirements associated with the Neuse Riparian Buffer Rule. If there are any additional stormwater discharge points, diffuse flow will need to be established in these locations in accordance with Chapter 8 of the BMP Manual. Please provide the appropriate documentation on the diffuse flow measures that will be used (i.e. either a BMP Supplement Form or proof of Town of Garner's approval of a BMP system). Response: Please see sheets C500 - C503 for locations of all discharge points from the site. Please also see associated calculations for listing of discharge points and values. Included also is sets of plans approved by the Town of Garner. 2. Since the bioretention areas are being used to meet the state's diffuse flow requirements, please provide documentation of the Town of Garner's approval of the stormwater management plan for this project by providing either: • A valid approval letter from the Town of Garner indicating that the proposed activity has an approved SMP and one copy of the approved SMP, including plan details, calculations and other supporting information, OR • A set of stormwater plan details and calculations stamped as "Approved" by the Town of Garner. Stormwater Impact Analysis Construction Drawing Submittal For the proposed White Deer Park Garner, North Carolina Prepared for OBS Landscape Architects Land Planners Prepared By Stewart Engineering, Inc. S STEWART March 20, 2008 Revised April 28, 2008 Revised May 30, 2008 Revised July 11, 2008 TOWN OF GARNER ENGINEERING PLANS APPROVED ?. ----- s •I/t SIGNED ? DATE GEe., 0Wff, JUL e ? 2??g DENR WATER QUALIFY WETLANDS AND STDRibf l MTER BRANCH Stormwater Impact Analysis For White Deer Park Garner, North Carolina Prepared for: OBS Landscape Architects Land Planners Prepared by: Stewart Engineering, Inc. 421 Fayetteville Street, Suite 400 Raleigh, NC 27601 919.380.8750 CARP a SEAL "s 033317 .4 Qz- PRELIMINARY - FOR REVIEW PURPOSES ONLY Stewart Project No. C7005 March 20, 2008 Revised April 28, 2008 Revised May 30, 2008 Revised July 11, 2008 Stormwater Impact Analysis WHITE DEER PARK GARNER, NORTH CAROLINA EXECUTIVE SUMMARY This Stormwater Impact Analysis has been prepared specifically to address the requirements of the Town of Garner Stormwater Management Ordinance (Article 7, Section 7.2 of the Unified Development Ordinance), in order to quantify the impact of the proposed development upon downstream systems. Per the Town of Garner Stormwater Management Ordinance, the post-development peak flow rate for the 1-, 10-, 25-year, 24-hour storm events must be held to that of pre- development conditions. The Total Nitrogen Export for the site must also be held to 3.6 lb/ac/yr. As is detailed below, the post-development peak flow rate in each storm of interest remains equal to that of the per-development condition due to the large overall drainage basin (1304.71 ac). The pre-development Total Nitrogen Export is calculated as 2.17 Ib/ac/yr where as the post-development is to 2.16 lb/ac/yr. Given that the post-development export is less than 3.6 Ib/ac/yr without the use of BMPs, no buydown payment will be required for this project. Site Information The White Deer Park site is located at the intersection of Buffaloe and Aversboro Roads in Garner. The existing site is mostly wooded but does include two substantial open areas. The project site is located in the southeast corner of a 91.41 ac parcel with a project area of approximately 25.50 ac. Existing impervious area on the site is 0.38 ac. The site lies within the Neuse River Basin along with the Lake Benson Conservation District. Per FEMA FIRMs 372017000] and 3720171000), the site contains a 100-yr floodplain associated with a tributary to Reedy Creek. The Wake County Soil Survey Map indicates the soils on site consist primarily of Cecil sandy loams which are classified as Hydrologic Soil Group B. The project area also contains two existing intermittent streams, one of which runs long the northwest boundary of the project area and one that splits the project area from west to east. Both stream corridors will be protected with 50' Neuse River Buffers. Portions of each stream are also buffered with a 90' Lake Benson Watershed Conservation Buffer. Proposed Improvements The proposed development on the site will include a nature center (2500 sf), restrooms, learning terrace, picnic shelters, playground areas, entry drive, site roads, and parking lots. The site improvements will add 4.02 ac of additional impervious area for a total proposed impervious area of 4.40 ac or 4.81% (based upon parcel area). Stormwater from the majority of the proposed parking areas will be captured and treated in one of four bioretention areas. Each bioretention area has been sized to capture the portion of parking area which drains to it and is equipped with underdrains. As is described in the Design Procedure and Overall Results portions of this report, these BMPs are not required to meet either the Peak Flow or Nitrogen Export portions of the Town of Garner Stormwater Management Ordinance. Design Procedure The analysis point for the Peak Flow Analysis portion of the report is taken as the point where drainage from the project area leaves the site. This point happens to be the point at which the tributary to Reedy Creek existing the parcel (along the southwestern property boundary). The total drainage area (including offsite areas) to this point is approximately 1305 ac. The peak flow at this point is determined by using the SCS Hydrograph Formulation Method. The cover conditions for the project area is based upon the actual site conditions where as the offsite areas are based upon their current zoning. The Time of Concentration for the drainage area is determined using the method outlined in USDA TR-55. Due to the fact that the overall drainage area is significantly large in comparison to the project area, the increase in impervious area caused by development of the site does not increase the Curve Number. The Time of Concentration remains the same as well. Therefore, there is no increase in peak flow at the point of discharge off the site. The pre- and post-development Total Nitrogen Export is calculated for the parcel area using the Town of Garner worksheet. Overall Results The results from the peak flow analysis and Total Nitrogen Export calculations are below. Note that the peak flow analysis is based upon the overall drainage area and associated cover conditions where as the Total Nitrogen Export calculations are based upon the parcel area. Please see the corresponding appendices for detailed calculations. Peak Flow Analysis The table below shows the pre and post-development peak flow for the 1-, 10-, and 25-year, 24-hour storm events. As is shown, the peak flow in the post- development condition is equal to that of the pre-development condition for each storm event. PP_ak Flnw Analvcic Drainage Area Curve Number 1-yr Peak Flow Percent Increase 10-Yr Peak Flow Percent Increase 25-yr Peak Flow Percent Increase ac cfs cfs cfs Existin Pro o d 91.41 91 41 70 261.83 974.10 1416.41 p se . 70 261.83 0.00% 974.10 0.00% 1416.41 0.00% The pre-development Total Nitrogen Export for the parcel (91.41 ac) is 2.17 Ib/ac/yr with a post-development export of 2.16 lb/ac/yr. This is below the allowable export of 3.6 lb/ac/yr. Diffuse Flow Narrative As stated above, the project does not require mitigation of stormwater quality or quantity, but due to the type of project (environmental education park) the Town of Garner is installing Bio-retention ponds for the parking area increase in impervious. These ponds will outfall as shown on the plans through rip rap and due to the low flow and length to the buffer there is sufficient diffused flow from these outfalls to not require level spreaders. There are also 7 additional outflows associated with the roadway improvements, playground area, an area drain near the nature center, and area drain near the picnic area that also have a low flow that should not require any additional measures for energy dissipation. (See table below) Outlet 10 yr storm velocity (fps) 10 yr storm flow (cfs) Distance to Channel FES 1 (roadway catch basin 3.5 .74 273' of natural woods outlet) sloped @ 5.7% FES 2 (roadway catch basin 4.33 2.5 400' of grassed channel outlet) sloped @ 4.24% to 138' of natural woods sloped 5.7% FES 3 (Bio-retention ponds A 3.24 5.73 190' of natural woods & B) sloped @ 8.9% FES 4 (Bio-retention ponds C 4.4 7.79 210' of natural woods & D) sloped @ 8% Playground outfall 1 3.0 0.32 350' of grassed channel sloped @ 6.8% Playground outfall 2 4.14 0.15 423' of grassed channel sloped @ 5.7% Playground outfall 3 3.10 .61 205' of natural woods sloped @ 6.7% Nature Center Outfall 2.05 .03 372' of natural woods sloped @ 6.7% Picnic Outfall 5.55 1.55 437' of natural woods sloped @ 7.3% Conclusions Based upon the results of this analysis shown above, the requirements Town of Garner Stormwater Management Ordinance as it pertains to Peak Flow and Total Nitrogen Export have been met for this project with no structural measures. Site Information TopoZone - USGS Lake Wheeler (NC) Topo Map topozone : 9 11 ¦ SITE P ++? I ? gk Page 1 of 1 v V.1 o.Z 0.3 0.4 0.5 km G 0 0.09 0.18 0.27 0.36 0.45 mi UTM 17 714799E 3950728N (NAD83/WGS84) USGS Lake Wheeler (NC) Quadrangle M__8 795 Projection is UTM Zone 17 NAD83 Datum G--1.385 http://www.topozone.com/print.asp?lat=35.67708&lon=-78.62658&s=24&size=l&u=4&layer=DRG25 &d... 3/18/2008 0 D A O r z D I N 2 m m -i z c rn m m 00 rn 5000 4000 3000 2000 1000 0 5000 Feet - \!?v y Scale 1:15840 a Scale I: I Mile O f ? x m 0 O C Z (1 D O r 2 2 m m CC 3 00 mm A V 00 3 3 Q 5 W CIO ° WL L M -. P a $ ° o O ,n V N m I ° ' M - + r, t ;j u 00 Appendix 1 Peak Flow Analysis - 1-, 10-1 & 25-year Storm Events (based upon total drainage area) STEWART Site Data Information Project: White Deer Park Number: C7005 Date: 20-Mar-08 Existing Site Conditions (Parcel Only) Soils Classification - Cecil Sandy Loam Hydrologic Soil Group - B FYTCTTNG n0ATAlA/7C AnMA _ nAft- Cover Area sf Area ac CN Impervious Bldg 0 0.00 Road 6559 0.15 Sidewalk 0 0.00 TotalIm 16386 0.38 98 Open 619859 14.23 69 Wooded 3345477 76.80 60 awo1/LL V1.41 bZ i V IAL EXI STING DRA INAGE AR EA Coves , Ares s Rr ac ?g CN Impervious Bldg 0.00 Road 0.15 Sidewalk 0.00 Total Im ! 0.38 98 Q erg 619859 14.23 69 ended 76.80 60 R-12 1166:41 70 R-40 46.89 85 PDADnCFn nDATMArC AoCA _ nwr. e.r. Cover Area sf Area ac ` CN Impervious Bldg 11776 0.27 Parkin 95051 2.18 Sidewalk 85025 1.95 Total Imp 191852 4.40 98 Open 536177 12.31 69 Wooded 3253693 74.69 60 L. 3wo1/Zc V1.41 b3 TOTAL PROPOSED DRAINAGE AR Cover Are1a . fs Area ac CN Im eriris 61d y,., ?:1 77(i 0.27 Road pro;' "x 96tf61 `> 2.16 SI€? t Rk 85025 1:95 TOMEixt ` 191852 4.4Q 98 Q 813 y,- 536177 12:31 69 ?,aed 32$3693 74.69 hQ FYTCTTNG nDATRIAGC AOCA _ 0%000 - Zoning Area sf Area ac CN R-12 50809010 1166.41 70 R-40 2042379 46.89 85 I W IMF 7LO713ify 1L13.su 71 DDnDnCCn nDATMAn_C An- Zoning Area s Area ac CN R-12 50809010 1166.41 -70- R-40 2042379 46.89 85 ?+..".? JipJ iJO7 iG13.3U /1 -22-, 50$09010 1166.41 76 R-40 2042,379 ` 4Fz.S9 85 TOTAL 56833111 1304.71 70 421 Fayetteville St., Suite 400, Raleigh, NC 27601 Tel 919.380.8750 Fax 919.380.8752 www.stewart-eng.com TR55 Tc Worksheet Hydraflow Hydrographs by Intelisolve Hyd. No. 1 Total Existing Description A B C Totals Sheet Flow Manning's n-value = 0.011 0.011 0.011 Flow length (ft) = 100.0 0.0 0.0 Two-year 24-hr precip. (in) = 3.60 0.00 0.00 Land slope (%) = 2.70 0.00 0.00 Travel Time (min) = 1.01 + 0.00 +' 0.00 = 1.01 Shallow Concentrated Flow Flow length (ft) = 1526.00 0.00 0.00 Watercourse slope (%) = 2.12 0.00 0.00 Surface description = Unpaved Paved Paved Average velocity (fUs) = 2.35 0.00 0.00 Travel Time (min) = 10.83 + 0.00 + 0.00 = 10.83 Channel Flow X sectional flow area (sqft) = 63.00 0.00 0.00 Wetted perimeter (ft) = 32.00 0.00 0.00 Channel slope (%) = 0.78 0.00 0.00 Manning's n-value = 0.080 0.015 0.015 Velocity (ft/s) = 2.59 0.00 0.00 Flow length (ft) = 13868.0 0.0 0.0 Travel Time (min) = 89.25 + 0.00 + 0.00 89.25 Total Travel Time, Tc ......................................... ....................... .............. 101.10 min TR55 Tc Worksheet Hydraflow Hydrographs by. Intelisolve Hyd. No. 2 Total Proposed Description A B C Totals Sheet Flow Manning's n-value = 0.011 0.011 0.011 Flow length (ft) = 100.0 0.0 0.0 Two-year 24-hr precip. (in) = 3.60 0.00 0.00 Land slope (%) = 2.70 0.00 0.00 Travel Time (min) = 1.01 + 0.00 + 0.00 = 1.01 Shallow Concentrated Flow Flow length (ft) = 1526.00 0.00 0.00 Watercourse slope (%) = 2.12 0.00 0.00 Surface description = Unpaved Paved Paved Average velocity (ft/s) = 2.35 0.00 0.00 Travel Time (min) = 10.83 + 0.00 + 0.00 10.83 Channel Flow X sectional flow area (sqft) = 63.00 0.00 0.00 Wetted perimeter (ft) = 32.00 0.00 0.00 Channel slope (%) = 0.78 0.00 0.00 Manning's n-value = 0.080 0.015 0.015 Velocity (ft/s) = 2.59 0.00 0.00 Flow length (ft) = 13868.0 0.0 0.0 Travel Time (min) = 89.25 + 0.00 + 0.00 = 89.25 Total Travel Time, Tc ................................................................ .............. 101.10 min Hydrograph Return Period Recap Hyd. N Hydrograph t Inflow H d Peak Outflow (cfs) Hydrograph o. ype (origin) y (s) 1-Yr 2-Yr 3-Yr 5-Yr 10-Yr 25-Yr 50-Yr 100-Yr description 1 2 SCS Runoff SCS Runoff ----- ------- 261.83 261.83 ------ ------ ----- --- ------ ------- 974.10 974.10 1416.41 1416.40 ------ ----- ------ ---- Total Existing Total Proposed Proj, file: 2008.03.19-C7005.gpw Thursday, Mar 20 2008, 10:14 AM Hydraflow Hydrographs by lntelisolve Hydrograph Summary Report Hyd. No. Hydrograph type (origin) Peak flow (cfs) Time interval (min) Time to peak (min) Volume (cuft) Inflow hyd(s) Maximum elevation (ft) Maximum storage (cuft) Hydrograph description 1 SCS Runoff 261.83 10 .790 3,443,235 ---- ----- ------ Total Existing 2 SCS Runoff 261.83 10 790 3,443,208 - ----- ------ Total Proposed 2008.03.19-C7005.gpw Return Period: 1 Year Thursday, Mar 20 2008, 10:14 AM Hydraflow Hydrographs by Intelisolve Hydrograph Plot Hydraflow Hydrographs by Intelisolve Hyd. No. 1 Total Existing Hydrograph type = SCS Runoff Storm frequency = 1 yrs Drainage area = 1304.700 ac Basin Slope = 0.0% Tc method = TR55 Total precip. = 3.00 in Storm duration = 24 hrs Thursday, Mar 20 2008, 10:14 AM Peak discharge = 261.83 cfs Time interval = 10 min Curve number = 70 Hydraulic length = Oft Time of conc. (Tc) = 101.10 min Distribution = Type II Shape factor = 484 Total Existing Q (cfs) Hyd. No. 1 -- 1 Yr 280.00 _............ ..._....._....._ ........................ _._......................... ....... .......................... . _........ ................................ ..........._ ........................... __.... 240.00 200.00 ........................ ................................ .......................... ............................. ..:.................... ......... ............................. ........ ............................ .............. .......:.............. ......... 160.00 ................ ....................::.., ..._...__.._................... ................ :......_. _..:............. ...... 120.00 ............_ ........... ..._................ ............ ...... .... .._._........................ .__..:......... .................._....... _............. ......:... ........... ......................................... .....:....................... ............._.... ....... ...................... ..__...... ..:.................... .... ._........_............_........... ......... ....... .......... ................... ._ ...:.. ............ 80.00 ........ _. ............ .. ........ ................. . 40.00 ....... .. . 0.00 Hydrograph Volume = 3,443,235 cuft Q (cfs) 280.00 .................................................................. 240.00 200.00 ................ ...........:.....................:.......................... ..... ...... - .................................................................................... . 160.00 120.00 ..................... _.......... ..... ..... .....__......_........................ .........._._ ............................. . 80.00 ............... ..._.._.... ._.._.:... 40.00 0 00 20 23 27 Time (hrs) Hydrograph Plot Hydraflow Hydrographs by Intelisolve Thursday, Mar 20 2008, 10:14 AM Hyd. No. 2 Total Proposed Hydrograph type = SCS Runoff Peak discharge = 261.83 cfs Storm frequency = 1 yrs Time interval = 10 min Drainage area = 1304.690 ac Curve number = 70 Basin Slope = 0.0% Hydraulic length = Oft Tc method = TR55 Time of conc. (Tc) = 101.10 min Total precip. = 3.00 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 Hydrograph Volume = 3,443,208 cult Q ( Total Proposed cfs) Hyd. No. 2 -- 1 Yr Q (cfs) 280.00 240.00 200.00 160.00 120.00 80.00 40.00 0.00 280.00 240.00 200.00 160.00 120.00 80.00 40.00 n nn Hydrograph Summary Report Hyd. No. Hydrograph type (origin) Peak flow (cfs) Time interval (min) Time to peak (min) Volume (cuft) Inflow hyd(s) Maximum elevation (ft) Maximum storage (cult) Hydrograph description 1 SCS Runoff 974.10 10 780 10,828,350 ---- ------ ---- Total Existing 2 SCS Runoff 974.10 10 780 10,828,270 - ---- ----- Total Proposed 2008.03.19-C7005.gpw Return Period: 10 Year Thursday, Mar 20 2008, 10:14 AM Hydraflow Hydrographs by Intelisolve Wx,r lrnnr--%r.h OIr%4 Hydraflow Hydrographs by Intelisolve Hyd. No. 1 Total Existing Hydrograph type = SCS Runoff Storm frequency = 10 yrs Drainage area = 1304.700 ac Basin Slope = 0.0% Tc method = TR55 Total precip. = 5.28 in Storm duration = 24 hrs Thursday, Mar 20 2008, 10:14 AM Peak discharge = 974.10 cfs Time interval = 10 min Curve number = 70 Hydraulic length = Oft Time of conc. (Tc) = 101.10 min Distribution = Type II Shape factor = 484 Hydrograph Volume = 10,828,350 cuft Total Existing Q (cfs) Hyd. No. 1 - 10 Yr 980.00 .... _ .......... ................. ................ ...._......_...................._.._...................... ...._.................... .......... ..__............._.............................. .............. .... ...... ......... 840.00 Q (cfs) 980.00 840.00 Hydrograph Plot Hydraflow Hydrographs by Intelisolve Hyd. No. 2 Total Proposed Hydrograph type = SCS Runoff Storm frequency = 10 yrs Drainage area = 1304.690 ac Basin Slope = 0.0% Tc method = TR55 Total precip. = 5.28 in Storm duration = 24 hrs Q (cfs) 980.00 840.00 700.00 560.00 420.00 280.00 140.00 0.00 Thursday, Mar 20 2008, 10:14 AM Peak discharge = 974.10 cfs Time interval = 10 min Curve number = 70 Hydraulic length = 0 ft Time of conc. (Tc) = 101.10 min Distribution = Type II Shape factor = 484 Total Proposed Hyd. No. 2 - 10 Yr Q (cfs) r 980.00 Hydrograph Volume = 10,828,270 cuft 840.00 700.00 560.00 420.00 280.00 140.00 n nn Hydrograph Summary Report Hyd. No. Hydrograph type (origin) Peak flow (cfs) Time interval (min) Time to peak (min) Volume (cuft) Inflow hyd(s) Maximum elevation (ft) Maximum storage (cuft) Hydrograph description 1 SCS Runoff 1416.41 10 780 15,381,800 -- ----- ------ Total Existing 2 SCS Runoff 1416.40 10 780 15,381,680 ---- ----- ----- Total Proposed 2008.03.19-C7005.gpw Return Period: 25 Year Thursday, Mar 20 2008, 10:14 AM Hydraflow Hydrographs by Intelisolve Hydrograph Plot Hydraflow Hydrographs by Intelisolve Hyd. No. 1 Total Existing Hydrograph type = SCS Runoff Storm frequency = 25 yrs Drainage area = 1304.700 ac Basin Slope = 0.0% Tc method = TR55 Total precip. = 6.48 in Storm duration = 24 hrs Q (cfs) 1421.00 1218.00 1015.00 812.00 609.00 406.00 203.00 0.00 Total Existing Hyd. No. 1 -- 25 Yr Thursday, Mar 20 2008,10:15 AM Peak discharge = 1416.41 cfs Time interval = 10 min Curve number = 70 Hydraulic length = Oft Time of conc. (Tc) = 101.10 min Distribution = Type II Shape factor = 484 Hydrograph Volume = 15,381,800 cuft Q (cfs) 1421.00 1218.00 1015.00 812.00 609.00 406.00 203.00 n nn Hydrograph Plot. Hydraflow Hydrographs by Intelisolve Thursday, Mar 20 2008, 10:15 AM Hyd. No. 2 Total Proposed Hydrograph type = SCS Runoff Peak discharge = 1416.40 cfs Storm frequency = 25 yrs Time interval = 10 min Drainage area = 1304.690 ac Curve number = 70 Basin Slope = 0.0% Hydraulic length = Off Tc method = TR55 Time of conc. (Tc) = 101.10 min Total precip. = 6.48 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 Hydrograph Volume = 15,381,680 cult Q (cfs) Total Proposed Hyd. No. 2 -- 25 Yr Q (cfs) 1421.00 1421.00 ........................................ . 1218.00 1218.00 1015.00 1015.00 .................................. .... .......... ............................... ......... ................... .............._..........._................. ........... ...... ........._................. ........._ ................................ ........:...._.................... ..........._...._: 812.00 812.00 609.00 609.00 .......... ... ....... ............... _......_ ............................. ............_..........._..........._....... ..... .......... ....................................... ...._......................... ........._ _..................... ................... ................. ....:_.......:............ .... 406.00 406.00 203.00 203.00 0.00 _ n nn Appendix 2 Total Nitrogen Export (based upon parcel area) STEWART Site Data Analysis - Nitrogen Calculations (Based upon total Parcel Area) Existing Conditions Existing forest land 75.80 ac Existing pasture 14.23 ac Existing residential 0.00 ac Existing cropland 0.00 ac Existing commercial/industrial 0.38 ac Total Project Area 91.41 ac Proposed Conditions Protected Open 0.00 ac Managed Open 87.01 ac Impervious 4.40 ac Total Project Area 91.41 ac µ ;....c. _ STEWART Existing Nitrogen Runoff Calculations Total Parcel Step 1: Determine area for each type of land use and enter in Column (2). Step 2: Total the areas for each type of land use and enter at the bottom of Column (2). Step 3: Multiply the areas in Column (2) by the TN export Coefficients in Column (3) and enter in Column (4). Step 4: Total the TN exports for each type of land use and enter at the bottom of Column (4). Step 5: Determine the export coefficient for site by dividing the total TN export from uses at the bottom of Column (4) by the area at the bottom of Column (2). (1) Type of Land Cover (2) Areas (3) TN export coefficient (4) TN export from use (acres) (Ibs/ac/yr) (Ibs/yr) Existing forest land Existing pasture Existing residential Existing cropland Existing commercial/industrial 76.800 14.230 0.000 0.000 0.380 1.70 4.40 7.50 13.6 13 130.560 62.612 0.000 0.000 4.940 TOTAL A 91.410 -- 198.112 Total Nitrogen Export = 2.17 Ib/ac/yr STEWART Proposed Nitrogen Runoff Calculations Total Parcel Step 1: Determine area for each type of land use and enter in Column (2). Step 2: Total the areas for each type of land use and enter at the bottom of Column (2). Step 3: Multiply the areas in Column (2) by the TN export Coefficients in Column (3) and enter in Column (4). Step 4: Total the TN exports for each type of land use and enter at the bottom of Column (4). Step 5: Determine the export coefficient for site by dividing the total TN export from uses at the bottom of Column (4) by the area at the bottom of Column (2). (1) (2) (3) (4) Type of Land Cover Areas TN export coefficient TN export from use (acres) (Ibs/ac/yr) (Ibs/yr) Permanently protected 0.000 0.60 0.000 undisturbed open space (forest, unmown meadow) Permanently protected 87.010 1.2 104.412 open space (grass, landscaping, etc.) Impervious surfaces 4.400 21.2 93.280 (roads, parking lots, driveways, roofs, paved storage areas, etc.) TOTAL 91.410 --- 197.692 Nitrogen Control Plan - September 2007 Method 2: Commercial/IndustriaVResidential Sites with Known )impervious Area Project Name: White Deer Park Date: 3/20/08 Applicant: -Town of Garner Telephone: Part I. Riparian Buffers Does site contain riparian buffers? [ ] No Yes (show buffers on plan) [ ] Exempt (show basis for exemption) Part II. Nitrogen Calculation Item Proposed Site Information Area acres 1 Total project acreage 91.41 Ac 2 Total proposed impervious area 4.78 Ac 3 Existing impervious area (prior to 3/9/01 .38 Ac 4 New im ervious area Item 2 - Item 3 _ 4.40 Ac 5 Permanent) protected undisturbed open space [ _ 0.00 Ac 6 Permanently protected managed open space _ 87.01 Ac Pre-Develo me nt Loading Type of Land Cover Area (,-cres TN export coefficient lbs/ac/ r TN export from use (!bs/ r Existing forest land 76.80 _ 1.7 130.560 Existing pasture _ 14.23 4.4 _ 62.61 Existing residential 0.00 _ 7.5 _ 0.00 Existing cropland 0.00 13.6 0 00 Existing commercial/industrial 0.38 13 _- . 4.94 TOTAL 91.41 _ 198.12 Nitrogen Loading Rate' lbs/ac/ r 2.1 i Post-Development Loading before BMPs and/or Offset Payments Type of Land Cover Area TN export coefficient TN export from acres Ibs/ac/ r use lbs/ r Permanently protected undisturbed open space (forest, unmown meadow, wetlands, buffers Item 5 0.00 0 6 0.00 Permanently protected managed open space -(grass, landscaping, etc. tem 6 87.01 1.2 104.42 Impervious surfaces (roads, parking lots, driveways, roofs, paved storage areas, etc. Item 4 4.40 21.2 93.28 TOTAL 91.41 197.69 Item 7 Item 8) Nitrogen Loading Rate (lbs/ac/yr) (Equals Item 8 _ item 7) 2.16 BMP Type TN Removal Rate % Check which apply Wet Pond 25 Stormwater Wetland 40 Sand Filter 35 Bioretention 35 Grass Swale 20 Vegetated Filter Strip w/Level S reader 20 50' Restored or Additional Riparian buffer w/Level Spreader 30 D Detention 10 Post-Development Loading after BMPs and/or Offset Payments Item _ Description Iv5*_ro en Loading Rate lbs/ac/ r 9 Nitrogen load after BMPs show separately in detail N/A 10 Nitrogen load offset b payments Item 9 - 3.6 N/A Amount of Offset (Pounds of Nitrogen) [Item 10 x (Item 1- Item 3)] _N/A *To Calculate the Amount of the Nitrogen Offset Payment Required to Be Paid to the NC EEP Use The Following Formula: Amount of Offset Payment [Pounds of Nitrogen x $28.35 x 30 years] Part III. Control of Peak Stormwater Flow Calculated Pre-development Peak Flow (I-year) 261.83 CFS Calculated Post-development Peak Flow without Controls (I -year) 261.83 CFS Calculated Post-development Peak Flow with Controls (I-year) _ N/A Calculations and details showing control of nitrogen and peak stormwater runoff control must be included. Part IV: Watershed Development Permit I. Total project acreage (in Lake Benson Watershed) 91.41 Ac 2. Total proposed impervious surface (in Lake Benson Watershed) 4.40 Ac 3. Existing impervious surface (in Lake Benson Watershed) * .38 Ac 4. Equivalent project acreage (Item I - Item 3) 91.03 Ac _ 5. New impervious surface (Item 2 - Item 3) _ 4.02 Ac 6. Percent impervious [(Item 5 + Item 4) x 100] 4.41% * Limited to impervious surface existing before 7/1/93 I, the undersigned, certify that to the best of my knowledge that the above information is correct (affix seal) (sign) To be filled in by staff Project Watershed Protection Requirements ? Project Exempt: Explain ? Project Located in Lake Benson Conservation District - LBCD (Critical Area) Standards Apply ? Project Located Outside LBCD - On-site treatment required. ? Minor Variance Requested (WRB) Approved (date): Disapproved (date): ? Major Variance Requested (EMC) Approved (date): Disapproved (date): Recommended by WRB (circle one): YES NO Comments (use additional sheet if necessary) Appendix 3 Bioretention Sizing Calculations STEWART Bioretention Area Sizing BIO A (for 85% TSS removal) Project: White Deer Park Number: C7005 Date: 28-Apr-07 Drainage Basin Re uired Stora e for 1st inch of runoff Total Drainage Area = 17424 sf Simple Method Total Impervious Area = 13939 sf Percent Impervious = 80% Rv = 0.05 + 0.009(I) I = % impervious = 80% Rainfall Depth = 1 in Rv = 0.77 in Volume = 1118 cf Required u ace rea Ponding Depth = 9 in (max 12) Required Storage Vol = 1118 cf Minimum Surface Area = 1491 sf Average Length = 183 ft Average Width = 10 ft Surface Area provided = 1830 sf Design parameters from DENR Stormwater Best Management Pr *Per NCDENR Manual 3ctices Manual, October 2007 421 Fayetteville Street, Suite 400, Raleigh, NC 27601 Tel 919.380.8750 Fax 919.380.8752 www.stewart- eng.com STEWART Bioretention Area Sizing - BIO B (for 85% TSS removal) Project: White Deer Park Number: C7005 Date: 28-Apr-07 Drainage Basin Required Storag e for 1st inch of runoff Total Drainage Area = 20334 sf Simple Method Total Impervious Area = 15911 sf Percent Impervious = 78% Rv = 0.05 + 0.009(I) I = % impervious = 78% Rainfall Depth = 1 in Rv = 0.75 in Volume= 1278 cf Required Sur face Area Ponding Depth = 9 in (max 12) Required Storage Vol = 1278 cf Minimum Surface Area = 1704 sf Average Length = 171 ft Average Width = 10 ft surface Area provided = 1710 sf Design parameters from DENR Stormwater Best MananPmant Pr *Per NCDENR Manual jctices Manual, October 2007 421 Fayetteville Street, Suite 400, Raleigh, NC 27601 Tel 919.380.8750 Fax 919.380.8752 www.stewart- eng.com a- STEWART Bioretention Area Sizing - BIO C (for 85% TSS removal) Project: White Deer Park Number: C7005 Date: 28-Apr-07 Drainage Basin Required Storag e for 1st inch of runoff Total Drainage Area = 31467 sf Simple Method Total Impervious Area = 26527 sf Percent Impervious = 84% Rv = 0.05 + 0.009(I) I = % impervious = 84% Rainfall Depth = 1 in Rv = 0.81 in Volume= 2121 cf - e uire Sur face Area Ponding Depth = 9 in (max 12) Required Storage Vol = 2121 cf Minimum Surface Area = 2828 sf Average Length = 173 ft Average Width = 10 ft Surface Area provided = 1730 sf Design parameters from DENR Stnrmwatar Ract Mananamznt- Dr *Per NCDENR Manual :ices Manual, October 2007 421 Fayetteville Street, Suite 400, Raleigh, NC 27601 Tel 919.380.8750 Fax 919.380.8752 www.stewart- eng.com STEWART Bioretention Area Sizing - BIO D (for 85% TSS removal) Project: White Deer Park Number: C7005 Date: 28-Apr-07 Drainage Basin Required Storag e for 1st inch of runoff Total Drainage Area = 24584 sf Simple Method Total Impervious Area = 19595 sf Percent Impervious = 80% Rv = 0.05 + 0.009(I) I = % impervious = 80% Rainfall Depth = 1 in Rv = 0.77 in Volume= 1572 cf Required u ace Area Ponding Depth = 9 in (max 12) Required Storage Vol = 1572 cf Minimum Surface Area = 2096 sf Average Length = 178 ft Average Width = 10 ft Surface Area provided, = 1780sf Design parameters from DENR Stormwater Best Manaaement Pr *Per NCDENR Manual actices Manual, October 2007 Appendix 4 Bioretention operations and Maintenance Manual OPERATIONS AND MAINTENANCE MANUAL w... November 2004 ... BEST MANAGEMENT PRACTICES Garner, NC Project Name: White Deer Park Date: 3/20/08 Property Owner/Responsible Party: Town of Garner _ Address: _Pp %, 446 Garner Nr 27529-0446 Telephone: The maintenance of any Best Management Practice (BMP) installed to achieve nitrogen loading and/or flow attenuating requirements for a development shall be the responsibility of the property owner or other identified responsible party. In the case of residential or commercial subdivisions, Home Owners Associations or Merchants Associations must be established in order to identify the responsible party. This manual establishes general procedures for maintenance and operation of the allowed BMP types in accordance with the Town of Garner Stormwater Program for Nitrogen Control. It is important to note that only general maintenance tasks are identified here. All devices shall be maintained to original design standards. This agreement shall be signed and notarized by the responsible party to perform the tasks specified in the plan, including inspections, operation, and any needed maintenance activities. I. BMP Identify the types of BMPs located on the site and give a brief description on their design. If you need additional space please attach separate pages to this document. BMP Type Check which apply Brief Description Wet Pond Stormwater Wetland Sand Filter Bioretention Capturing drainage from proposed parking areas. Grass Swale Vegetated Filter Strip w/Level Spreader 50' Restored or Additional Riparian Buffer w/Level Spreader Dry Detention ??. ?.awallaviiNl\VV A. Wet Pond - Maintenance requirements are as follows: . 1. Debris and litter control checks for inlet, outlet, and orifice obstruction after every storm producing runoff. 2. Provisions for routine vegetation management/mowing and a schedule for these activities. 3. Checks every 6 months, or more frequently, for: a. Sediment buildup and the need for removal. b. Erosion along the bank and the need for reseeding or stabilization and, if reseeding is necessary, a reseeding schedule. c. Erosion at the inlet and outlet and methods of stabilization. d. Seepage through the dam. e. Operation of any valves or mechanical components. B. Stormwater Wetland - Maintenance requirements are as follows: 1. Wetlands will tend to collect debris, and it should be removed whenever it accumulates, or at least twice annually. 2. Wetlands should be inspected annually after a rain even to ensure that the basin is operating as designed. 3. At a minimum, items that should be included in the inspection are: a. Clogging of the outlet or too rapid a release. b. Erosion on the banks. c. Erosion at the inlet and outlet. d. Sediment accumulation and the need for removal. e. Condition of the emergency spillway. f. Woody vegetation in the embankment. C. Sand Filter - Maintenance requirements are as follows: 1. At least once a year each filter must be inspected after a storm to determine if the filter bed is passing the runoff as expected. 2. Maintenance operations must be performed when storms of approximately one inch are not passing through the filter within 24 hours. Maintenance consists of removing the first two or three inches of discolored sand, and replacing this with new sand. The sand that has been removed would then be dewatered, if necessary, and then landfilled. 3. At the same time that maintenance is performed on the sand chamber, the sediment chamber should also be pumped and cleaned. It is most likely that the sediment removed from the first chamber will need to be dewatered before it is allowed to be dumped at a landfill. D. Bioretention - Maintenance requirements are as follows: 1. Visually inspect and repair soil erosion on a monthly basis. 2. Remulch any void area whenever necessary. Replacement of mulch layers may be necessary every two or three years. Mulch should be replaced in the spring. When the mulch layer is replaced, the previous layer should be removed first. 3. Remove and replace all dead and diseased vegetation considered beyond treatment. This should be done twice a year, once in the spring and once in the fall. Treat all diseased trees and shrubs that are not beyond treatment as needed. Page 2 of 4 E. Grass Swale - Maintenance requirements are as follows: 1. At least once annually, remove excess sediment,especially from the upstream edge, to maintain original contours and grading. 2. At least once annually, repair any erosion and regrade the swale to ensure that the runoff flows evenly in a thin sheet through the swale. 3. At least once annually, inspect vegetation and revegetate the swale to maintain a dense growth of vegetation. 4. Grassed swales shall be mowed at least twice annually to a minimum height of six inches. F. Vegetated Filter Strip with Level Spreader - Maintenance requirements are as follows: 1. At least once annually, remove deposited sediment, especially from the upstream edge, to maintain original contours and grading. 2. Repair channels that form and regrade the filter strip to ensure that the runoff flows evenly in a thin sheet over the filter strip. 3. Repair level spreader whose disrepair can cause the formation of channels in the filter strip. 4. Reseed and regrade the filter strip to maintain a dense growth of vegetation, especially if the strip has been used for sediment control. 5. Grassed filter strips shall be mowed at least twice annually to a minimum height of six inches. G. 50' Restored or Additional Riparian Buffer with Level Spreader - Restored or additional riparian buffers used for nitrogen reduction should be left in an undisturbed condition. Only maintenance activities allowed by the buffer rules would be allowed. Any level spreaders used to diffuse flow into the buffer should be maintained as required in section II.F. H. Dry Detention Maintenance requirements are as follows: a. All grassed areas of a dry detention basin should be mowed at least twice annually. b. Dry detention basins will tend to collect debris, and it should be removed whenever it accumulates, or at least twice annually. c. Pond should be inspected annually after a rain event to ensure that the basin is operating as designed. 4. At a minimum, items that should be included in the inspection are: a. Clogging of the outlet or too rapid a release. b. Erosion on the banks. c. Erosion at the inlet and outlet. d. Sediment accumulation and the need for removal. e. Condition of the emergency spillway. f. Woody vegetation in the embankment. The Town will inspect BMPs on an annual basis and forward a list of any required deficiencies or repairs to the property owner/responsible party. The property owner/responsible party will have 90 days to correct all deficiencies and make all repairs to the satisfaction of the Town Engineer. Failure to satisfactorily complete the repairs within the 90 days will cause the BMP to be declared a nuisance as provided for in Section 6-17 of the Garner Town Code. Abatement of the nuisance will proceed as provided for in Chapter 6, Article II of the Garner Town Code. Page 3 of 4 STORMWATER BEST MANAGEMENT PRACTICES OPERATIONS AND MAINTENANCE AGREEMENT Property Owner/Responsible Party Sign: Print: LANDSCAPING COMMENTS Please contact Jennifer Collins, Urban Design Specialist at 772-4688 regarding the attached landscaping comments. ENGINEERING DEPARTMENT Please contact Frank Powell, the Town Engineer at 772-4688 regarding the attached engineering comments. PUBLIC UTILITIES Please contact Danielle Barber, with the City of Raleigh, at 831-6162 regarding the public utilities comments. PUBLIC WORKS Please contact Paul Cox at 772-7600 regarding the attached public works comments. BUILDING AND FIRE INSPECTIONS Please contact Les Harmon in the Building Inspections Department at 772-4688 regarding the attached inspections comments. Please note the following fees. Please review with the appropriate departments to determine the amount and if applicable for this project. PLANNING FEES BUILDING PERMIT ENGINEERING FEES: FEES Master Sign Plan Building Permit Utility Development Fees Sign Permit Garbage Container, Sewer Capacity Replacement Fees Final Plat Meter Fees Water Capacity Replacement Fees Subdivision Exemption Water Tap Fee Fee-In-Lieu of Nitrogen Reduction Easement Dedication Sewer Tap Fee Maintenance Fee Sewer Acreage Fee Street Inspection Fees Water Acreage Fee Street Signs Engineering Tap Inspection Fees c: Jennifer Collins, Urban Design Specialist Danielle Barber, City of Raleigh Brad Bass, Planning Director Paul Cox, Public Works Jaclyn Sumner, Engineering Sandy Teal & Les Harmon, Building Inspection Frank Powell, PE, Town Engineer Jenny Saldi, Senior Planner H:1PLA-03lbackup20041PLANREVU\Memo 08lsupsp0805.doc QV STEWART RIPRAP OUTLET PROTECTION WORKSHEET Project White Deer Park Date 24-Apr-08 Project No. C7005 Designer ACP Outlet ID CV-1 Outlet flowrate 3.5 cfs Pipe diameter 12 inches Outlet pipe slope 1.31 percent Full flow velocity 4.5 ft/sec 25 20 u 15 U 10 5 sec 0 0 1 2 3 Figure 8.06.b.1 4 5 6 7 8 Pipe diameter (ft) 9 10 1 Zone from graph above = 1 Outlet pipe diameter 12 in. Length = 4.0 ft. Outlet flowrate 3.5 cfs Width = 3.0 ft. Outlet velocity 4.5 ft/see Stone diameter = 3 in. Material = Class A Thickness = 9 in. Zone Material Diameter Thickness Length Width 1 Class A 3 9 4 x D(o) 3 x D(o) 2 Class B 6 22 6 x D(o) 3 x D(o) 3 Class I 13 22 8 x D(o) 3 x D(o) 4 Class I 13 22 8 x D(o) 3 x D(o) 5 Class 11 23 27 10 x D(o) 3 x D(o) 6 Class II 23 27 10 x D(o) 3 x D(o) 7 Special stud required ices STEWART RIPRAP OUTLET PROTECTION WORKSHEET Project White Deer Park Date 24-Apr-08 Project No. C7005 Designer ACP Outlet ID CV-2 Outlet flowrate 8.1 cfs Pipe diameter 18 inches Outlet pipe slope 1.56 percent Full flow velocity 4.6 ft/sec 25 20 u 15 w Lam' 10 > 5 0 0 1 2 3 4 5 6 7 8 9 10 Pipe diameter (ft) Zone from graph above = 1 Outlet pipe diameter 18 in. Length = 6.0 ft. Outlet flowrate 8.1 cfs Width = 4.5 ft. Outlet velocity 4.6 ft/see Stone diameter = 3 in. Material = Class A Thickness = 9 in. Zone Material Diameter Thickness Length Width 1 Class A 3 9 4 x D(o) 3 x D(o) 2 Class B 6 22 6 x D(o) 3 x D(o) 3 Class I 13 22 8 x D(o) 3 x D(o) 4 Class I 13 22 8 x D(o) 3 x D(o) 5 Class 1 1 23 27 10 x D(o) 3 x D(o) 6 Class H 23 27 10 x D(o) 3 x D(o) 7 Special stud required Figure 8.06.b.1 STE WART RIPRAP OUTLET PROTECTION WORKSHEET Project White Deer Park Date 24-Apr-08 Project No. C7005 Designer ACP Outlet ID CV-3 Outlet flowrate 4 cfs Pipe diameter 15 inches Outlet pipe slope 7.5 percent Full flow velocity 33 ft/sec Fi¢ure 8.06.b.1 25 20 U 15 W v 10 5 0 1 2 3 4 5 6 7 Pipe diameter (ft) 8 9 10 1 Zone from graph above = 1 Outlet pipe diameter 15 in. Length = 5.0 ft. Outlet flowrate 4.0 cfs Width = 3.8 ft. Outlet velocity 3.3 ft /see Stone diameter = 3 in. Material=- Class A Thickness = 9 in. Z Diameter Thickness Length Width 3 9 4 x D(o) 3 x D(o) V 6 22 6 x D(o) 3 x D(o) a 13 22 8 x D(o) 3 x D(o) 13 22 8 x D(o) 3 x D(o) 5 - Class II 23 27 10 x D(o) 3 x D(o) 6 Class II 23 27 10 x D(o) 3 x D(o) 7 Special study reauired STEWART RIPRAP OUTLET PROTECTION WORKSHEET Project White Deer Park Date 24-Apr-08 Project No. C7005 Designer ACP Outlet ID CV-4 Outlet flowrate 18.6 cfs Pipe diameter 24 inches Outlet pipe slope 2.94 percent Full flow velocity 5.9 ft/sec u d w v 'u 0 u Figure 8.06.b.1 0 1 2 3 4 5 6 7 g Pipe diameter (ft) Zone from graph above = 2 Outlet pipe diameter 24 in. Length = 12.0 ft. Outlet flowrate 18.6 cfs Width = 6.0 ft. Outlet velocity 5.9 ft/see Stone diameter = 6 in. Material = Class B Thickness = 22 in. Zone Material Diameter Thickness Length Width 1 Class A 3- 9 4 x D(o) 3 x D(o) 2 Class B 6 22 6 x D(o) 3 x D(o) 3 C1assl 13 22 8 x D(o) 3 x D(o) 4 Class I 13 22 8 x D(o) 3 x D(o) 5 Class R 23 27 10 x D(o) 3 x D(o) 6 Class II 23 27 10 x D(o) 3 x D(o) 7 Special study required STE WART RIPRAP OUTLET PROTECTION WORKSHEET Project White Deer Park Date 24-Apr-08 Project No. C7005 Designer ACP Outlet ID CV--5 Outlet flowrate 0.95 cfs Pipe diameter 15 inches Outlet pipe slope 7.14 percent Full flow velocity 0.8 ft/sec Fieure 8.06.b.1 25 'Zone .? 20 15 -t- ° 10 5 - Zang.3.. Zw?e.3_ 0 ne cut; 0 1 2 3 4 5 6 7 8 9 10 Pipe diameter (ft) Zone from graph above = 1 Outlet pipe diameter 15 in. Length = 5.0 ft. Outlet flowrate 1.0 cfs Width = 3.8 ft. Outlet velocity ' 0.8 ft/see Stone diameter = 3 in. aterial = Material= Class A Thickness = 9 in. Zone Material Diameter Thickness Length Width 1 Class A 3 9 4 x D(o) 3 x D(o) 2 Class B 6 22 6 x D(o) 3 x D(o) 3 Class I 13 22 8 x D(o) 3 x D(o) 4 Class 1 13 22 8 x D(o) 3 x D(o) 5 Class II 23 27 10 x D(o) 3 x D(o) 6 Class 11 23 27 10 x D(o) 3 x D(o) 7 Special stud required STE WART RIPRAP OUTLET PROTECTION WORKSHEET Project White Deer Park Date 24-Apr-08 Project No. C7005 Designer - ACP Outlet ID CV-6 Outlet flowrate 5 cfs Pipe diameter 15 inches Outlet pipe slope 10.7 percent Full flow velocity 4.1 ft /sec 25 Fieure 8.06.b.1 Zune l:7.. 20 u - zone yy? 15 O 10 o n T > .. ........ .:.......... 2 4ne-4 5 ; _.. on ... 0 0 1 2 3 4 5 6 Pipe diameter (ft) 7 8 9 10 Zone from graph above = 1 Outlet pipe diameter 15 in. Length ,= 5.0 #t. Outlet flowrate 5.0 cfs Width = 3.811. Outlet velocity 4.1 ft/sec Stone diameter = 3 in. Material = Class A Thickness = 9 in. Zone Material Diameter Thickness Length Width 1 Class A 3 9 4 x D(o) 3 x D(o) 2 Class B 6 22 6 x D(o) 3 x D(o) 3 Class I 13 22 ` 8 x D(o) 3 x D(o) 4 Class I 13 22 8 x D(o) 3 x D(o) 5 Class H 23 27 10 x D(o) 3 x D(o) 6 Class 11 23 27 10 x D(o) 3 x D(o) 7 Special stud required STE WART RIPRAP OUTLET PROTECTION WORKSHEET Project White Deer Park Date 24-Apr-08 - Project No. C7005 Designer - ACP Outlet ID CV-7 Outlet flowrate 3.2 cfs Pipe diameter 15 inches Outlet pipe slope 2.22 percent Full flow velocity 2.6 ft/sec 25 Fieure 8.06.b.1 iZone .7.. 20 - gene u N 15 . :. ...,.. V ° 10 ..., Q d - - ---- .:._.. 7. ----------- - Qne 4 5 dne:f_ ec 0 0 1 2 3 ---r- - 7. .'A . ne.:... 4 5 6 7 8 9 10 Pipe diameter (ft) Zone from graph above = 1 Outlet pipe diameter 15 in. Length = 5.0 ft. Outlet flowrate 3.2 cfs Width = 3.8 ft. Outlet velocity 2.6 ft/see Stone diameter = 3 in. Material = Class A Thickness = 9 in. Zone Material Diameter Thickness Length Width 1 Class A 3 9 4 x D(o) 3 x D(o) 2 Class B 6 22 6 x D(o) 3 x D(o) 3 Class 1 13 22 8 x D(o) 3 x D(o) 4 Class I 13 22 8 x D(o) 3 x D(o) 5 Class H 23 27 10 x D(o) 3 x D(o) 6 Class II 23 27 10 x D(o) 3 x D(o) 7 Special stud required STE WART RIPRAP OUTLET PROTECTION WORKSHEET Project White Deer Park Date 24-Apr-08 Project No. C7005 Designer ACP Outlet ID CV-8 Outlet flowrate 28 cfs Pipe diameter 30 inches Outlet pipe slope 5.56 percent Full flow velocity 5 7 ft/c Pe Fieure 8.06.b.1 25 20 u 15 w jr 'u 10 5 0 0 1 2 3 4 5 6 7 8 9 10 Pipe diameter (ft) Zone from graph above = 2 Outlet pipe diameter 30 in. Length = 15.0 ft. Outlet flowrate 28.0 cfs Width = 7.5 ft. Outlet velocity 5.7 ft/sec Stone diameter = 6 in. Material = Class B Thickness = 22 in. Zone Material Diameter Thickness Length Width 1 Class A 3 9 4 x D(o) 3 x D(o) 2 Class B 6 22 6 x D(o) 3 x D(o) 3 Class I 13 22 8 x D(o) 3 x D(o) 4 Class I 13 22 8 x D(o) 3 x D(o) 5 Class II 23 27 10 x D(o) 3 x D(o) 6 Class H 23 27 10 x D(o) 3 x D(o) 7 Special stud required ` .H STE WART RIPRAP OUTLET PROTECTION WORKSHEET Project White Deer Park Date 24-Apr-08 Project No. C7005 Designer ACP Outlet ID CV-9 Outlet flowrate 0.52 cfs Pipe diameter 15 inches Outlet pipe slope 4.17 percent Full flow velocity 0.4 ft/sec , 25 20 v 15 w i'1 u 10 5 0 1 2 3 4 5 6 7 8 9 10 Pipe diameter (ft) Zone from graph above = 1 Outlet pipe diameter, 15 in. Length = 5.0 ft. Outlet flowrate 0.5 cfs Width = 3.8 ft. Outlet velocity 0.4 fUsec Stone diameter = 3 in. Material=- Class A Thickness = 9 in. Cnlrnlati- 1--A Zone Material Diameter Thickness Length Width 1 Class A 3 4 x D(o) 3 x D(o) 2 Class B 6 6 x D(o) 3 x D(o) 3 Class I 13 T 8 x D(o) 3 x D(o) 4 Class I 13 8 x D(o) 3 x D(o) 5 Class 11 23 10 x D(o) 3 x D(o) 6 Class II 23 27 10 x D(o) 3 x D(o) 7 .. ATV Special study required ? Fieure 8.06.b.1 ..;;, fu STEWART RIPRAP OUTLET PROTECTION WORKSHEET Project White Deer Park Date` 24-Apr-08 Project No. C7005 Designer ACP Outlet ID CV-10 Outlet flowrate 1.2 cfs Pipe diameter 15 inches Outlet pipe slope 0 percent Full flow velocitv 1 () ft/qP?. 25 20 u 15 w V 10 5 Fi¢ure 8.06.b.1 0 1 2 3 4 5 6 7 g 9 10 Pipe diameter (ft) Zone from graph above = 1 Outlet pipe diameter 15 in. Length = 5.0 ft. Outlet flowrate 1.2 cfs Width = 3.8 ft. Outlet velocity 1.0 fl/sec . Stone diameter= 3 in. Material = Class A Thickness = 9 in: Zone Material Diameter Thickness Length Width 1 Class A 3 9 4 x D(o) 3 x D(o) 2 Class B - 6 22 6 x D(o) - 3 x D(o) 3 Class I 13 22 8x D(o) 3 x D(o) 4 Class I 13 22 8 x D(o) 3 x D(o) 5 Class 11 23 27 10 x D(o) 3 x D(o) 6 Class II 23 27 10 x D(o) 3 x D(o) 7 Special stud required STE WART _ . RIPRAP OUTLET PROTECTION WORKSHEET Project White Deer Park Date 24-Apr-08 Project No. C7005 Designer ACP Outlet ID CV-11 Outlet flowrate 0.6 cfs Pipe diameter 15 inches Outlet pipe slope 1 percent Full flow velocity 0.5 ft/sec 25 20 v 15 v Z 10- 5 0 0 1 2 3 .4 5 6 7 8 Pipe diameter (ft) 9 10 Zone from graph above = 1 Outlet pipe diameter 15 in. Length = 5.0 ft. Outlet flowrate 0.6 cfs Width = 3.8 ft. Outlet velocity 0.5 fusee Stone diameter = 3 in. Material=- Class A Thickness = 9 in. Zone Material Diameter Thickness Length Width 1 Class A 3 9 4 x D(o) 3 x D(o) 2 Class B 6 22 6 x D(o) 3 x D(o) 3 Class I 13 22 8 x D(o) 3 x D(o) 4 Class I 13 22 8 x D(o) 3 x D(o) 5 Class II 23 27 10 x D(o) 3 x D(o) 6 Class II 23 27 10 x D(o) 3 x D(o) 7 Special stud required Fl¢ure 8.06.b.1 IJULIUL IL lJ V-I/ Outlet flowrate 2.9 cfs Pipe diameter 15 inches Outlet pipe slope 0 percent Full flow velocity. 2.4 ft/sec Fieure 8.06.b.1 25 ZoneG.4.. 20 -?onefi- V j 15 ....:.:...,.:.... Z .°. 10 a d .. -7Ane.A.: 5 + ..7rane ?_ - ?..-- Zobe-3. 0 ° l 2- 3 4 5 6 7 8 9 10 Pipe diameter (ft) Zone from graph above = 1 Outlet pipe diameter 15 in. Length = 5.0 ft. Outlet flowrate 2.9 cfs Width = 3.8 fl. Outlet velocity 2.4 ft/sec Stone diameter = 3 in. Material = Class A Thickness = 9 in. Zone Material Diameter Thickness Length Width 1 Class A 3 9 4 x D(o) 3 x D(o) 2 Class B 6 22 6 x D(o) • 3 x D(o) 3 Class I 13 22 8 x D(o) 3 x D(o) 4 Class I 13 22 8 x D(o) 3 x D(o) 5 Class H 23 27 10 x D(o) 3 x D(o) 6 Class H 23 27 10 x D(o) 3 x D(o) 7 Special stud required +J STE WART RIPRAP OUTLET PROTECTION WORKSHEET Project White Deer Park ` Date 24-Apr-08 Project No. C7005 Designer ACP Outlet ID FES-3 Outlet flowrate 7.79 cfs Pipe diameter 18 inches Outlet pipe slope 0.5 percent: Full flow velocity 4.4 ft/sec 25 Fieure 8.06.b.1 Znne t7? 20 u 15 ° 10 ° > ,.. _ Zo ne.A.. 5 .Z.Q ne-f- .Zn e.3. 0 0 1 ne ? 2 -3 4 5 6 7 8 9 10 Pipe diameter (ft) Zone from graph above = 1 Outlet pipe diameter 18 in. Outlet flowrate 7.8 cfs Outlet velocity 4.4 ft/sec Material= Class A Length = 6.0 ft. Width = 4.5 ft. Stone diameter= 3 in. Thickness = 9 in. Zone Material Diameter Thickness Length Width 1 Class A 3 9 4 x D(o) 3 x D(o) 2 Class B 6 - 22 6 x D(o) 3 x D(o) 3 Class I 13 22 8 x D(o) 3 x D(o) 4 Class I 13 22 8 x D(o) 3 x D(o) 5 Class If 23 27 10 x D(o) 3 x D(o) 6 Class H 23 27 10 x D(o) 3 x D(o) 7 Special stud required Outlet flowrate 5.73 cfs Pipe diameter 18 inches Outlet pipe slope 0.8 percent Full flow velocity 3.2 ft/sec Fieure 8.06.b.1 LJ 20 u 15 w_ jr 'u 10 5 0 1 2 3 4 5 6 7 8 9 10 Pipe diameter (ft) Zone from graph above = 1 Outlet pipe diameter 18 in. Length = 6.0 ft. Outlet flowrate 5.7 cfs Width = 4.5 ft. Outlet velocity 3.2 ft/sec Stone diameter= 3 in. Material = Class A Thickness = 9 in. Zone Material Diameter Thickness Length Width 1 Class A 3 9 4 x D(o) 3 x D(o) 2 Class B 6 22 6 x D(o) 3 x D(o) 3 Class I 13 22 8 x D(o) 3 x D(o) 4 Class I 13 22 8 x D(o) 3 x D(o) 5 Class II 23 27 10 x D(o) 3 x D(o) 6 Class II 23 27 10 x D(o) 3 x D(o) 7 Special study required Print Preview Calculation Detailed Summary Element Details ID - 13 Notes Label Base Calculation Options Hydraulic Summary Flow Profile Method Backwater Analysis Average Velocity Actual Uniform Flow Method Velocity Number of Flow Profile Minimum Structure Steps 5 Headloss 0.00 ft Hydraulic Grade Minimum Time of Convergence Test 0.001 ft Concentration 5.000 min Inlets Neglect Side Flow? False Active Components for Combination Inlets In Grate and Curb Sag Neglect Gutter Cross Active Components for Slope For Side Flow? True Combination Inlets on Grate and Curb Grade HEC-22 Elevations Considered Depressed Equal Within 0.50 ft Unsubmerged 1.000 Consider Non-Piped False Half Bench Submerged 0.950 Plunging Flow Flat Submerged 1.000 Half Bench Unsubmerged 0.150 Flat Unsubmerged 1.000 Full Bench Submerged 0.750 Depressed Submerged 1.000 Full Bench Unsubmerged 0.070 AASHTO Expansion, Ke 0.350 Shaping Adjustment, Cs 0.500 Contraction, Kc 0.250 Non-Piped Flow Adjustment, Cn 1.300 Bend Angle VS. Bend LOSS Curve Bend Anqle Bend Loss Coefficient, Kb (aegrees 0.00 0.000 15.00 0.190 30.00 0.350 45.00 0.470 60.00 0.560 75.00 0.640 90.00 0.700 Catchment Summary Label Area Time of Concentration Rational C Catchment CA raf rP0 (min) CB-1 CATCH 0.135 5.000 0.950 0.129 C13-2 CATCH 0.175 5.000 0.950 0.166 CB-3 CATCH 0.317 5.000 0.950 0.301 Catchment Intensity Catchment Rational (in/hr) Flow (ft3/s) 7.220 0.94 7.220 1.21 7.220 2.19 Conduit Summary Label Conduit Conduit Shape Branch ID Subnetwork Flow Descriotia) aa...rf?ff -a,,-? CO-1 Circular Pipe - 15.0 in Circular Pipe 3 FES-2 1.01 CO-2 Circular Pipe - 15.0 in Circular Pipe 3 FES-2 2.50 CO-3 Circular Pipe - 15.0 in Circular Pipe 4 FES-1 0.74 CO-4 Circular Pipe - 15.0 in Circular Pipe 1 FES-3 3.22 CO-5 Circular Pipe - 18.0 in Circular Pipe 1 FES-3 4.57 CO-6 Circular Pipe - 15.0 in Circular Pipe 2 FES-4 2,62 CO-7 Circular, Pipe - 12.0 in Circular Pipe 2 FES-4 Velocity Hydraulic Grade Hydraulic Grade Depth (In) Depth (Out) (Average) Line (In) Line (out) (ft) (ft} (ft/ss rftl` rt+? 3.11 Label Element Type Subnetwork Outfall Flow (T otal Surface) Flow (Total Out) (ft3/s) (ft3/s) White Deer roadway stc Bentley Systems, Inc. Haestad Methods Solution Bentley StormCAD V8 XM Edition . Center [08.09.081.00] 27 Siemon Company Drive Suite 200 W 412812008 Watertown, CT 06795 USA +1-203-755-1666 Page 2 of 3 3.37 289.20 287.82 0.40 0.52 4.33 287.73 287.10 0.63 0.60 3.55 292.34 291.98 0.34 0.28 6.56 268.14 265.40 0.72 0.98 4.72 265.24 264.56 0.82 0.81 .78 3 273.14 273.03 0.72 0.93 4.58 272.91 272.06 0.81 0.76 Node Summary CB-1 Catch Basin FES-1 0.94 0.74 CB-2 Catch Basin FES-2 1.21 1.01 CB-3 Catch Basin FES-2 2.19 2.50 RISER D Catch Basin FES-3 3.22 3.22 RISER C Catch Basin FES-3 4.57 4.57 RISER A Catch Basin FES-4 2.62 2.62 RISER B Catch Basin FES-4 3.11 3.11 Elevation (Ground) Elevation (Invert)' Energy Grade Line (In) Energy Grade Line (ft1 (ft) (ft) (Out) /R\ 295.00 292.00 292.48 292.46 291.50 288.80 289.36 289.34 289.70 287.10 288.07 287.98 272.42 267.42 268.49 268.44 269.42 264.42 265.73 265.57 277.42 272.42 273.37 273.34 277.42 272.10 273.36 273.23 Label Inlet Type Inlet Summary Inlet Type (Inlet) Inlet Flow (Total Intercepted) iw?i CB-1 Catalog Inlet Combination NCDOT TYPE F 0.74 CB-2 Catalog Inlet Combination NCDOT TYPE F 1.01 CB-3 Catalog Inlet Combination NCDOT TYPE F 1.57 RISER D Percent Capture (N/A) (N/A) 0.00 RISER C Percent Capture (N/A) (N/A) 0.00 RISER A Percent Capture (N/A) (N/A) 0.00 RISER B Percent Capture (N/A) (N/A) 0.00 Flow (Total Bypassed) Bypass Target Capture Efficiency Gutter Depth Gutter Spread (ft?,/s) (Calculated) (in) (ft) roil 0.19 CB-2 79.4 1.4 5.7 0.39 CB-3 72.0 1.6 6.7 1.01 <None> 60.9 2.0 8.4 0.00 <None> 100.0 0.0 0.0 0.00 <None> 100.0 0.0 0.0 0.00 <None> 100.0 OA 0.0 0.00 <None> 100.0 0.0 0.0 i v 1 it0 [ 3 i j i £ t j S } I 3 j ? 1 8 O 3 7 co LU i(D N ? N 1 i E 8 O i { t 1 j i i t tJ Li N N v K C4 N i m 3 p M M co h - t : W ELL IQ m N 1 . N j O f iln 3. I pt i j i? W O N (u) u01;ena13 3 t f 1 4 u a N E C N ry' t r N tV :. 3 jU L W y v y F m O ? ? 1 f i i 3 i l] i a Lu # O i N1 } O NON N N ? N N O- i C i i e hlt i; C6 l E s .01 cli E ( i i i N 3 ? j E S i { i i e O t0 V 1 i f O5 I` ; ? U . N N { i N i i l o ' N E ?N i 21 I 1 } ~ } j E E t } % 9 f Q ?j E 3 E } E I 1 f O 3 f 3 ? i S E ? ? i i f f ; i A 3 I ? E V i + ? E # E . ' } i f ? U . U E i . O l ? P n ? ? ? iV 7 O ' J?4 E ,_,. .3 f ; j E i 3. } i m i 1 i E E i 1 I I ?} ..$ i I I 1 1 f ! E r ` t 3 3 f E ? f i V } t L E ? 3 ] N i i € .. ui } € t ii . r>a ? 3 N S " O ?U i- i qf . O ? ^ ' W •f N p v N co Qp V N m (O p 7 N Op OD tp N r OD t0 V p '? O ? v) N O w N $N N N M ? O N wT O O1 m t0 W c0 n r n r W t0 <O <O N NO N N N N N N m OD W N tD OD lD N N (O m N N N N N N N N N N N N r N ry (11) u0i;ena13 Appendix 7 Gutter spread Calculations Calculation Detailed Summary Element Details ID 13 Notes Label Base Calculation Options Hydraulic Summary Flow Profile Method Backwater Analysis Average Velocity Actual Uniform Flow Method Velocity Number of Flow Profile Minimum Structure Steps 5 Headloss 0.00 ft Hydraulic Grade Minimum Time of Convergence Test 0.001 ft Concentration 5.000 min Inlets Neglect Side Flow? False Active Components for Combination Inlets In Grate and Curb Sag Neglect Gutter Cross Active Components for Slope For Side Flow? True Combination Inlets on Grate and Curb Grade HEC-22 Elevations Considered Depressed Equal Within 0.50 ft Unsubmerged 1.000 Consider Non-Piped False Half Bench Submerged 0.950 Plunging Flow Flat Submerged 1.000 Half Bench Unsubmerged 0.150 Flat Unsubmerged 1.000 Full Bench Submerged 0.750 Depressed Submerged 1.000 Full Bench Unsubmerged 0.070 AASHTO Expansion, Ke 0.350 Shaping Adjustment, Cs 0.500 Contraction, Kc 0.250 Non-Piped Flow Adjustment, Cn 1.300 Bend Angle vs. Bend Loss Curve Bend Angle Bend Loss Coefficient, Kb Bentley Systems, Inc. Haestad Methods Solution Bentley StormCAD V8 XM Edition White Deer roadwaystc Center [08.09.081.00] 27 Siemon Company Drive Suite 200 W 4/2212008 Watertown, CT 06795 USA +1-203-755-1666 Page 1 of 3 Governing Upstream Pipe with Maximum Pipe Selection Method Qy Catchment Summary Label Area Time of Rational C Catchment CA Catchment (acres) Concentration (acres) Intensity min) (in/hr) CB-1 CATCH 0.135 5.000 0.950 0.129 5.760 CB-2 CATCH 0.175 5.000 0.950 0.166 5.760 CB-3 CATCH 0.317 5.000 0.950 0.301 5.760 Catchment Rational Flow (ft3/s} 0.75 0.97 1.75 Conduit Summary Label Conduit Descrtotion C(x)duiL Shaoe Branch f n 4i 1hnahunr ( tli iifaii CO-1 Circular Pipe - 15.0 in Circular Pipe 1 OF-1 CO-2 Circular Pipe - 15.0 in Circular Pipe 1 OF-1 CO-3 Circular Pipe - 15.0 in Circular Pipe 2 FES-1 Flow Velocity (Average) Hydraulic Grade Line Hydraulic Grade Line Depth (In) (ft3/S) (ft/s) (In) (Out) (ft) (ft) (R 1 0.84 3.19 289.16 287.75 0.36 2.06 4.12 287.67 287.03 0.57 0.62 3.37 292.31 291.96 0.31 Depth (Out} (ft) 0.45 0.53 0.26 Node Summary Label Element Type Subnetwork Flow (Total Flow!,Total Out) Elevation Outfall Surface) (ft3/s) (Ground) (ft3/C) tft1 Elevation Energy Grade Energy Grade (Invert) Line (In) Line (Out) (ft) (ft) (ft} 292.00 292.43 292.42 Bentley Systems, Inc. Haestad Methods Solution Bentley StormCAD V8 XM Edition White Deer roadway.stc Center [08.09.081.00] 27 Siemon Company Drive Suite 200 W Page 2 of 3 4/22/2008 Watertown, CT 06795 USA +1-203-755-1666 CB-1 Catch Basin FES-1 0.75 0.62 295.00 CB-2 Catch Basin OF-1 0.97 0.84 291.50 CB-3 Catch Basin OF-1 1.75 2.06 289.70 Calculation Detailed Summary Node Summary Elevation Energy Grade Energy Grade (Invert) Line (In) Line (Out) 8.80 8 1 289.31 1 289.29 8 0 287.97 287.89 Inlet Summary Label Inlet Type Inlet Type Inlet Flow (Total Flow (Total (Inlet) Intercepted) Bypassed) (tt3/s) (ft3l/s) CB-1 Catalog Inlet Combination NCDOT TYPE F 0.62 0.12 C13-2 Catalog Inlet Combination NCDOT TYPE F 0.84 0.26 CB-3 Catalog Inlet Combination NCDOT TYPEF 1.31 0.69 Bypass Target Capture Gutter Depth Gutter Spread Efficiency (in) (ft) (Calculated) f °?o) C13-2 83.3 1.3 5.2 CB-3 76.6 1.5 6.1 <None> 65.5 1.8 7.6