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Home My WebLink About20111120 Ver 1_401 Application_20111211WITHERS & RAVENEL ENGINEERS I PLANNERS I SURVEYORS 111 MacKenan Drive CARY, NORTH CAROLINA, 27511 (919) 469 3340 FAX (919) 467 6008 TO NC DENR 1601 Mail Service Center Raleigh NC 27699 1601 WE ARE SENDING YOU ❑ Shop Drawings ❑ Copy of Letter ❑ Attached via ❑ Prints ❑ Change order 20 1 1 1 12 0 LETTER OF TRANSMITTAL DATE 12 22 11 —JOB NO 02110380 ATTENTION Ian McMillan PHONE # 919 807 6364 RE Eagle Rock Concrete Buffer Authorization 1 1222 11 1 ❑ Plans ❑ Diskette _ the following items ❑ Samples ❑ Specifications El COPIES DATE NO DESCRIPTION 1 1222 11 1 SWMP Report 1 1222 11 2 PCN Form 1 1222 11 3 fWetland Supplement 1 1222 11 4 no JD) Plan Sheets DENR WAitnuu" THESE ARE TRANSMITTED as checked below %NETLANDa AND SIORMWAIERBRANC ❑ For approval ❑ Approved as submitted ❑ Resubmit copies for approval ® For your use ❑ Approved as noted ❑ Submit copies for distribution ❑ As requested ❑ Returned for corrections ❑ Return corrected prints ❑ For review and comment ❑ ❑ FOR BIDS DUE 20 ❑ PRINTS RETURNED AFTER LOAN TO US REMARKS Ian — we are seeking buffer approval for the bypass channel coming out of the constructed Wetland The second discharge point is for the industrial outfall to be permitted under NCG 14 Please feel free to call with any questions 919 469 3340 COPY TO W &R FILE SIGNED Hunter Freeman if enclosures are not as noted kindlynotify us at once 0' A��TF9OG > 20 1 1 1 12 0 Office Use Only Corps action ID no DWQ project no Form Version 1 3 Dec 10 2008 Page 1 of 10 PCN Form — Version 1 3 December 10 2008 Version Pre - Construction Notification PC Form A Applicant Information 1 Processing la Type(s) of approval sought from the Corps F El Section 404 Permit El Section 10 Permit 1 b Specify Nationwide Permit (NWP) number or General Permit (GP) number 1c Has the NWP or GP number been verified by the Corps? ❑ Yes ❑ No 1 d Type(s) of approval sought from the DWQ (check all that apply) ❑ 401 Water Quality Certification — Regular ❑ Non -404 Jurisdictional General Permit ❑ 401 Water Quality Certification — Express ® Riparian Buffer Authorization le Is this notification solely for the record because written approval is not required? For the record only for DWQ 401 Certification ❑ Yes ® No For the record only for Corps Permit ❑ Yes ® No if Is payment into a mitigation bank or in lieu fee program proposed for mitigation of impacts? If so attach the acceptance letter from mitigation bank or in lieu fee program ❑ Yes ® No 1g Is the project located in any of NC s twenty coastal counties If yes answer 1 h below ❑ Yes ® No 1h Is the project located within a NC DCM Area of Environmental Concern (AEC)? ❑ Yes ® No 2 Project Information 2a Name of project Eagle Rock Concrete 2b County Wake 2c Nearest municipality / town Garner 2d Subdivision name Greenfield 2e NCDOT only TIP or state project no VVEWD UMN WATER -) ANDSTORMWA EI RSRANCK 3 Owner Information 3a Name(s) on Recorded Deed Greenfield 40 Assoc LLC 3b Deed Book and Page No 12054 pg 0742 3c Responsible Party (for LLC if applicable) 3d Street address 901 Old Knight Road 3e City state zip Knightdale NC 27545 3f Telephone no 3g Fax no 3h Email address Page 1 of 10 PCN Form — Version 1 3 December 10 2008 Version 4 Applicant Information (if different from owner) 4a Applicant is ❑ Agent ® Other specify Developer 4b Name Adam Loftin 4c Business name (if applicable) Eagle Rock 4d Street address 8310 Bandford Way 4e City state zip Raleigh NC 27614 4f Telephone no 919 819 1100 4g Fax no 4h Email address ajloftm @gmail com 5 Agent/Consultant Information (if applicable) 5a Name Hunter Freeman 5b Business name (if applicable) Withers & ravenel 5c Street address 111 MacKenan Drive 5d City state zip Cary NC 27511 5e Telephone no 919 -469 3340 5f Fax no 919 467 6008 5g Email address hfreeman @withersravenel corn Page 2 of 10 PCN Form —Version 1 3 December 10 2008 Version B Project Information and Prior Project History 1 Property Identification 1a Property identification no (tax PIN or parcel ID) 1730125497 lb Site coordinates (in decimal degrees) Latitude 78 56 Longitude 3568 (DD DDDDDD) ( DD DDDDDD) lc Property size 5 77 acres 2 Surface Waters 2a Name of nearest body of water (stream river etc ) to proposed project White Oak Creek 2b Water Quality Classification of nearest receiving water C NSW 2c River basin Neuse 3 Project Description 3a Describe the existing conditions on the site and the general land use in the vicinity of the project at the time of this application Undeveloped Parcel within an industrial subdivision 3b List the total estimated acreage of all existing wetlands on the property Oil 3c List the total estimated linear feet of all existing streams (intermittent and perennial) on the property 875 3d Explain the purpose of the proposed project Ready Mix Concrete Plant 3e Describe the overall project in detail including the type of equipment to be used The project includes site development of the proposed concrete plant general site construction equipment will be used 4 Jurisdictional Determinations 4a Have jurisdictional wetland or stream determinations by the Corps or State been requested or obtained for this property ! project (including all prior phases) in the past Comments ® Yes El No El Unknown 41b If the Corps made the jurisdictional determination what type of determination was made? ❑ Preliminary ® Final 4c If yes who delineated the jurisdictional areas? Name (if known) Agency /Consultant Company Other 4d If yes list the dates of the Corps jurisdictional determinations or State determinations and attach documentation 5 Project History 5a Have permits or certifications been requested or obtained for this project (including all prior phases) in the past? ❑ Yes ® No ❑ Unknown 5b If yes explain in detail according to help file instructions 6 Future Project Plans 6a Is this a phased project? ❑ Yes ® No 6b If yes explain Page 3 of 10 PCN Form — Version 1 3 December 10 2008 Version C Proposed Impacts Inventory 1 Impacts Summary la Which sections were completed below for your project (check all that apply) ❑ Wetlands ❑ Streams tributaries ❑ Buffers ❑ Open Waters ❑ Pond Construction 2 Wetland Impacts If there are wetland impacts proposed on the site then complete this question for each wetland area impacted 2a 2b 2c 2d 2e 2f Wetland impact Type of Jurisdiction number — Type of impact Type of wetland Forested (Corps 404 10 Area of impact Permanent (P) or (if known) DWQ — non -404 other) (acres) Temporary T W1 ❑ P ❑ T ❑ Yes ❑ Corps ❑ No ❑ DWQ W2 ❑ P ❑ T ❑ Yes ❑ Corps ❑ No ❑ DWQ W3 ❑ P ❑ T ❑ Yes ❑ Corps ❑ No ❑ DWQ W4 ❑ P ❑ T ❑ Yes ❑ Corps ❑ No ❑ DWQ W5 ❑ P ❑ T ❑ Yes ❑ Corps El No El DWQ W6 ❑ P ❑ T ❑ Yes ❑ Corps ❑ No ❑ DWQ 2g Total wetland impacts 2h Comments 3 Stream Impacts If there are perennial or intermittent stream impacts (including temporary impacts) proposed on the site then complete this question for all stream sites impacted 3a 3b 3c 3d 3e 3f 3g Stream impact Type of impact Stream name Perennial Type of Jurisdiction Average Impact number (PER) or (Corps 404 10 stream length Permanent (P) or intermittent DWQ — non 404 width (linear Temporary (T) (INT)? other) (feet) feet) S1 ❑ P ❑ T ❑ PER ❑ Corps ❑ INT ❑ DWQ S2 ❑ P ❑ T ❑ PER ❑ Corps ❑ INT ❑ DWQ S3 ❑ P ❑ T ❑ PER ❑ Corps ❑ INT ❑ DWQ S4 ❑ P ❑ T ❑ PER ❑ Corps ❑ INT ❑ DWQ SS ❑ P ❑ T ❑ PER ❑ Corps ❑ INT ❑ DWQ S6 ❑ P ❑ T ❑ PER ❑ Corps ❑ INT ❑ DWQ 31h Total stream and tributary impacts X Comments Page 4 of 10 PCN Form — Version 1 3 December 10 2008 Version 4 Open Water Impacts If there are proposed impacts to lakes ponds estuaries tributaries sounds the Atlantic Ocean or any other open water of the U S then individually list all open water impacts below 4a 4b 4c 4d 4e Open water Name of waterbody impact number — (if applicable) Type of impact Waterbody type Area of impact (acres) Permanent (P) or Temporary T 01 ❑P ❑T 02 ❑P ❑T 03 ❑P ❑T 04 ❑P ❑T 4f Total open water impacts 4g Comments 5 Pond or Lake Construction If pond or lake construction proposed the complete the chart below 5a 5b 5c 5d 5e Wetland Impacts (acres) Stream Impacts (feet) Upland Pond ID Proposed use or purpose (acres) number of pond Flooded Filled Excavated Flooded Filled Excavated Flooded P1 P2 5f Total 5g Comments 5h Is a dam high hazard permit required ❑ Yes ❑ No If yes permit ID no 51 Expected pond surface area (acres) 51 Size of pond watershed (acres) 5k Method of construction 6 Buffer Impacts (for DWQ) If project will impact a protected riparian buffer then complete the chart below If yes then individually list all buffer impacts below If any impacts require mitigation then you MUST fill out Section D of this form 6a ® Neuse El Tar Pamlico El Other Project is in which protected basin? ❑ Catawba ❑ Randleman 61b 6c 6d 6e 6f 6g Buffer impact number — Reason Buffer Zone 1 impact Zone 2 impact Permanent (P) or for Stream name mitigation (square feet) (square feet) Temporary T impact required? 61 ®P ❑ T Channel Tnb to White Oak ® Yes 164 B2 ❑ P ❑ T ❑ Yes ❑ No B3 ❑ P ❑ T ❑ Yes ❑ No 6h Total buffer impacts Gi Comments Page 5 of 10 PCN Form — Version 1 3 December 10 2008 Version D Impact Justification and Mitigation 1 Avoidance and Minimization 1a Specifically describe measures taken to avoid or minimize the proposed impacts in designing project Impact is require per standards for constructed wetland BMP 1 b Specifically describe measures taken to avoid or minimize the proposed impacts through construction techniques Channel size was minimized 2 Compensatory Mitigation for Impacts to Waters of the U S or Waters of the State 2a Does the project require Compensatory Mitigation for impacts to Waters of the U S or Waters of the State? ❑ Yes [-I No 2b If yes mitigation is required by (check all that apply) ❑ DWQ ❑ Corps 2c If yes which mitigation option will be used for this project? ❑ Mitigation bank E] Payment to in lieu fee program ❑ Permittee Responsible Mitigation 3 Complete if Using a Mitigation Bank 3a Name of Mitigation Bank 3b Credits Purchased (attach receipt and letter) Type Quantity 3c Comments 4 Complete if Making a Payment to In lieu Fee Program 4a Approval letter from in lieu fee program is attached ❑ Yes 4b Stream mitigation requested linear feet 4c If using stream mitigation stream temperature ❑ warm ❑ cool ❑cold 4d Buffer mitigation requested (DWQ only) square feet 4e Riparian wetland mitigation requested acres 4f Non riparian wetland mitigation requested acres 4g Coastal (tidal) wetland mitigation requested acres 4h Comments 5 Complete if Using a Permittee Responsible Mitigation Plan 5a If using a permittee responsible mitigation plan provide a description of the proposed mitigation plan Page 6 of 10 PCN Form — Version 1 3 December 10 2008 Version 6 Buffer Mitigation (State Regulated Riparian Buffer Rules) — required by DWQ 6a Will the project result in an impact within a protected riparian buffer that requires buffer mitigation? ❑ Yes ® No 6b If yes then identify the square feet of impact to each zone of the riparian buffer that requires mitigation Calculate the amount of mitigation required Zone 6c Reason for impact 6d Total impact (square feet) Multiplier 6e Required mitigation (square feet) Zone 1 3 (2 for Catawba) Zone 2 1 5 6f Total buffer mitigation required 6g If buffer mitigation is required discuss what type of mitigation is proposed (e g payment to private mitigation bank permittee responsible riparian buffer restoration payment into an approved in lieu fee fund) 6h Comments Page 7of10 PCN Form — Version 1 3 December 10 2008 Version E Stormwater Management and Diffuse Flow Plan (required by DWQ) 1 Diffuse Flow Plan la Does the project include or is it adjacent to protected riparian buffers identified ® Yes ❑ No within one of the NC Riparian Buffer Protection Rules? lb If yes then is a diffuse flow plan included? If no explain why ® Yes ❑ No Comments 1 constructed wetland for stormwater runoff 2 Stormwater Management Plan 2a What is the overall percent imperviousness of this project? 78% 215 Does this project require a Stormwater Management Plan? ® Yes ❑ No 2c If this project DOES NOT require a Stormwater Management Plan explain why 2d If this project DOES require a Stormwater Management Plan then provide a brief narrative description of the plan Runoff from non industrial areas will be treated by a constructed wetland there are no areas of untreated impervious The industrial portion of the site contains one discharge point which will be permuted under NCG14 Approval of stormwater plan from garner is pending bt there are no mayor comments at this time There is no comingling of stormwater and wastewater ® Certified Local Government 2e Who will be responsible for the review of the Stormwater Management Plan? ❑ DWQ Stormwater Program ❑ DWQ 401 Unit 3 Certified Local Government Stormwater Review 3a In which local governments jurisdiction is this project? Garner ® Phase II 3b Which of the following locally implemented stormwater management programs ® NSW ❑ USMP apply (check all that apply) ❑ Water Supply Watershed ❑ Other 3c Has the approved Stormwater Management Plan with proof of approval been ❑ Yes ® No attached? 4 DWQ Stormwater Program Review ❑ Coastal counties ❑ HQW 4a Which of the following state implemented stormwater management programs apply ❑ ORW (check all that apply) ❑ Session Law 2006 246 ❑ Other 4b Has the approved Stormwater Management Plan with proof of approval been attached? ❑ Yes ❑ No 5 DWQ 401 Unit Stormwater Review Sa Does the Stormwater Management Plan meet the appropriate requirements? ® Yes ❑ No 5b Have all of the 401 Unit submittal requirements been met? ® Yes ❑ No Page 8 of 10 PCN Form — Version 1 3 December 10 2008 Version F Supplementary Information 1 Environmental Documentation (DWQ Requirement) la Does the project involve an expenditure of public (federal /state /local) funds or the ❑ Yes ® No use of public (federal /state) land? lb If you answered yes to the above does the project require preparation of an environmental document pursuant to the requirements of the National or State ❑ Yes ❑ No (North Carolina) Environmental Policy Act (NEPA/SEPA)? 1c If you answered yes to the above has the document review been finalized by the State Clearing House? (If so attach a copy of the NEPA or SEPA final approval ❑ Yes ❑ No letter ) Comments 2 Violations (DWQ Requirement) 2a Is the site in violation of DWQ Wetland Rules (15A NCAC 2H 0500) Isolated Wetland Rules (15A NCAC 2H 1300) DWQ Surface Water or Wetland Standards ❑ Yes ® No or Riparian Buffer Rules (15A NCAC 213 0200)? 2b Is this an after the fact permit application? ❑ Yes ® No 2c If you answered yes to one or both of the above questions provide an explanation of the violation(s) 3 Cumulative Impacts (DWQ Requirement) 3a Will this project (based on past and reasonably anticipated future impacts) result in ❑ Yes ® No additional development which could impact nearby downstream water quality? 3b If you answered yes to the above submit a qualitative or quantitative cumulative impact analysis in accordance with the most recent DWQ policy If you answered no provide a short narrative description 4 Sewage Disposal (DWQ Requirement) 4a Clearly detail the ultimate treatment methods and disposition (non discharge or discharge) of wastewater generated from the proposed project or available capacity of the subject facility The wastewater discharge will be permitted under NCG14 Settling bins TSS and pH control are all included in the wastewater treatment design in accordance with the requirements of the permit A monitoring plan is also being developed for the wastewater discharge there is no co mingling of stormwater and wastewater Page 9 of 10 PCN Form — Version 1 3 December 10 2008 Version 5 Endangered Species and Designated Critical Habitat (Corps Requirement) 5a Will this project occur in or near an area with federally protected species or habitat? ❑ Yes ❑ No 5b Have you checked with the USFWS concerning Endangered Species Act impacts? ❑ Yes ❑ No 5c If yes indicate the USFWS Field Office you have contacted ❑ Raleigh ❑ Asheville 5d What data sources did you use to determine whether your site would impact Endangered Species or Designated Critical Habitat? 6 Essential Fish Habitat (Corps Requirement) 6a Will this project occur in or near an area designated as essential fish habitats ❑ Yes ❑ No 6b What data sources did you use to determine whether your site would impact Essential Fish Habitat? 7 Historic or Prehistoric Cultural Resources (Corps Requirement) 7a Will this project occur in or near an area that the state federal or tribal governments have designated as having historic or cultural preservation status (e g National Historic Trust designation or properties significant in North Carolina history and archaeology)? ❑ Yes ❑ No 7b What data sources did you use to determine whether your site would impact historic or archeological resources? 8 Flood Zone Designation (Corps Requirement) 8a Will this project occur in a FEMA designated 100 year floodplain? ❑ Yes ❑ No 8b If yes explain how project meets FEMA requirements 8c What source(s) did you use to make the floodplain determination? Applicant/Agent s Printed Name Date Applicant/Agent s Signature (Agents signature is valid only if an authorization letter from the applicant is provided Page 10 of 10 PCN Form — Version 1 3 December 10 2008 Version o�oF W .n rF9Q� NCDENR ` STORMWATER MANAGEMENT PERMIT APPLICATION FORM 401 CERTIFICATION APPLICATION FORM WETLAND SUPPLEMENT This form must be filled out printed and submitted The Required Items Checklist (Part III) must be punted filled out and submitted along with all the required information I PROJECT INFORMATION Project name Eagle Rock Concrete Contact name Hunter Freeman Phone number 919 469 3340 Date December 22 2011 Drainage area number 1 II DESIGN INFORMATION Site Characteristics n Drainage area 103 237 00 ft2 III Impervious area 76 230 00 ft2 Percent Impervious Design rainfall depth 738/ / 100 inch �~�` A SS 4 Iy� i Peak Flow Calculations i 1 yr 24 hr rainfall depth 291 In _ 028942 1 yr 24 hr Intensity 494 In/hr ;..y * c Pre - development 1 yr 24 hr runoff 071 ft3 /sec *G I NE 4�,�t�� tt off jt/sec �� l C PreJPost 1 yr 24 hr peak control 0071 00 ft3 /sec �ti11 Storage Volume Non SA Waters Minimum required volume 614700 ft3 Volume provided (temporary pool volume) 6 882 00 ft3 OK Storage Volume SA Waters Parameters 15' runoff volume ft3 Pre - development 1 yr 24 hr runoff volume ft3 Past development 1 yr 24 hr runoff volume ft3 Mmnmum volume required ft3 Volume provided ft3 OWet Design Depth of temporary pool /ponding depth (Dpi, t) 12 00 In OK Orawdown time 2 33 days OK Diameter of orifice 150 In OK Coefficient of discharge (Co) used In onfice diameter 0 60 (unrtless) calculation Driving head (Ho) used In the orifice diameter calculation 0 33 ft Provide calculations to support this driving head Form SW401 Wetland Rev 6 11/16/09 Parts I and 11 Project Design Summary Page 1 of 4 Surface Areas of Wetland Zones Surface Area of Entire Wetland Shallow Land The shallow land percentage is Shallow Water The shallow water percentage is Deep Pool Forebay portion of deep pool (pretreatment) The forebay surface area percentage is Non forebay portion of deep pool The non forebay deep pool surface area percentage is Total of wetland zone areas Add or subtract the following area from the zones Topographic Zone Elevations Temporary Pool Elevation (TPE) Shallow Land (top) Permanent Pool Elevation (PPE) Shallow Water /Deep Pool (top) Shallow Water bottom Most shallow point of deep pool s bottom Deepest point of deep pool s bottom Design must meet one of the following two options This design meets Option #1 Top of PPE is within 6 of SHWT If yes SHWT (Seasonally High Water Table) This design meets Option #2 Wetland has liner with permeability < 0 01 in/hr If yes Depth of topsoil above impermeable liner Topographic Zone Depths Temporary Pool Shallow Land Permanent Pool Shallow Water Deep Pool (shallowest) Deep Pool (deepest) Planting Plan Are cattails included in the planting plan? Number of Plants recommended in Shallow Water Area Herbaceous (4 cubic inch container) Number of Plants recommended in Shallow Land Area Herbaceous (4 cubic inch container) OR Shrubs (1 gallon or larger) OR Trees (3 gallon or larger) and Herbaceous (4+ cubic inch) Number of Plants provided in Shallow Water Area Herbaceous (4 cubic inch container) Number of Plants provided in Shallow Land Area Herbaceous (4 cubic inch container) Shrubs (1 gallon or larger) Trees (3 gallon or larger) and Grass like Herbaceous (4+ cubic inch) 7 200 00 ft2 OK 2 875 00 ff2 OK 40/ / 2 875 00 ff2 OK 40/ / 300 00 ff2 Insufficient forebay area 4/ / UY. 1-0 -- 1 150 00 ft2 Insufficient non forebay deep pool area 16/ / 7 200 00 ft2 OK 0 00 ft2 370 00 ft amsl 369 00 ft amsl 368 50 ft amsl 367 00 ft amsl 366 00 ft amsl N (Y or N) ft amsl OK Y (Y or N) 4 00 in OK 12 00 in OK 6 00 in OK 24 00 in OK 36 00 in OK N (Y or N) OK 750 750 120 15 and 600 720 Higher density is required 7 M h4h- 652 More required if not planting shrubs or trees 68 More required if not planting herb and/or trees Form SW401 Wetland Rev 6 11/16/09 Parts I and 11 Project Design Summary Page 2 of 4 Additional Information Can the design volume be contained? Y (Y or N) OK Does project drain to SA waters? if yes N (Y or N) Excess volume must pass through filter What Is the length of the vegetated filter? It Are calculations for supporting the design volume provided In the Y (Y or N) OK application? Is BMP sized to handle all runoff from ultimate build out? Y (Y or N) OK Is the BMP located In a recorded drainage easement with a Y (Y or N) OK recorded access easement to a public Right of Way (ROW)? The length to width ratio is 200 1 OK Approximate wetland length 110 00 ft Approximate wetland width 55 00 ft Approximate surface area using length and width provided 6 050 00 ftz This approx surface area is within this number of square feet of the entire wetland surface area reported above WIII the wetland be stabilized within 14 days of construction? Y (Y or N) OK Form SW401 Wetland Rev 6 11/16/09 Parts I and 11 Project Design Summary Page 3 of 4 Permit No (to be provided by DWQ) III REQUIREDITEMS CHECKLIST u µ 4 A Please Indicate the page or plan sheet numbers where the supporting documentation can be found An Incomplete submittal package will result In a request for additional Information This will delay final review and approval of the project Initial In the space provided to Indicate the following design requirements have been met If the applicant has designated an agent the agent may Initial below If a requirement has not been met attach justification Initials Pagel Plan Sheet No 2 1 Plans (1 50 or larger) of the entire site showing Design at ultimate build out Off site drainage (if applicable) Delineated drainage basins (Include Rational C coefficient per basin) Wetland dimensions (and length to width ratio) Pretreatment system Maintenance access Proposed drainage easement and public right of way (ROW) Overflow device and Boundaries of drainage easement G 2 Plan details (1 =50 or larger) for the wetland showing Wetland dimensions (and length to width ratio) Pretreatment system Maintenance access Proposed drainage easement and public right of way (ROW) Design at ultimate build out Off site drainage (if applicable) Overflow device and Boundaries of drainage easement *^ 3 Section view of the wetland (1 = 20 or larger) showing Side slopes 31 or lower Wetland layers All wetlands Shallow land depth shallow water depth deep pool depth Option 1 no clay liner SLWT depth Option 2 clay liner Depth of topsoil on top of liner liner specifications C 4 A detailed planting plan (1 = 20 or larger) prepared by a qualified Individual showing A variety of several suitable species (not including cattails) Sizes spacing and locations of plantings Total quantity of each type of plant specified Pt4u A planting detail The source nursery for the plants and Fertilizer and watering requirements to establish vegetation C 6 5 A construction sequence that shows how the wetland will be protected from sediment until the entire drainage area Is stabilized _ 6 The supporting calculations (Including drawdown calculations) _ 7 A copy of the signed and notarized operation and maintenance (0 &M) agreement Af a 8 A copy of the deed restrictions (if required) _ A 9 A soils report that is based upon an actual field Investigation and soil borings County soil maps are not an CLAT L, LJ „ - acceptable source of soils information SW401 Wetland Rev 6 11/16/09 Part III page 4 of 4 d WITHE RS RAVENEL STORMWATER MANAGEMENT , �U1 Eagle Rock Concrete SUP SP 11 03 Garner, North Carolina Prepared For ® @ RJ O D EAGLE ROCK 8310 Bandford Way DEC 201 Raleigh NC 27614 DENR WATERGUALITf Attn Adam Loftin ETLANDOANDSTORMWATERBFANCH Prepared By WITHERS & RAVENEL, INC iii MacKenan Drive Cary North Carolina 27511 November 2011 W &R Project No 2110380 R ,� V C Ro viii SEAL = ,r 942 C. �i��yr�RG I N 114,7�� Hunter C Freem EAGLE ROCK CONCRETE STORMWATER MANAGEMENT REPORT GARNER, NORTH CAROLINA INTRODUCTION The proposed Eagle Rock Concrete Plant Is located approximately one mile SE of the Intersection of US Interstate 4o and US Highway 7o The development site is currently wooded and undeveloped and is part of the Greenfield South subdivision The development will consist of a ready mix concrete manufacturing facility with associated office building parking lots storage areas and paved yard for associated yard activities This development is subject to the North Carolina Division of Water Quality Neuse River Basin rules for stormwater management and the Town of Garner stormwater management ordinance in addition to NCG 14 which serves as the industrial facility wastewater permit for ready mix concrete activities The purpose of this report is to demonstrate the site s proposed compliance with these regulations The on site soils consist primarily of Appling sandy loams with small areas of Altavista fine sandy loam and Worsham sandy loams The Appling sandy loams which comprise over go% of the site including all areas of land development activity have a hydrologic soil group (HSG) classification of B Based on the soil types and land uses within pre and post development drainage areas composite curve numbers (CN) were developed for each drainage area A soils map of the site can be found in the Background section of this report STORMWATER MANAGEMENT AND INDUSTRIAL WASTEWATER REQUIREMENTS Because the proposed development contains a proposed ready mix concrete plant the proposed site plan Includes grading to ensure that there is no mixing of stormater and wastewater Rainwater that falls onto the Industrial areas within the site is considered wastewater and is controlled and treated per the requirements of NCG14 This Industrial area is not considered In the nitrogen loading calculations but is Included in the peak flow calculations Additional permitting will be coordinated with NCDWQ for review and approval of the proposed wastewater treatment plan In addition to review of the diffuse flow plan per Neuse River Buffer regulation requirements STORMWATER MANAGEMENT REQUIREMENTS Because the proposed development is within the Neuse River Basin non Industrial areas of the site must meet the requirements relating to the Neuse River Basin rules To meet these requirements the Nitrogen export from a commercial site must be reduced to the target level of 3 6o lbs /ac /yr This may be accomplished through the use of Best Management Practices (BMP) exclusively or it may be calculated and reduced to less than 10 oo lbs /ac /yr using BMPs supplemented by a buy down payment made to the North Carolina Ecosystem Enhancement Program to offset the nitrogen export to the 3 6o lbs /ac /yrtarget level The Greenfield South subdivision submitted an overall nitrogen management strategy in 2oo6 which Included a offset payment for 424 24 lbs /yr of nitrogen A portion of the buydown will be used to offset nitrogen from this parcel to reach the target level approved In the original master plan Onsite nitrogen reduction will be achieved with use of a constructed stormwaterwetland which has been sized to accomdate runoff from all non industrial areas of the site The proposed wetland provides 40% removal of Total Nitrogen The wetland will treat runoff from approximately 2 37 acres of the development site of which 74% Is impervious (paved areas and rooftop) The remaining impervious portion of the site consists of the industrial activity area and is covered under NCG 14 Eagle Rock Concrete W &R Project 2110380 Stormwater Management Report November 2011 EAGLE ROCK CONCRETE STORMWATER MANAGEMENT REPORT GARNER NORTH CAROLINA Runoff from these areas will be directed to settling chambers a wastewater treatment system and Finally to a pipe storage device priorto discharge The discharges from this system will be monitored for compliance with NCG14 as outlined in the approved permit (to be submitted for review by NCDWQ in a separate package from this report) All runoff from the proposed site including runoff from the areas that bypass the BMP was considered in the peak flow calculations The Town of Garner Unified Development Ordinance stormwater management section requires attenuation of the peak flowrates resulting from the 1 10 25 and loo year storm events The ordinance requires post development peak flowrates be attenuated to the predevelopment flowrates associated with these storms Detention requirements may be reduced or eliminated by the Town if it can be shown that reduced or eliminated detention will not create adverse impacts downstream of the development site and that by delaying the post development site peak flow the overall watershed peak flow will increase A summary of the detention analysis is included in the appendices of this report METHODOLOGY The stormwater study was conducted using the natural drainage features as depicted by Wake County LIDAR topography (1 ft contours) and existing field surveys Proposed drainage areas were based on field survey data and proposed development within the drainage areas The scope of work included the following analyses Hydrology ❑ Simulation of the 1 year 10 year 25 year and loo year rainfall events for the Garner NC area ❑ Formulation of the 1 year zo year 25 year and loo year flood hydrographs for the pre and post development drainage areas Hydraulic ❑ Routing the 1 year 10 year 25 year and loo year flood hydrographs for predevelopment runoff from the site ❑ Routing the 1 year 10 year 25 year and loo year flood hydrographs for post development runoff through the proposed stormwater wetland and underground storage structure ❑ Analyzing results at the downstream analysis point The results of the hydrology calculations are used in the hydraulic analyses The hydraulic design requires the development of a stage storage and stage discharge function for the proposed BMPs The rainfall /runoff hydrographs stage storage and stage discharge functions have been compiled to create a computer routing simulation model using Haestad Methods PondPack v10 o software This PondPack model was then used to assess the peak water surface elevations in the BMPs for the design rainfall events The outflow from the BMPs was then combined with the bypass runoff for total site runoff analysis The PondPack modeling results are provided as appendices to this report HYDROLOGY The SCS Method in conjunction with NOAA Atlas 14 rainfall data for Raleigh Durham International Airport was used to develop runoff hydrographs for the 1 year 10 year 25 year and loo year storm Eagle Rock Concrete W &R Project 2110380 Stormwater Management Report November 2011 EAGLE ROCK CONCRETE STORMWATER MANAGEMENT REPORT GARNER NORTH CAROLINA events This method requires three basic parameters a curve number (CN) time of concentration (t) and drainage area Curve numbers were based on soil type and land use Soil types were delineated from the Soil Survey of Wake County North Carolina (November 197o) The curve numbers used in this study are listed in the PondPack section of this report Time of concentration for pre and post development drainage areas was calculated using the Kirpich equation with a minimum time of concentration of 5 minutes HYDRAULICS Computer simulated reservoir routing of the 1 year 10 year 25 year and loo year design storms utilized stage storage and stage discharge functions Stage storage functions were derived from the proposed geometry of the stormwater wetland A non linear regression relation for surface area versus elevation was derived for the BMP This relation estimates the incremental volume of the basin to the stage or elevation of the basin Stage discharge functions were developed to size the proposed outlet structure for the BMP NITROGEN EXPORT The Nitrogen export was calculated using Method 2 from the NC DWQ methodologies for computing nitrogen loading for residential commercial and industrial developments when the entire footprint of the roads parking lots and buildings can be determined All drainage areas including offsite roadway improvements were used in the nitrogen export analysis The worksheet used to calculate the nitrogen export loading rate can be found in the appendices CONCLUSIONS Qualit Based upon the routing study the proposed stormwater management plan has sufficient measures to provide the necessary removal of Total Nitrogen required by the NC DWQ Neuse River Basin rules Furthermore the proposed BMP has sufficient storage to safely pass the loo year storm event without overtopping The proposed BMP was designed to store and treat the water quality volume (runoff associated with the first 1 of rainfall WQ„) generated by the contributing drainage area The outlet of the BMP was designed to discharge the WQ„ over 2 to 5 days to meet water quality guidelines Because the runoff resulting from the first 1 of rainfall is being discharged over 2 5 days a 40% Nitrogen reduction credit was taken for the area draining through the constructed wetland The BMP treatment resulted in bringing the total site s Nitrogen export down to 4 37 lbs /ac /yr Eagle Rock Concrete W &R Project 2110380 Stormwater Management Report November 2011 EAGLE ROCK CONCRETE STORMWATER MANAGEMENT REPORT GARNER NORTH CAROLINA DESIGN SUMMARY STORMWATER WETLAND DRAINAGE AREA = 2 37 ACRES PERCENT IMPERVIOUS AREA = 74% • 4 x 4 riser structure w/ crest @ 27190 • 2 Wide Attenuation Weir @ 271 00 • 15" WQv drawdown orifice @ 269 oo (N P elevation) • 2 attenuation orifice @ 270 oo (WQ Pool Elevation) • 24 RCP Outlet Barrel invert @ 264 00 • Top of Dam @ 272 50 PIPE STORAGE (DOWNSTREAM OF WEIR SYSTEM DRAINAGE AREA = 0 81 ACRES PERCENT IMPERVIOUS AREA =100% • 1oo LF 48 Pipe • Weir Wall at Downstream end 0 3" Orifice @ 265 00 o Overflow Weir @ 272 00 BYPASS AREA DRAINAGE AREA = 2 6 ACRES PERCENT IMPERVIOUS AREA = O% PERFORMANCE SUMMARY 100 YR PEAK WATER SURFACE ELEVATIONS Wetland loo yr Peak WSE = 272 02 Top of Dam = 272 50 Freeboard = 0 48 NITROGEN LOADING Total Area 5 77 Acres Estimated Project Pre BMP TN Export 40 37 lbs /yr Estimated Project BMP TN Removal 15 14 lbs /yr Estimated Project TN Load Rate After BMPs 4 37 lbs /ac /yr ** Note — Industrial Area Considered Open Space For Nitrogen Calculations Eagle Rock Concrete W &R Project 2110380 Stormwater Management Report November 2011 EAGLE ROCK CONCRETE STORMWATER MANAGEMENT REPORT GARNER, NORTH CAROLINA PEAK ATTENUATION Wetland Routine Summary vent Peak Water Surface Elevation Freeboard Qpeak Outflow (total) (�) (�) (cfs) ar F625 27052 198 014 ar 27141 log 170 ar 27168 0 82 3 34 F— ear 27202 048 7 84 Pine Storage Routine Summary FStvent Peak Water Surface Elevation Freeboard Qpeak Outflow (total) (ft) (ft) (cfs) 1 Year 26874 426 045 so Year 27259 041 326 25 Year 27270 030 400 IIE 100 Year 27280 020 473 Peak Attenuation Summary Eagle Rock Concrete W &R Protect 2110380 Stormwater Management Report November 2011 Post Development Post Development Net Change Peak Flow Peak Flow Peak Flow w /BMP (cfs) (cfs) (cfs) (cfs) FDevelopment o 71 9 57 0 71 0 00 7 41 21 90 6 08 133 1136 26 os 9 85 151 1718 3154 16 76 042 Eagle Rock Concrete W &R Protect 2110380 Stormwater Management Report November 2011 EAGLE ROCK CONCRETE STORMWATER MANAGEMENT REPORT GARNER NORTH CAROLINA BACKGROUND INFORMATION Eagle Rock Concrete W &R Project 2110380 Stormwater Management Report November 2011 .T- 7.0 wa ,t, �1 t f; Y' '• 5 F 455' Sy `ti� Q � 1, A 'S 5 5 �4 II J1 r r r� Eagle Rock Concrete 0 400 800 1600 Feet PIN 1730125497 Real Estate ID 0232219 Map Name 173003 Owner GREENFIELD 40 ASSOC LLC Mailing Address 1 901 OLD KNIGHT RD Mailing Address 2 KNIGHTDALE NC 27545 -9065 Mailing Address 3 Deed Book 12054 Deed Page 0742 Deed Date 7/1012006 Deeded Acreage 5.77 Assessed Building Value $0.00 Assessed Land Value $316,638.00 Total Assessed Value $316,638.00 Billing Class CORPORATE LISTING Property Description L01 MINOR SUB NONCONTIGUOUS LOTS GREENFIELD BM2006 -01121 Heated Area Site Address 2500 WATERFIELD DR City Township ST. MARYS Year Built 0 Total Sale Price $0.00 Sale Date Type and Use Design Style Land Class VACANT Old Parcel Number 000 -- WAKE COUNTY V, Name: GARNER Location: 035'40'55.45"N 078° 33' 31.42" W NAD27 Date: 11/1/2011 Caption: Eagle Rock Scale: 1 inch equals 2000 feet w y i' t • • r pa J-1 — 1 l4 . w.,.e•t� E • AOUI LA � r ,/ � j '...J � �` i .� 'A � . M burn 8cA yr , , l C f y t � w 4c.T ` J 1 � Y , Radio ow IWRA _T, 0 {� 315c, 0 x � ,71' {J �. 1� R , f Meld couil brook y Club 772 _ �bft a, Hern*u CA — i i 372 • r - tiii___rTS .t . i ° 35' no nn- W n7R' qA, nn nn° W n7Q° iv nn nn" �nr 078' 32' nn V, Name: GARNER Location: 035'40'55.45"N 078° 33' 31.42" W NAD27 Date: 11/1/2011 Caption: Eagle Rock Scale: 1 inch equals 2000 feet Precipitation Frequency Data Server NOAA Atlas 14 Volume 2 Version 3GARNER Station ID 31 3238 Location name Raleigh North Carolina US Coordinates 35 6708 78 6608 ¢ Elevation Elevation (station metadata) 330ft source Google Maps POINT PRECIPITATION FREQUENCY ESTIMATES G M Bonnin D Martin B Lin T Parzybok M Yekta and D Riley NOAH National Weather Service Sil or Spring Maryland PF tabular I PF graphical I Maps & aerials PF tabular Page 1 of 4 Back to Tog U 4,- /n.,1 -- .. .. , .. nL A-- 1- 11ZA-1 -41Z,7. �4n-Z1 17ZQR riot = rlar�4 11/11 /,)()11 PDS based point precipitation frequency estimates with 90% confidence intervals (in Inches)' Duration Average recurrence interval(years) 0�� 10 25 50 100 200 500 1000 0 412 0 481 0 551 0 615 0 680 0 730 0 775 0 814 0 858 0 895 5 min (0 377 0 450) (0 440 0 526) (0 505 0 603) (0 562 0 671) (0 619 0 742) (0 662 0 796) (0 698 0844 (0 729 0 888) (0 762 0 936) (0 789 0 979) 0 658 0 769 0 883 0 983 1 08 1 16 1 23 1 29 3641 10 min (0 602 0 719) (0 704 0 841) (0 809 0 966) (0 899 1 07) (0 987 1 18) (1 05 1 27) (1 11 134 ) ( 1 16 1 41 ) (1 21 4s) (1 24 54) 0 822 —IF-0-9-66----]F--, 12 1 24 1 37 1 47 1 56 1 63 --1-71---]F-1--77--I 15 min 1(0 753 0899) (0 885 106) 1 (102 122) 1 (1 14 136) 1 (125 150) 1 (1 33 161) 1 (1 40 170) 1 (146 178) 1 (152 1 86) 1 (1 56 194) 1 13 F-1-34-- 1 59 -18-0--T--2-04-T--2-22 2 38 -IF-2-53--]F-2-7-2--- 2 53 2 72 2 87 30 min (1 03 1 23) 1 (1 22 1 46) 1 (1 46 1 74) 1 (1 65 1 97) 1 (1 85 2 22) 1 (2 01 2 42) 1 (2 15 2 60) 1 (2 27 2 77) 1 (2 41 2 97) 1 (2 53 3 13) 1 41 F--i-68-j-_2 04 2 35 2 71 3 00 —3-28--IF— 28 55 —35-5--Jr— 3 90 418 60 min (1 29 154) 1 (153 1 83) 1 (1 87 2 23) 1 (2 15 2 56) 1 (2 47 2 96) 1 (2 72 3 28) 1 (2 96 3 58) 11 (3 19 3 88) 1 (3 46 4 26) 1 (3 69 4 57) 1 65 1 97 3 31 3 72 412 4 —52--IF--50-5 5 50 2 hr ( 1 50 1 82) (1 80 2 17 ) (2 2142 67) (2 56 3 10 ) (2 98 3 64) (3 34 4 08) (3 67 4 51) (4 00 4 95) (4 43 5 53) (4 78 6 03 ) 1 75 2 0-97--]F--2-58- 9 2 58 3 03 -35-9---]F-4 07 4 55 5 06 5 73 --6-32---1 3 hr (1 59 1 93) I (1 91 2 31) 1 (2 35 2 85) 1 (2 75 3 33) 1 (3 23 3 94) 1 (3 65 4 47) 1 (4 04 5 00) 1 (4 46 5 54) 1 (5 00 6 29) 1 (5 45 6 95) 2-09---]F--2-51-- 09 251 -3-09---IF--3 -63 432 492 553 61-6--1F--7-02--T--77-9---j 6 hr (1 92 2 30) 1 (2 29 2 76) 1 (2 83 3 40) 1 (3 31 3 98) 1 (3 91 4 73) 1 (4 42 5 38) 1 (4 92 6 03) 1 (5 43 6 72) 1 (6 11 7 66) 1 (6 69 8 50) F-2-4-6-- 2 95 3 66 4 32 5 17 5 93 6-7-0-- 7 52 8 66 9 68 12 hr (2 25 2 71) 11 (2 70 3 24) 1 (3 34 4 02) 1 (3 92 4 74) 1 (4 67 5 66) 1 (5 31 6 47) 1 (5 94 7 30) 1 (6 59 8 19) 1 (7 47 9 43) 1 (8 22 10 5) 291 351 442 514 612 -69-1---1 771 855 970 106 24 hr (2 69 3 14) 11 (3 25 3 80) 1 (4 09 4 79) 1 (4 74 5 56) 1 (5 63 6 63) 1 (6 33 7 47) 1 (7 79 9 25) 1 (8 80 10 5) 1 (9 59 11 5) 3 37 4 05 5 O7 5 87 6 96 7 83 8 72 9 64 10 9 11 9 2-day (3 12 3 63) (3 76 4 37) (4 69 5 47) (5 42 6 33 ) (6 42 7 50) 1 (7 19 8 44) 1 (7 99 9 40) 1 (8 80 10 4) 1 (9 91 11 8) 1 (10 8 12 9) 3 57 4 29 4 5 —34-IF- 616 7 29 8 19 911 10 1 11 4 12 4 3-day (3 31 3 84) 11 (3 98 4 62) 1 (4 95 5 74) 1 (5 70 6 62) 1 (6 73 7 83) 1 (7 53 8 80) 1 (8 35 9 79) 1 (9 20 10 8) 1 (10 3 12 2) 1 (11 2 13 4) 3 77 4 53 5 60 6 45 7 -6-1--T--8 54 9 50 —1057--T--1 0 5 - 11 8 12 9 4-day (3 51 4 05) 11 (4 21 4 86) 1 (5 21 6 01) 1 (5 98 6 91) 1 (7 04 8 16) 1 (7 88 9 16) 1 (8 72 10 2) 1 (9 60 11 2) 1 (10 8 12 7) 11 (11 7 13 9) 4 37 5 22 6 37 7 29 —8--55-- 9 56 10 6 11 6 13 1 14 2 T-day (4 07 4 68) 11 (4 86 5 59) 1 (5 94 6 83) 1 (6 79 7 81) 1 (7 93 9 16) 1 (8 84 10 2) 1 (9 76 11 3) 1 (10 7 12 5) 1 (12 0 14 1) 1 (13 0 15 3) 499 594 715 811 939 104 4 11-4--T--125---1F--139- 125 139 150 10-day (4 66 533) 1 (5 55 634) 1 (6 68 764) 1 (7 55 865) 1 (8 73 10 0) 1 (9 65 11 1) 1 (106 12 2) 1 (115 13 3) 1 (128 14 8) 1 (137 16 0) 668 790 -936---T-1-5-5--T-712 1 133 145 1-5 —7--11 174 187 20-day (6 25 715) 11 (7 38 845) 1 (8 73 10 0) 1 (9 79 112) 1 (112 12 9) 1 (123 14 2) 1 (134 15 5) 1 (145 16 8) 1 (160 186) 1 (172 201) 831 978 114 126 143 156 168 181 F-19-8-7F-21-0--- 198 210 30�tay (7 79 885) 1 (9 17 10 4) 1 (107 12 1) 1 (118 13 5) 1 (133 15 2) 1 (145 16 6) 1 (156 17 9) (168 193) 1 (183 21 1) 11 (194 22 5) 106 124 142 156 174 IF-18-8-7F- 188 202 -2-15-7F- 15 232 245 45-day (100 112) 11 (118 13 1) 1 (135 15 1) 1 (148 16 5) 1 (165 18 4) 1 (177 19 9) 1 (189 213) 1 (201 22 8) 1 (217 24 6) 1 (229 26 0) 127 148 168 203 218 232 246 264 278 60-day ( 120 134) (140 156) (159 177 ) (1738194 ) (191 215) (205 230) (218 246) (231 260) (247 280) (259 295 ) Precipitation frequency (PF) estimates in this table are based on frequency analysis of partial duration senes (PDS) Numbers in parenthesis are PF estimates at lower and upper bounds of the 90 / confidence interval The probability that precipitation frequency estimates (for a given duration and average recurrence interval) will be greater than the upper bound (or less than the lower bound) is 5/ Estimates at upper bounds are not checked against probable maximum precipitation (PMP) estimates and may be higher than currently valid PMP values Please refer to NOAA Atlas 14 document for more information Back to Tog U 4,- /n.,1 -- .. .. , .. nL A-- 1- 11ZA-1 -41Z,7. �4n-Z1 17ZQR riot = rlar�4 11/11 /,)()11 Precipitation Frequency Data Server NOAA Atlas 14 Volume 2 Version 3GARNER Station ID 31 3238 Location name Raleigh North Carolina US Coordinates 35 6708 78 6608 Elevation Elevation (station metadata) 330ft '`w source Google Maps POINT PRECIPITATION FREQUENCY ESTIMATES G M Bonn n D Martin B Lin T Parcybok M Yekta and D Riley NOAA National Weather Service Silver Spring Maryland PF tabular I PF graphical I Maps & aerials PF tabular Page 1 of 4 PDS based point precipitation frequency estimates with 90% confidence intervals (in inches /hour)1 Average recurrence interval(years) Duration 1 �� 2 5 10 25 50 100 200 500 1000 494 577 661 73-8-7F--8-16---1F--8 7-6 --jr--9-30--1F--97-7T- 930 977 103 107 5min (4 52 5 40) 1 (5 28 6 31) 1 (6 06 7 24) 1 (6 74 8 05) 1 (7 43 8 90) 1 (7 94 9 55) (8 38 10 1) 1 (8 75 10 7) 1 (9 14 11 2) 1 (9 47 11 7) 10 395 461 530 590 -6s-o--]F--697 739 774 814 845 min (3 61 4 31) (4 22 5 05) (4 85 5 80) (5 39 6 44) (5 92 7 10) (6 32 7 61) (6 65 8 05) (6 94 8 45) (7 23 8 89 ) (7 45 9 25 ) F--3-29-- 6 3 -86--T--4-47----1F--4-98- 4 47 4 98 5 50 5 88 2 6 —22-T- -65-1T--6-8-3--T--708--j 15 min (3 01 3 60) (3 54 4 23) (4 10 4 89) (4 55 5 43) (5 00 6 00) (5 34 6 42) (5 61 6 78) (5 84 7 10) (6 07 7 46 ) ( 6 24 7 74) 2 25 2 67 3 17 3 60 4 O7 -44-3-T- 43 5 07 5 43 5 73 30 min (2 06 2 46) (2 45 2 92) (2 91 3 47) (3 29 3 94) (3 71 4 44 ) ( 4 02 4 84 ) (4 29751s ) (4 54 5 53) (4 83 5 93 ) (5 05 6 27) F-1-4-17-17 -16-8---]F--2 04 2 35 2 71 3 00 3 —28-F-3-55-- 8 3 55 3 90 418 60 min (1 29 1 54) (1 53 1 83) 1 (1 87 2 23) 1 (2 15 2 56) 1 (2 47 2 96) 11 (2 72 3 28) 1 (2 96 3 58) 1 (3 19 3 88) 1 (3 46 4 26) 1 (3 69 4 57) F--08-24-- -0-9-8-61F--1 21 1 41 -16-6---T--1-86--T--2 06 2 26 -25-2--- 2 75 2 hr (0 750 0 909) (0 899 1 09) 1 (1 10 1 34) 1 (1 28 1 55) 1 (1 49 1 82) 1 (1 67 2 04) 1 (1 83 2 26) 1 (2 00 2 48) 1 (2 21 2 77) 1 (2 39 3 02) 0 581 0 696 -0-8-60-- -1-0 1 20 1 68 1 91 211 3 hr 213fi49) (0 530 0 641) (0 636 0 769) (0 782 0 949) (0 915 1 11 ) ( 1 08 1 31 ) (1 (1 s5?ss ) (1 48 1 85) 1 (1 66 2 09) 1 (1 82 2 31) F-0-34-9 0 418 -0-5-1-7--]F-O-6-0-6 0 722 -0-8-22---]F-09-2-3---I F-70 -171-7-- 1 30 6 hr (0 320 0 384) (0 383 0 460) (0 472 0 567@0 552 0 665) (0 653 0 790) (0 738 0 898) (0 822 1 01) (0 906 1 12) 1 (1 02 1 28) 1 (1 12 1 42) 0 204 0 245 0 303 0 358 0 429 0 492 0 556 0 624 0 719 0 803 12 hr (0 187 0 225) (0 224 0 269@0 277 0 334) (0 325 0 393@0 387 0 470) (0 440 0 537) (0 493 0 606) (0 547 0 680@0 620 0 782) (0 682 0 874) 0121 0 146 0 184 0 214 0 255 —0-2-88---]F-0-32-1 0 356 0 404 0 442 24 hr (0 112 0 131) (0 135 0 158) (0 170 0 199) (0 197 0 232) (0 235 0 276) (0 264 0 311) (0 294 0 348) (0 325 0 385) (0 367 0 437) (0 399 0 479) 0 070 0 084 0 106 0 122 0 145 0 163 0182 0 201 0 227 0 248 2 day (0 065 0 076) (0 078 0 091@0 098 0 114@0 113 0 132) (0 134 0 156) (0 150 0 176@0 166 0 196) (0 183 0 217@0 206 0 245) (0 224 0 268) 0 050 0 060 0 074 0 086 —010-1--]F-0-1-14-- 101 0114 0126 0140 0158 0172 3-day (0 046 0 053) (0 055 0 064) (0 069 0 080) (0 079 0 092) (0 093 0 109) (0 105 0 122) (0 116 0 136) (0 128 0 150) (0 144 0 170) (0 156 0 186) 0 039 0 047 0 058 0 067 0 079 0 089 0 099 —515-9-T-6-123 0134 4-day (0 037 0 042@0 044 0 051) (0 054 0 063) (0 062 0 072) (0 073 0 085) (0 082 0 095) (0 091 0 106) (0 100 0 117) (0 112 0 132) (0 122 0 144) 0 026 0 031 0 038 0 043 0 051 0 057 0 063 0 069 0 078 -0-08-5---I 7-day (0 024 0 028) (0 029 0 033@0 035 0 041) (0 040 0 046) (0 047 0 055@0 053 0 061@0 058 0 068) (0 064 0 074) (0 071 0 084) (0 077 0 091) 0 021 0 -02511 0 030 0 034 —003-9-IF--O043--IF 0 048 0 052 —005-8--IF-00-62--1 10-da y (0 019 0 022) (0 023 0 026) (0 028 0 032) (0 031 0 036) (0 036 0 042) (0 040 0 046) (0 044 0 051) (0 048 0 056) (0 053 0 062@0 057 0 067) F-001-4 0 016 0 019 0 022 0 025 0 028 6 030 0 033 0 036 0 039 20 da y (0 013 0 015) (0 015 0 018) (0 018 0 021) (0 020 0 023) (0 023 0 027) (0 026 0 030) (0 028 0 032) (0 030 0 035) (0 033 0 039) (0 036 0 042) F-001-2 0 014 0 016 0 018 0 020 0 022 0 023 0 025 0 027 —0-0 2- 029 30-da y (0 011 0 012) (0 013 0 014) (0 015 0 017) (0 016 0 019) (0 019 0 021) (0 020 0 023) (0 022 0 025) (0 023 0 027) (0 025 0 029) (0 027 0 031) 0010 0011 0013 0014 0016 0017 0019 0020 0021 0023 45-day (0 009 0 010) (0 011 0 012) (0 012 0 014) (0 014 0 015) (0 015 0 017) (0 016 0 018@0 018 0 020) (0 019 0 021@0 020 0 023) (0 021 0 024) 0009 0010 0012 0013 0014 0015 0016 0017 7 7-5 01-8T-5 0019 5-1- 60-day (0 008 0 009) (0 010 0 011) (0 011 0 012) (0 012 0 013) (0 013 0 015) (0 014 0 016) (0 015 0 017) (0 016 0 018) (0 017 0 019) (0 018 0 020) ' Precipitation frequency (PF) estimates in this table are based on frequency analysis of partial duration series (PDS) Numbers in parenthesis are PF estimates at lower and upper bounds of the 90 / confidence interval The probability that precipitation frequency estimates (for a given duration and average recurrence interval) will be greater than the upper bound (or less than the lower bound) is 5/ Estimates at upper bounds are not checked against probable maximum precipitation (PMP) estimates and may be higher than currently valid PMP values Please refer to NOAA Atlas 14 document for more information Back to Top U++— ln.A — — ..---- -- /L.,7..- 1-- P.1,1 —f'.1 . o +,'21 Z7'IQR ilot��ntan 117 /7 ()1 1 EAGLE ROCK CONCRETE STORMWATER MANAGEMENT REPORT GARNER NORTH CAROLINA BMP SIZING CALCULATIONS Eagle Rock Concrete W &R Project 2110380 Stormwater Management Report November 2011 Protect Name Eagle Rock Ci /State Garner NC STORMWATER BMP 1 STORMWATER WETLAND (40% TN Removal) Land Use Area (ac) % IA Imp Area (ac) Impervious 1 75 100 1 8 Open Space 062 0 0 0 Shallow Water 2459 2900 40/6 Totals 1 237 1 1 1 8 Total % Impervious Surface Area = 738 / Project # 2110384 Date 14 Nov 11 1 Inch Runoff Volume Calculation Using the runoff volume calculations in the Simple Method as described by Schueler (1987) Rv = 0 05 + 0 0090) where Rv = Runoff coefficient in /in I = Percent impervious Rv = 071 in /in Total runoff volume from 1 inch precipitation Runoff volume S = (Design rainfall) (Rv) (Drainage Area) S = 0 141 acre -ft 6147 cu ft Water quality pool elevation= 37000 feet Storage volume provided = 0 158 acre -ft 6882 cu ft Wetland Zone Areas (sq ft ) WQ Ponding Depth = 12 in Recommended Provided 7 of total Deep Pools & Forebays 1229 1450 2001 Shallow Land 2459 2845 400/ Shallow Water 2459 2900 40/6 Totals 6147 7195 100% Proiect Name Eagle Rock City/State Garner NC STORMWATER BMP WET POND (25% TN Removal) Orifice Calculator Q = Cd *A *(2gh) ^(1/2) Variables WQ Volume Head Draw down time Orifice Area = 0 158 Acre ft 1 00 ft 56 hrs 0 012281 sq ft Orifice Diameter = 1 500538 in USE 15 INCH DIAMETER ORIFICE 6882 48 cf 0 333333 ft 201600 s 1 768412 sq in Project # 2110384 Date 14 Nov 11 Constants g = 32 2 ft/S2 Cd = 06 Bentley Systems Inc Haestad Methods Solution Center Bentley FlowMaster [08 01 071 00] 12/22120116 24 07 AM 27 Siemons Company Drive Suite 200 W Watertown CT 06795 USA +1203 755 1666 Page 1 of 1 Wetland Bypass Protect Descnptlon Friction Method Manning Formula Solve For Normal Depth ,Input Data Roughness Coefficient 0 040 Channel Slope 002000 ft/ft Left Side Slope 300 ft/ft (H V) Right Side Slope 300 ft/ft (H V) Bottom Width 200 ft Discharge 1 70 ft /s Results Normal Depth 030 ft c Flow Area 088 ft J Wetted Perimeter 391 ft p OZ Top Width 381 ft Critical Depth 025 ft Critical Slope 004147 fl/ft C 3� Velocity 194 ft/s c Velocity Head 006 ft Specific Energy 036 ft Froude Number 071 Flow Type Subcntical GVF Input Data Downstream Depth 000 ft Length 000 ft Number Of Steps 0 GVF Output Data Upstream Depth 000 ft Profile Description Profile Headloss 000 ft Downstream Velocity Infinity ft/s Upstream Velocity Infinity ft/s Normal Depth 030 ft Critical Depth 025 ft Channel Slope 002000 ft/ft Critical Slope 004147 fti t Bentley Systems Inc Haestad Methods Solution Center Bentley FlowMaster [08 01 071 00] 12/22120116 24 07 AM 27 Siemons Company Drive Suite 200 W Watertown CT 06795 USA +1203 755 1666 Page 1 of 1 EAGLE ROCK CONCRETE STORMWATER MANAGEMENT REPORT GARNER NORTH CAROLINA PONDPACK ROUTING CALCULATIONS Eagle Rock Concrete W &R Project 2110380 Stormwater Management Report November 2011 Job File K \11 \11- 0380 \110380 -Eagle Rock Concrete \H -H \EAGLE ROCK 11 NOV 2011 PPW Rain Dir K \11 \11- 0380 \110380 -Eagle Rock Concrete \H -H\ JOB TITLE Project Date 11/1/2011 Project Engineer hfreeman Project Title Eagle Rock Concrete Project Comments SIN Bentley Systems Inc Bentley PondPack (10 00 027 00) 3 35 PM 11/15/2011 Table of Contents Table of Contents i * * MASTER SUMMARY Watershed Master Network Summary 1 01 * * * * DESIGN STORMS SUMMARY ** RDU NOAA 14 Desi Design Storms 2 01 ** * * TC CALCULATIONS * ** INDUSTRIAL Tc Calcs 3 01 POST TO BMP Tc Calcs 3 03 POST UNTREATED Tc Calcs 3 05 PRE DEVELOPMENT Tc Calcs 3 07 * CN CALCULATIONS INDUSTRIAL Runoff CN -Area 4 01 POST TO BMP Runoff CN -Area 4 02 POST UNTREATED Runoff CN -Area 4 03 PRE DEVELOPMENT Runoff CN -Area 4 04 * POND VOLUMES PIPE STORAGE Vol Elev - Volume 5 01 SIN Bentley PondPack (10 00 027 00) 3 35 PM Bentley Systems Inc 11/15/2011 Table of Contents Table of Contents (continued) SETTLING WEIR Vol E1ev -Area WETLAND Vol Elev -Area ** * * * * OUTLET STRUCTURES Pipe Splitter Outlet Input Data Composite Rating Curve Wetland Orifice Outlet Input Data Composite Rating Curve SIN Bentley PondPack (10 00 027 00) 3 35 PM * ii 5 02 5 03 * * 6 01 6 03 6 07 6 11 Bentley Systems Inc 11/15/2011 Type Master Network Summary Page 1 01 Name Watershed File K \11 \11- 0380 \110380 -Eagle Rock Concrete \H -H \Eagle Rock 11 Nov 2011 ppw MASTER DESIGN STORM SUMMARY Network Storm Collection RDU NOAA 14 Desi Total Depth Return Event in 10 4 9800 25 5 9000 100 7 3700 1 3 0000 Rainfall Type --------------- - Time -Depth Curve Time -Depth Curve Time -Depth Curve Synthetic Curve --------------------------- ICPM CALCULATION TOLERANCES Target Convergence= 000 cfs +/- Max Iterations = 35 loops ICPM Time Step = 0500 hrs Output Time Step = 0500 hrs ICPM Ending Time = ------------------------- 35 0000 - - - - hrs -- RNF ID RDU NOAA 10yr RDU NOAA 25yr RDU NOAA 100yr TypeII 24hr MASTER NETWORK SUMMARY SCS Unit Hydrograph Method ( Node = Outfall +Node = Diversion ) (Trun= HYG Truncation Blank =None L =Left R =Rt LR= Left &Rt) Max Qpeak Max WSEL Pond Storage cfs ft ac -ft -- - - - - -- -- - - - - -- ------ - - - - -- 5 25 5 78 6 43 3 07 OUT POST Return HYG Vol Qpeak Node ID ----------- - - - Type - -- Event - ac -ft Trun hrs INDUSTRIAL - - -- AREA - - - -- 10 ---- - - - - -- -- 320 --- - - - - -- 12 1000 INDUSTRIAL AREA 25 382 12 1000 INDUSTRIAL AREA 100 481 12 1000 INDUSTRIAL AREA 1 187 11 9000 Max Qpeak Max WSEL Pond Storage cfs ft ac -ft -- - - - - -- -- - - - - -- ------ - - - - -- 5 25 5 78 6 43 3 07 OUT POST JCT 10 1 215 12 2500 6 08 OUT POST JCT 25 1 556 12 2000 9 85 OUT POST JCT 100 2 130 12 2000 16 76 OUT POST JCT 1 557 12 0500 71 SIN Bentley PondPack (10 00 027 00) 3 35 PM Bentley Systems Inc 11/15/2011 Type Master Network Summary Page 1 02 Name Watershed File K \11 \11- 0380 \110380 -Eagle Rock Concrete \H -H \Eagle Rock 11 Nov 2011 ppw ------------------------------- ICPM CALCULATION TOLERANCES ------------------------------- Target Convergence= 000 cfs +/- Max Iterations = 35 loops ICPM Time Step = 0500 hrs Output Time Step = 0500 hrs ICPM Ending Time = 35 0000 hrs ------------------------- - - - - -- MASTER NETWORK SUMMARY SCS Unit Hydrograph Method ( Node = Outfall +Node = Diversion ) (Trun= HYG Truncation Blank =None L =Left R =Rt LR= Left &Rt) SIN Bentley PondPack (10 00 027 00) 3 35 PM Bentley Systems Inc 11/15/2011 Max Return HYG Vol Qpeak Qpeak Max WSEL Pond Storage Node ID Type Event ac -ft Trun hrs cfs ft ac -ft ----------- OUT - - - - -- PRE - - -- JCT - - - - -- 10 ---- - - - - -- -- 466 --- 12 - - - - -- 1000 -- - - - 7 - -- 41 -- - - - - -- ------ - - - - -- OUT PRE JCT 25 702 12 1000 11 36 OUT PRE JCT 100 1 136 12 1000 17 18 OUT PRE JCT 1 094 12 0500 71 PIPE STORAGE POND 10 296 12 1500 4 06 PIPE STORAGE POND 25 358 12 1500 4 55 PIPE STORAGE POND 100 457 12 1500 5 13 PIPE STORAGE POND 1 162 12 0500 1 88 PIPE STORAGE OUT POND 10 296 12 2500 3 26 272 59 031 PIPE STORAGE OUT POND 25 358 12 2000 4 00 272 70 031 PIPE STORAGE OUT POND 100 457 12 2000 4 73 272 80 032 PIPE STORAGE OUT POND 1 162 12 4000 45 268 74 027 POST TO BMP AREA 10 721 12 1000 13 32 POST TO BMP AREA 25 895 12 1000 15 14 POST TO BMP AREA 100 1 176 12 1000 17 40 POST TO BMP AREA 1 359 11 9000 6 50 POST UNTREATED AREA 10 209 12 1000 3 33 POST UNTREATED AREA 25 315 12 1000 5 10 POST UNTREATED AREA 100 510 12 1000 7 71 POST UNTREATED AREA 1 042 12 0500 32 SIN Bentley PondPack (10 00 027 00) 3 35 PM Bentley Systems Inc 11/15/2011 Type Master Network Summary Page 1 03 Name Watershed File K \11 \11- 0380 \110380 -Eagle Rock Concrete \H -H \Eagle Rock 11 Nov 2011 ppw ------------------------------- ICPM CALCULATION TOLERANCES ------------------------------- Target Convergence= 000 cfs +/- Max Iterations = 35 loops ICPM Time Step = 0500 hrs Output Time Step = 0500 hrs ICPM Ending Time = 35 0000 hrs ------------------------- - - - - -- MASTER NETWORK SUMMARY SCS Unit Hydrograph Method ( Node = Outfall +Node = Diversion ) (Trun= HYG Truncation Blank =None L =Left R =Rt LR= Left &Rt) SIN Bentley PondPack (10 00 027 00) 3 35 PM Bentley Systems Inc 11/15/2011 Max Return HYG Vol Qpeak Qpeak Max WSEL Pond Storage Node ID ----------- - - - -- Type Event ac -ft Trun hrs cfs ft ac -ft - PRE DEVELOPMENT - - -- AREA - - - - -- 10 ---- - - - - -- -- 466 --- 12 - - - - -- 1000 -- - - 7 - - -- 41 -- - - - - -- ------ - - - - -- PRE DEVELOPMENT AREA 25 702 12 1000 11 36 PRE DEVELOPMENT AREA 100 1 136 12 1000 17 18 PRE DEVELOPMENT AREA 1 094 12 0500 71 SETTLING WEIR POND 10 320 12 1000 5 25 SETTLING WEIR POND 25 382 12 1000 5 78 SETTLING WEIR POND 100 481 12 1000 6 43 SETTLING WEIR POND 1 187 11 9000 3 07 SETTLING WEIROUT POND 10 296 12 1500 4 06 276 45 085 SETTLING WEIROUT POND 25 358 12 1500 4 55 276 49 086 SETTLING WEIROUT POND 100 457 12 1500 5 13 276 54 087 SETTLING WEIROUT POND 1 162 12 0500 1 88 276 26 080 WETLAND IN POND 10 721 12 1000 13 32 WETLAND IN POND 25 895 12 1000 15 14 WETLAND IN POND 100 1 176 12 1000 17 40 WETLAND IN POND 1 359 11 9000 6 50 WETLAND OUT POND 10 710 12 5500 1 70 271 41 416 WETLAND OUT POND 25 883 12 3500 3 34 271 68 471 WETLAND OUT POND 100 1 164 12 2500 7 84 272 02 543 WETLAND OUT POND 1 353 14 7000 14 270 52 251 SIN Bentley PondPack (10 00 027 00) 3 35 PM Bentley Systems Inc 11/15/2011 Type Design Storms Page 2 01 Name RDU NOAA 14 Desi File K \11 \11- 0380 \110380 -Eagle Rock Concrete \H -H \Eagle Rock 11 Nov 2011 ppw Title Project Date 11/1/2011 Project Engineer hfreeman Project Title Eagle Rock Concrete Project Comments DESIGN STORMS SUMMARY Design Storm File ID = RDU NOAA 14 Desi Storm Tag Name = 10 Data Type File ID = Time -Depth Curve RDU NOAA 10yr Storm Frequency = 10 yr Total Rainfall Depth= 4 9800 in Duration Multiplier = 1 Resulting Duration = 23 9904 hrs Resulting Start Time= 0000 hrs Step= 0833 hrs End= 23 9904 hrs Storm Tag Name = 25 Data Type File ID = Time -Depth Curve RDU NOAA 25yr Storm Frequency = 25 yr Total Rainfall Depth= 5 9000 in Duration Multiplier = 1 Resulting Duration = 23 9904 hrs Resulting Start Time= 0000 hrs Step= 0833 hrs End= 23 9904 hrs Storm Tag Name = 100 Data Type File ID = Time -Depth Curve RDU NOAA 100yr Storm Frequency = 100 yr Total Rainfall Depth= 7 3700 in Duration Multiplier = 1 Resulting Duration = 23 9990 hrs Resulting Start Time= 0000 hrs Step= 0833 hrs End= 23 9990 hrs Storm Tag Name = 1 Data Type File ID = Storm Frequency = Total Rainfall Depth= Duration Multiplier = Resulting Duration = Resulting Start Time= Synthetic Storm TypeII 24hr 1 yr 3 0000 in 1 24 0000 hrs 0000 hrs Step= 1000 hrs End= 24 0000 hrs SIN Bentley Systems Inc Bentley PondPack (10 00 027 00) 3 35 PM 11/15/2011 Type Tc Calcs Page 3 01 Name INDUSTRIAL File K \11 \11- 0380 \110380 -Eagle Rock Concrete \H -H \Eagle Rock 11 Nov 2011 ppw TIME OF CONCENTRATION CALCULATOR Segment #1 Tc User Defined Segment #1 Time 0830 hrs ------------------------------------------------------------------ - - - - -- ------------------------- ------------------------- Total Tc 0830 hrs Calculated Tc < Min Tc Use Minimum Tc Use Tc = 0833 hrs ------------------------- ------------------------- SIN Bentley Systems Inc Bentley PondPack (10 00 027 00) 3 35 PM 11/15/2011 Type Tc Calcs Page 3 02 Name INDUSTRIAL File K \11 \11- 0380 \110380 -Eagle Rock Concrete \H -H \Eagle Rock 11 Nov 2011 ppw ------------------------------------------------------------------------ Tc Equations used ------------------------------------------------------------------ - - - - -- = = == User Defined Tc = Value entered by user Where Tc = Time of concentration S/N Bentley Systems Inc Bentley PondPack (10 00 027 00) 3 35 PM 11/15/2011 Type Tc Calcs Page 3 03 Name POST TO BMP File K \11 \11- 0380 \110380 -Eagle Rock Concrete \H -H \Eagle Rock 11 Nov 2011 ppw TIME OF CONCENTRATION CALCULATOR Segment #1 Tc User Defined Segment #1 Time 0830 hrs ------------------------------------------------------------------ - - - - -- SIN Bentley PondPack (10 00 027 00) ------------------------- ------------------------- Total Tc 0830 hrs Calculated Tc < Min Tc Use Minimum Tc Use Tc = 0833 hrs 3 35 PM Bentley Systems Inc 11/15/2011 Type Tc Calcs Page 3 04 Name POST TO BMP File K \11 \11- 0380 \110380 -Eagle Rock Concrete \H -H \Eagle Rock 11 Nov 2011 ppw ------------------------------------------------------------------------ Tc Equations used ------------------------------------------------------------------ - - - - -- ___= User Defined = _____ - - - - -- Tc = Value entered by user Where Tc = Time of concentration S/N Bentley Systems Inc Bentley PondPack (10 00 027 00) 3 35 PM 11/15/2011 Type Tc Calcs Page 3 05 Name POST UNTREATED File K \11 \11- 0380 \110380 -Eagle Rock Concrete \H -H \Eagle Rock 11 Nov 2011 ppw TIME OF CONCENTRATION CALCULATOR Segment #1 Tc User Defined Segment #1 Time 0830 hrs ------------------------------------------------------------------ - - - - -- SIN Bentley PondPack (10 00 027 00) Total Tc 0830 hrs Calculated Tc < Min Tc Use Minimum Tc Use Tc = 0833 hrs ------------------------ ------------------------ 3 35 PM Bentley Systems Inc 11/15/2011 Type Tc Calcs Page 3 06 Name POST UNTREATED File K \11 \11- 0380 \110380 -Eagle Rock Concrete \H -H \Eagle Rock 11 Nov 2011 ppw ------------------------------------------------------------------------ Tc Equations used ------------------------------------------------------------------ - - - - -- ___= User Defined _ ______ ------- __________ Tc = Value entered by user Where Tc = Time of concentration SIN Bentley Systems Inc Bentley PondPack (10 00 027 00) 3 35 PM 11/15/2011 Type Tc Calcs Page 3 07 Name PRE DEVELOPMENT File K \11 \11- 0380 \110380 -Eagle Rock Concrete \H -H \Eagle Rock 11 Nov 2011 ppw TIME OF CONCENTRATION CALCULATOR Segment #1 Tc User Defined Segment #1 Time 0830 hrs ------------------------------------------------------------------ - - - - -- SIN Bentley PondPack (10 00 027 00) Total Tc 0830 hrs Calculated Tc < Min Tc Use Minimum Tc Use Tc = 0833 hrs 3 35 PM Bentley Systems Inc 11/15/2011 Type Tc Calcs Page 3 08 Name PRE DEVELOPMENT File K \11 \11- 0380 \110380 -Eagle Rock Concrete \H -H \Eagle Rock 11 Nov 2011 ppw ------------------------------------------------------------------------ Tc Equations used ------------------------------------------------------------------ - - - - -- ___= User Defined ========-===--====_____ ______ = = = = = =____ ---- ___________ Tc = Value entered by user Where Tc = Time of concentration SIN Bentley Systems Inc Bentley PondPack (10 00 027 00) 3 35 PM 11/15/2011 Type Runoff CN -Area Page 4 01 Name INDUSTRIAL File K \11 \11- 0380 \110380 -Eagle Rock Concrete \H -H \Eagle Rock 11 Nov 2011 ppw RUNOFF CURVE NUMBER DATA Impervious Area Adjustment Adjusted Soil /Surface Description CN acres %C %UC CN -------------------------- - - - - -- - - -- --- - - - - -- - - - -- - - - -- - - - - -- Industrial Impervious 98 810 98 00 COMPOSITE AREA & WEIGHTED CN - - -> 810 98 00 (98) SIN Bentley PondPack (10 00 027 00) 3 35 PM Bentley Systems Inc 11/15/2011 Type Runoff CN -Area Page 4 02 Name POST TO BMP File K \11 \11- 0380 \110380 -Eagle Rock Concrete \H -H \Eagle Rock 11 Nov 2011 ppw RUNOFF CURVE NUMBER DATA Area Soil /Surface Description CN acres -------------------------- - - - - -- - - -- --- - - - - -- Impervious 98 1 750 Open Space 61 620 COMPOSITE AREA & WEIGHTED CN - - -> 2 370 Impervious Adjustment Adjusted %C sUC CN - - - -- - - - -- - - - - -- 98 00 61 00 88 32 (88) S/N Bentley Systems Inc Bentley PondPack (10 00 027 00) 3 35 PM 11/15/2011 Type Runoff CN -Area Page 4 03 Name POST UNTREATED File K \11 \11- 0380 \110380 -Eagle Rock Concrete \H -H \Eagle Rock 11 Nov 2011 ppw RUNOFF CURVE NUMBER DATA -------------------------------------------------------------------------- Impervious Area Adjustment Adjusted Soil /Surface Description CN acres QC %UC CN -------------------------- - - - - -- - - -- --- - - - - -- - - - -- - - - -- - - - - -- Woods - good 55 2 590 55 00 COMPOSITE AREA & WEIGHTED CN - - -> 2 590 SIN Bentley PondPack (10 00 027 00) 3 35 PM 55 00 (55) Bentley Systems Inc 11/15/2011 Type Runoff CN -Area Page 4 04 Name PRE DEVELOPMENT File K \11 \11- 0380 \110380 -Eagle Rock Concrete \H -H \Eagle Rock 11 Nov 2011 ppw RUNOFF CURVE NUMBER DATA Impervious Area Adjustment Adjusted Soil /Surface Description CN acres %C I-UC CN -------------------------- - - - - -- - - -- --- - - - - -- - - - -- - - - -- - - - - -- Woods - good 55 5 770 55 00 COMPOSITE AREA & WEIGHTED CN - - -> 5 770 55 00 (55) SIN Bentley Systems Inc Bentley PondPack (10 00 027 00) 3 35 PM 11/15/2011 Type Vol Elev - Volume Page 5 01 Name PIPE STORAGE File K \11 \11- 0380 \110380 -Eagle Rock Concrete \H -H \Eagle Rock 11 Nov 2011 ppw USER DEFINED VOLUME RATING TABLE Elevation Volume (ft) --------------- (ac -ft) - - - - -- 265 00 000 265 10 000 265 20 000 265 30 000 265 40 000 265 50 001 265 60 001 265 70 002 265 80 002 265 90 003 266 00 004 266 10 005 266 20 005 266 30 006 266 40 007 266 50 008 266 60 009 266 70 009 266 80 010 266 90 011 267 00 012 267 10 013 267 20 014 267 30 015 267 40 016 267 50 017 267 60 018 267 70 019 267 80 019 267 90 020 268 00 021 268 10 022 268 20 023 268 30 024 268 40 024 268 50 025 268 60 026 268 70 026 268 80 027 268 90 028 269 00 028 269 10 028 269 20 029 269 30 029 269 40 029 269 50 029 277 00 035 SIN Bentley PondPack (10 00 027 00) 3 35 PM Bentley Systems Inc 11/15/2011 Type Vol Elev -Area Page 5 02 Name SETTLING WEIR File K \11 \11- 0380 \110380 -Eagle Rock Concrete \H -H \Eagle Rock 11 Nov 2011 ppw Elevation Planimeter Area Al +A2 +sgr(Al A2) Volume Volume Sum (ft) ------------------------------------------------------------------------ (sq in) (sq ft) (sq ft) (ac -ft) (ac -ft) 273 00 - - - -- 880 0 000 000 277 00 - - - -- 1280 3221 099 099 POND VOLUME EQUATIONS Incremental volume computed by the Conic Method for Reservoir Volumes Volume = (1/3) (EL2 -EL1) (Areal + Area2 + sq rt (Areal Area2)) where ELI EL2 = Lower and upper elevations of the increment Areal Area2 = Areas computed for ELI EL2 respectively Volume = Incremental volume between ELI and EL2 SIN Bentley Systems Inc Bentley PondPack (10 00 027 00) 3 35 PM 11/15/2011 Type Vol Elev -Area Page 5 03 Name WETLAND File K \11 \11- 0380 \110380 -Eagle Rock Concrete \H -H \Eagle Rock 11 Nov 2011 ppw Elevation Planimeter Area Al +A2 +sgr(A1 A2) Volume Volume Sum (ft) ------------------------------------------------------------------------ (sq in) (sq ft) (sq ft) (ac -ft) (ac -ft) 269 00 - - - -- 4500 0 000 000 269 05 - - - -- 7000 17112 007 007 270 00 - - - -- 7196 21293 155 161 271 00 - - - -- 8205 23085 177 338 272 00 - - - -- 9271 26198 200 538 272 50 - - - -- 10000 28900 111 649 POND VOLUME EQUATIONS Incremental volume computed by the Conic Method for Reservoir Volumes Volume = (1/3) (EL2 -ELl) (Areal + Area2 + sq rt (Areal Area2)) where EL1 EL2 = Lower and upper elevations of the increment Areal Area2 = Areas computed for EL1 EL2 respectively Volume = Incremental volume between ELl and EL2 SIN Bentley PondPack (10 00 027 00) 3 35 PM Bentley Systems Inc 11/15/2011 Type Outlet Input Data Page 6 01 Name Pipe Splitter File K \11 \11- 0380 \110380 -Eagle Rock Concrete \H -H \Eagle Rock 11 Nov 2011 ppw REQUESTED POND WS ELEVATIONS Min Elev = 265 00 ft Increment = 10 ft Max E1ev = 277 00 ft OUTLET CONNECTIVITY - - -> Forward Flow Only (Upstream to DnStream) < - -- Reverse Flow Only (DnStream to UpStream) < - - -> Forward and Reverse Both Allowed Structure No Outfall El ft E2 ft ----------- - - - - -- - - -- - - - - - -- --- - - - - -- --- - - - - -- Orifice- Circular 00 - - -> TW 265 000 277 000 Weir - Rectangular WO - - -> TW 272 000 277 000 TW SETUP DS Channel S/N Bentley PondPack (10 00 027 00) 3 35 PM Bentley Systems Inc 11/15/2011 Type Outlet Input Data Page 6 02 Name Pipe Splitter File K \11 \11- 0380 \110380 -Eagle Rock Concrete \H -H \Eagle Rock 11 Nov 2011 ppw OUTLET STRUCTURE INPUT DATA Structure ID = 00 Structure Type = Orifice - Circular ------------------------------------ # of Openings = 1 Invert E1ev = 265 00 ft Diameter = 2500 ft Orifice Coeff = 600 Structure ID Structure Type -------- - - - - -- # of Openings Crest E1ev Weir Length Weir Coeff wo Weir- Rectangular ---------------- 1 272 00 ft 2 00 ft 3 100000 Weir TW effects (Use adjustment equation) Structure ID = TW Structure Type = TW SETUP DS Channel ------------------------------------ FREE OUTFALL CONDITIONS SPECIFIED CONVERGENCE TOLERANCES Maximum Iterations= 40 Min TW tolerance = 01 ft Max TW tolerance = 01 ft Min HW tolerance = 01 ft Max HW tolerance = 01 ft Min Q tolerance = 00 cfs Max Q tolerance = 00 cfs SIN Bentley Systems Inc Bentley PondPack (10 00 027 00) 3 35 PM 11/15/2011 Type Composite Rating Curve Page 6 03 Name Pipe Splitter File K \11 \11- 0380 \110380 -Eagle Rock Concrete \H -H \Eagle Rock 11 Nov 2011 ppw * COMPOSITE OUTFLOW SUMMARY WS E1ev Total Q Notes ---------- - - - - -- -- - - - - -- Converge - - - - --------------------- Elev Q TW Elev Error ft -- - - - - -- cfs - - - - ft + / -ft Contributing Structures 265 00 - -- 00 -- - - - Free - -- - - - -- Outfall -------------------- - - - - -- None contributing 265 10 02 Free Outfall 00 265 20 06 Free Outfall 00 265 30 10 Free Outfall 00 265 40 12 Free Outfall 00 265 50 14 Free Outfall 00 265 60 16 Free Outfall 00 265 70 18 Free Outfall 00 265 80 19 Free Outfall 00 265 90 21 Free Outfall 00 266 00 22 Free Outfall 00 266 10 23 Free Outfall 00 266 20 24 Free Outfall 00 266 30 26 Free Outfall 00 266 40 27 Free Outfall 00 266 50 28 Free Outfall 00 266 60 29 Free Outfall 00 266 70 30 Free Outfall 00 266 80 31 Free Outfall 00 266 90 31 Free Outfall 00 267 00 32 Free Outfall 00 267 10 33 Free Outfall 00 267 20 34 Free Outfall 00 267 30 35 Free Outfall 00 267 40 36 Free Outfall 00 267 50 36 Free Outfall 00 267 60 37 Free Outfall 00 267 70 38 Free Outfall 00 267 80 39 Free Outfall 00 267 90 39 Free Outfall 00 268 00 40 Free Outfall 00 268 10 41 Free Outfall 00 268 20 41 Free Outfall 00 268 30 42 Free Outfall 00 268 40 43 Free Outfall 00 268 50 43 Free Outfall 00 268 60 44 Free Outfall 00 268 70 45 Free Outfall 00 SIN Bentley Systems Inc Bentley PondPack (10 00 027 00) 3 35 PM 11/15/2011 Type Composite Rating Curve Page 6 04 Name Pipe Splitter File K \11 \11- 0380 \110380 -Eagle Rock Concrete \H -H \Eagle Rock 11 Nov 2011 ppw SIN Bentley Systems Inc Bentley PondPack (10 00 027 00) 3 35 PM 11/15/2011 * COMPOSITE OUTFLOW SUMMARY WS Elev Total Q Notes ---------- - - - - -- -- - - - - -- Converge ------------------------- Elev Q TW Elev Error ft cfs ft + / -ft Contributing Structures -- - - 268 - - -- 80 - - - - - -- 45 -- - - - Free - -- - - - -- Outfall -------------------- 00 - - - - -- 268 90 46 Free Outfall 00 269 00 47 Free Outfall 00 269 10 47 Free Outfall 00 269 20 48 Free Outfall 00 269 30 48 Free Outfall 00 269 40 49 Free Outfall 00 269 50 49 Free Outfall 00 269 60 50 Free Outfall 00 269 70 51 Free Outfall 00 269 80 51 Free Outfall 00 269 90 52 Free Outfall 00 270 00 52 Free Outfall 00 270 10 53 Free Outfall 00 270 20 53 Free Outfall 00 270 30 54 Free Outfall 00 270 40 54 Free Outfall 00 270 50 55 Free Outfall 00 270 60 55 Free Outfall 00 270 70 56 Free Outfall 00 270 80 56 Free Outfall 00 270 90 57 Free Outfall 00 271 00 57 Free Outfall 00 271 10 58 Free Outfall 00 271 20 58 Free Outfall 00 271 30 59 Free Outfall 00 271 40 59 Free Outfall 00 271 50 60 Free Outfall 00 271 60 60 Free Outfall 00 271 70 61 Free Outfall 00 271 80 61 Free Outfall 00 271 90 61 Free Outfall 00 272 00 62 Free Outfall 00 +WO 272 10 82 Free Outfall 00 +WO 272 20 1 17 Free Outfall 00 +WO 272 30 1 62 Free Outfall 00 +WO 272 40 2 14 Free Outfall 00 +WO 272 50 2 72 Free Outfall 00 +WO SIN Bentley Systems Inc Bentley PondPack (10 00 027 00) 3 35 PM 11/15/2011 Type Composite Rating Curve Page 6 05 Name Pipe Splitter File K \11 \11- 0380 \110380 -Eagle Rock Concrete \H -H \Eagle Rock 11 Nov 2011 ppw COMPOSITE OUTFLOW SUMMARY WS Elev Total Q Notes ---------- - - - - -- -- - - - - -- Converge ------------------------- Elev Q TW E1ev Error ft -- - - - - -- cfs ft + / -ft Contributing Structures 272 60 - - - - 3 - -- 35 -- - - - Free - -- - - - -- Outfall -------------------- 00 - - - - -- +WO 272 70 4 03 Free Outfall 00 +WO 272 80 4 74 Free Outfall 00 +WO 272 90 5 48 Free Outfall 00 +WO 273 00 6 24 Free Outfall 00 +WO 273 10 7 03 Free Outfall 00 +WO 273 20 7 84 Free Outfall 00 +WO 273 30 8 67 Free Outfall 00 +WO 273 40 9 51 Free Outfall 00 +WO 273 50 10 37 Free Outfall 00 +WO 273 60 11 23 Free Outfall 00 +WO 273 70 12 10 Free Outfall 00 +WO 273 80 12 97 Free Outfall 00 +WO 273 90 13 85 Free Outfall 00 +WO 274 00 14 73 Free Outfall 00 +WO 274 10 15 61 Free Outfall 00 +WO 274 20 16 49 Free Outfall 00 +WO 274 30 17 37 Free Outfall 00 +WO 274 40 18 24 Free Outfall 00 +WO 274 50 19 10 Free Outfall 00 +WO 274 60 19 96 Free Outfall 00 +WO 274 70 20 81 Free Outfall 00 +WO 274 80 21 65 Free Outfall 00 +WO 274 90 22 48 Free Outfall 00 +WO 275 00 23 29 Free Outfall 00 +WO 275 10 24 10 Free Outfall 00 +WO 275 20 24 88 Free Outfall 00 +WO 275 30 25 66 Free Outfall 00 +WO 275 40 26 41 Free Outfall 00 +WO 275 50 27 15 Free Outfall 00 +WO 275 60 27 87 Free Outfall 00 +WO 275 70 28 57 Free Outfall 00 +WO 275 80 29 25 Free Outfall 00 +WO 275 90 29 90 Free Outfall 00 +WO 276 00 30 54 Free Outfall 00 +WO 276 10 31 15 Free Outfall 00 +WO 276 20 31 74 Free Outfall 00 +WO 276 30 32 30 Free Outfall 00 +WO SIN Bentley Systems Inc Bentley PondPack (10 00 027 00) 3 35 PM 11/15/2011 Type Composite Rating Curve Page 6 06 Name Pipe Splitter File K \11 \11- 0380 \110380 -Eagle Rock Concrete \H -H \Eagle Rock 11 Nov 2011 ppw WS Elev Total Q Elev Q ft cfs -- - - - 276 - -- 40 - - - - - 32 -- 84 276 50 33 35 276 60 33 83 276 70 34 29 276 80 34 71 276 90 35 11 277 00 35 47 COMPOSITE OUTFLOW SUMMARY - - - - - -- Conver, TW Elev Error ft + / -ft Free Outfall Free Outfall Free Outfall Free Outfall Free Outfall Free Outfall Free Outfall SIN Bentley PondPack (10 00 027 00) Notes je----------------------- Contributing Structures 00 +WO 00 +WO 00 +WO 00 +WO 00 +WO 00 +w0 00 +WO 3 35 PM Bentley Systems Inc 11/15/2011 Type Outlet Input Data Page 6 07 Name Wetland Orifice File K \11 \11- 0380 \110380 -Eagle Rock Concrete \H -H \Eagle Rock 11 Nov 2011 ppw REQUESTED POND WS ELEVATIONS Min Elev = 269 00 ft Increment = 10 ft Max Elev = 272 50 ft S/N Bentley PondPack (10 00 027 00) 3 35 PM Bentley Systems Inc 11/15/2011 OUTLET CONNECTIVITY - - -> Forward Flow Only (Upstream to DnStream) < - -- Reverse Flow Only (DnStream to UpStream) < - - -> Forward and Reverse Both Allowed Structure ----------- - - - - -- - No - -- Outfall E1 ft E2 ft Orifice- Circular 02 - - -> - - - - - -- CO --- - - 270 - - -- --- 000 - 272 - - - -- 500 Weir- Rectangular WO - - -> CO 271 000 272 500 Inlet Box RO - - -> CO 271 900 272 500 Orifice- Circular 00 - - -> CO 269 000 272 500 Culvert - Circular CO - - -> TW 264 000 272 500 TW SETUP DS Channel S/N Bentley PondPack (10 00 027 00) 3 35 PM Bentley Systems Inc 11/15/2011 Type Outlet Input Data Page 6 08 Name Wetland Orifice File K \11 \11- 0380 \110380 -Eagle Rock Concrete \H -H \Eagle Rock 11 Nov 2011 ppw OUTLET STRUCTURE INPUT DATA Structure ID = 02 Structure Type = Orifice-Circular ------------------------------------ # of Openings = 1 Invert Elev = 270 00 ft Diameter = 1700 ft Orifice Coeff = 600 Structure ID Structure Type -------- - - - - -- # of Openings Crest Elev Weir Length Weir Coeff wo Weir- Rectangular ---------------- 1 271 00 ft 2 00 ft 3 000000 Weir TW effects (Use adjustment equation) Structure ID = RO Structure Type = Inlet Box ------------------------------------ # of Openings = 1 Invert Elev = 271 90 ft Orifice Area = 16 0000 sq ft Orifice Coeff = 600 Weir Length = 15 00 ft Weir Coeff = 3 100 K Reverse = 1 000 Mannings n = 0000 Kev Charged Riser = 000 Weir Submergence = No SIN Bentley Systems Inc Bentley PondPack (10 00 027 00) 3 35 PM 11/15/2011 Type Outlet Input Data Page 6 09 Name Wetland Orifice File K \11 \11- 0380 \110380 -Eagle Rock Concrete \H -H \Eagle Rock 11 Nov 2011 ppw OUTLET STRUCTURE INPUT DATA Structure ID = 00 Structure Type = Orifice- Circular ------------------------------------ # of Openings = 1 Invert Elev = 269 00 ft Diameter = 1200 ft Orifice Coeff = 600 Structure ID = CO Structure Type = ------------------------------------ Culvert - Circular No Barrels = 1 Barrel Diameter = 2 0000 ft Upstream Invert = 264 00 ft Dnstream Invert = 261 00 ft Horiz Length = 78 00 ft Barrel Length = 78 06 ft Barrel Slope = 03846 ft /ft OUTLET CONTROL DATA Mannings n = 0130 Ke = 5000 (forward entrance loss) Kb = 012411 (per ft of full flow) Kr = 5000 (reverse entrance loss) HW Convergence = 001 +/- ft INLET CONTROL DATA Equation form = 1 Inlet Control K = 0018 Inlet Control M = 2 0000 Inlet Control c = 02920 Inlet Control Y = 7400 T1 ratio (HW /D) = 1 043 T2 ratio (HW /D) = 1 188 Slope Factor = - 500 Use unsubmerged inlet control Form 1 equ below Tl elev Use submerged inlet control Form 1 equ above T2 elev In transition zone between unsubmerged and submerged inlet control interpolate between flows at T1 & T2 At T1 Elev = 266 09 ft - - -> Flow = 15 55 cfs At T2 Elev = 266 38 ft - - -> Flow = 17 77 cfs SIN Bentley Systems Inc Bentley PondPack (10 00 027 00) 3 35 PM 11/15/2011 Type Outlet Input Data Page 6 10 Name Wetland Orifice File K \11 \11- 0380 \110380 -Eagle Rock Concrete \H -H \Eagle Rock 11 Nov 2011 ppw OUTLET STRUCTURE INPUT DATA Structure ID = TW Structure Type = TW SETUP DS Channel ------------------------------------ FREE OUTFALL CONDITIONS SPECIFIED CONVERGENCE TOLERANCES Maximum Iterations= 40 Min TW tolerance = 01 ft Max TW tolerance = 01 ft Min HW tolerance = 01 ft Max HW tolerance = 01 ft Min Q tolerance = 00 cfs Max Q tolerance = 00 cfs SIN Bentley Systems Inc Bentley PondPack (10 00 027 00) 3 35 PM 11/15/2011 Type Composite Rating Curve Page 6 11 Name Wetland Orifice File K \11 \11- 0380 \110380 -Eagle Rock Concrete \H -H \Eagle Rock 11 Nov 2011 ppw * COMPOSITE OUTFLOW SUMMARY WS Elev Total Q Notes ---------- - - - - -- -- - - - - -- Converge ------------------------- Elev Q TW Elev Error ft cfs ft + / -ft Contributing Structures -- - - 269 - - -- 00 - - - - - -- 00 -- - - - Free - -- - - - -- Outfall -------------------- (no Q 02 WO RO 00 - - - - -- CO) 269 10 01 Free Outfall 00 CO (no Q 02 WO RO) 269 20 02 Free Outfall 00 CO (no Q 02 WO RO) 269 30 03 Free Outfall 00 CO (no Q 02 WO RO) 269 40 03 Free Outfall 00 CO (no Q 02 WO RO) 269 50 04 Free Outfall 00 CO (no Q 02 WO RO) 269 60 04 Free Outfall 00 CO (no Q 02 WO RO) 269 70 04 Free Outfall 00 CO (no Q 02 WO RO) 269 80 05 Free Outfall 00 CO (no Q 02 WO RO) 269 90 05 Free Outfall 00 CO (no Q 02 WO RO) 270 00 05 Free Outfall 00 CO (no Q 02 WO RO) 270 10 07 Free Outfall 02 00 CO (no Q WO RO) 270 20 10 Free Outfall 02 00 CO (no Q WO RO) 270 30 11 Free Outfall 02 00 CO (no Q WO RO) 270 40 12 Free Outfall 02 00 CO (no Q WO RO) 270 50 14 Free Outfall 02 00 CO (no Q WO RO) 270 60 15 Free Outfall 02 00 CO (no Q WO RO) 270 70 16 Free Outfall 02 00 CO (no Q WO RO) 270 80 16 Free Outfall 02 00 CO (no Q WO RO) 270 90 17 Free Outfall 02 00 CO (no Q WO RO) 271 00 18 Free Outfall 02 00 CO (no Q WO RO) 271 10 38 Free Outfall 02 WO 00 CO (no Q RO) 271 20 72 Free Outfall 02 WO 00 CO (no Q RO) 271 30 1 16 Free Outfall 02 WO 00 CO (no Q RO) 271 40 1 67 Free Outfall 02 WO 00 CO (no Q RO) 271 50 2 23 Free Outfall 02 WO 00 CO (no Q RO) 271 60 2 85 Free Outfall 02 WO 00 CO (no Q RO) 271 70 3 50 Free Outfall 02 WO 00 CO (no Q RO) 271 80 4 19 Free Outfall 02 WO 00 CO (no Q RO) 271 90 4 90 Free Outfall 02 WO 00 CO (no Q RO) 272 00 7 12 Free Outfall 02 WO RO 00 CO 272 10 10 56 Free Outfall 02 WO RO 00 CO 272 20 14 84 Free Outfall 02 WO RO 00 CO 272 30 19 76 Free Outfall 02 WO RO 00 CO 272 40 25 26 Free Outfall 02 WO RO 00 CO 272 50 31 22 Free Outfall 02 WO RO 00 CO SIN Bentley PondPack (10 00 027 00) 3 35 PM Bentley Systems Inc 11/15/2011 Appendix A Index of Starting Page Numbers for ID Names - - - -- I - - - -- INDUSTRIAL 3 01 4 01 - - - -- P - - - -- Pipe Spli.tter PIPE STORAGE POST TO BMP POST UNTREATED PRE DEVELOPMENT 6 01 6 03 5 01 3 03 4 02 3 05 4 03 3 07 4 04 - - - -- R - - - -- RDU NOAA 14 Desi - - - -- S - - - -- SETTLING WEIR - - - -- W - - - -- Watershed 1 01 WETLAND 5 03 Wetland Orifice 2 01 5 02 6 07 6 11 SIN Bentley PondPack (10 00 027 00) 3 35 PM A -1 Bentley Systems Inc 11/15/2011