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HomeMy WebLinkAboutSW8040215_HISTORICAL FILE_20030303STORMWATER DIVISION CODING SHEET POST -CONSTRUCTION PERMITS PERMIT NO. SW8 D4 02 15 DOC TYPE ❑ CURRENT PERMIT ❑ APPROVED PLANS HISTORICAL FILE ❑ COMPLIANCE EVALUATION INSPECTION DOC DATE 2003 03 03 YYYYMMDD State Stormwater Management Systems Permit No. SW8 040215 STATE OF NORTH CAROLINA DEPARTMENT OF ENVIRONMENT AND NATURAL DIVISION OF WATER QUALITY STATE STORMWATER MANAGEMENT PERMIT HIGH DENSITY DEVELOPMENT In accordance with the provisions of Article 21 of Chapter 143, General Statutes of North Carolina as amended, and other applicable Laws, Rules, and Regulations PERMISSION IS HEREBY GRANTED TO Hunter & Bundy Eastern Aluminum Storage Facility Onslow County FOR THE construction, operation and maintenance of a wet detention pond in compliance with the provisions of 15A NCAC 2H .1000 (hereafter referred to as the "stormwater rules') and the approved stormwater management plans and specifications and other supporting data as attached and on file with and approved by the Division of Water Quality and considered a part of this permit. This permit shall be effective from the date of issuance until March 3, 2014, and shall be subject to the following specified conditions and limitations: I. DESIGN STANDARDS This permit is effective only with respect to the nature and volume of stormwater described in the application and other supporting data. 2. This stormwater system has been approved for the management of stormwater runoff as described on page 3 of this permit, the Project Data Sheet. The stormwater control has been designed to handle the runoff from 52,228 square feet of impervious area. This pond must be operated with a vegetated filter. 3. The tract will be limited to the amount of built -upon area indicated on page 3 of this permit, and per approved plans. The built -upon area for the future development is limited to 7,500 square feet. 4. All stormwater collection and treatment systems must be located in either dedicated common areas or recorded easements. The final plats for the project will be recorded showing all such required easements, in accordance with the approved plans. 5. The runoff from all built -upon area within the permitted drainage area of this project must be directed into the permitted stormwater control system. A permit modification must be submitted and approved prior to the construction of additional built -upon area from outside of the approved drainage area. State Stormwater Management Systems Permit No. SW8 040215 DIVISION OF WATER QUALITY PROJECT DESIGN DATA SHEET Project Name: Permit Number: Location: Applicant: Mailing Address: Application Date: Receiving Stream/River Basin: Stream Index Number: Classification of Water Body: Drainage Area, acres: Onsite, sq. ft.: Offsite, sq. ft.: Total Impervious Surfaces, sq. ft.: Pond Depth, feet: TSS removal efficiency: Permanent Pool Elevation, FMSL: Permitted Surface Area, sq. ft.: Permitted Storage Volume, cubic ft.: Temporary Storage Elevation, FMSL: Controlling Orifice: Permitted Forebay Volume, cubic ft.: Eastern Aluminum Storage Facility SW8 040215 Onslow County Mr. Jay Bundy, General Partner Hunter & Bundy P.O. Box 11540 Goldsboro, NC 27532 March 3, 2004 Northeast Creek / White Oak 19-16-(0.5) "SC NSW" 1.70 74,052 none, per engineer 52,228 5.0 85% (a 30' vegetated filter is required) 39.0 2,98 1 @Permanent Pool 5,283 40.51 1" � (drawdown in 2-5 days) 1,202 3 State Stormwater Management Systems Permit No. SW8 040215 Il. SCHEDULE OF COMPLIANCE The stormwater management system shall be constructed in its entirety, vegetated and operational for its intended use prior to the construction of any built -upon surface. During construction, erosion shall be kept to a minimum and any eroded areas of the system will be repaired immediately. The permittee shall at all times provide the operation and maintenance necessary to assure the permitted stormwater system functions at optimum efficiency. The approved Operation and Maintenance Plan must be followed in its entirety and maintenance must occur at the scheduled intervals including, but not limited to: a. Semiannual scheduled inspections (every 6 months). b. Sediment removal. C. Mowing and revegetation of slopes and the vegetated filter. d. Immediate repair of eroded areas. C. Maintenance of all slopes in accordance with approved plans and specifications. f. Debris removal and unclogging of outlet structure, orifice device, flow spreader, catch basins and piping. g. Access to the outlet structure must be available at all times. 4. Records of maintenance activities must be kept and made available upon request to authorized personnel of DWQ. The records will indicate the date, activity, name of person performing the work and what actions were taken. Decorative spray fountains will be allowed in the stormwater treatment system, subject to the following criteria: a. The fountain draws its water from less than 2' below the permanent pool surface. b. Separated units, where the nozzle, pump and intake are connected by tubing, may be used only if they draw water from the surface in the deepest part of the pond. C. The falling water from the fountain must be centered in the pond, away from the shoreline. d. The maximum horsepower for the fountain's pump is based on the permanent pool volume. The maximum pump power for a fountain in this pond is 1 /8 horsepower. 6. The facilities shall be constructed as shown on the approved plans. This permit shall become voidable unless the facilities are constructed in accordance with the conditions of this permit, the approved plans and specifications, and other supporting data. Upon completion of construction, prior to issuance of a Certificate of Occupancy, and prior to operation of this permitted facility, a certification must be received from an appropriate designer for the system installed certifying that the permitted facility has been installed in accordance with this permit, the approved plans and specifications, and other supporting documentation. Any deviations from the approved plans and specifications must be noted on the Certification. A modification may be required for those deviations. 8. If the stormwater system was used as an Erosion Control device, it must be restored to design condition prior to operation as a stormwater treatment device, and prior to occupancy of the facility. 9. The penmittee shall submit to the Director and shall have received approval for revised plans, specifications, and calculations prior to construction, for any modification to the approved plans, including, but not limited to, those listed below: 4 State Stormwater Management Systems Permit No. SW8 040215 a. Any revision to any item shown on the approved plans, including the stormwater management measures, built -upon area, details, etc. b. Project name change. C. Transfer of ownership. d. Redesign or addition to the approved amount of built -upon area or to the drainage area. C. Further subdivision, acquisition, or sale of all or part of the project area. The project area is defined as all property owned by the permittee, for which Sedimentation and Erosion Control Plan approval or a CAMA Major permit was sought. f. Filling in, altering, or piping of any vegetative conveyance shown on the approved plan. 10. The permittee shall submit final site layout and grading plans for any permitted future areas shown on the approved plans, prior to construction. If the proposed BUA exceeds the amount permitted under this permit, a modification to the permit must be submitted and approved prior to construction. 11. A copy of the approved plans and specifications shall be maintained on file by the Permittee for a minimum of ten years from the date of the completion of construction. 12. At least 30 days prior to the sale or lease of any portion of the property, the permittee shall notify DWQ and provide the name, mailing address and phone number of the purchaser or leasee. An access/maintenance easement to the stormwater facilities shall be granted in favor of the permittee if access to the stormwater facilities will be restricted by the sale or lease of any portion of the property. 13. The permittee must maintain compliance with the proposed built -upon area and ensure that the runoff from all the built -upon is directed into the permitted system. 14. The Director may notify the permittee when the permitted site does not meet one or more of the minimum requirements of the permit. Within the time frame specified in the notice, the penmittee shall submit a written time schedule to the Director for modifying the site to meet minimum requirements. The permittee shall provide copies of revised plans and certification in writing to the Director that the changes have been made. 15. The permittee must maintain the current permitted drainage area. No additional runoff from outside of the permitted drainage area boundary may enter the permitted stormwater facilities without first applying for and receiving a permit modification. 111. GENERAL CONDITIONS This permit is not transferable except after notice to and approval by the Director. In the event of a change of ownership, or a name change, the permittee must submit a formal permit transfer request to the Division of Water Quality, accompanied by a completed name/ownership change form, documentation from the parties involved, and other supporting materials as may be appropriate. The approval of this request will be considered on its merits and may or may not be approved. The permittee is responsible for compliance with all permit conditions until such time as the Division approves the transfer request. 2. Failure to abide by the conditions and limitations contained in this permit may subject the Permittee to enforcement action by the Division of Water Quality, in accordance with [North Carolina General Statute 143-215.6A to 143-215.6C. 3. The issuance of this permit does not preclude the Permittee from complying with any and all statutes, rules, regulations, or ordinances which may be imposed by other government agencies (local, state, and federal) which have jurisdiction. State Stormwater Management Systems Permit No. SW8 040215 In the event that the facilities fail to perform satisfactorily, including the creation of nuisance conditions, the Permittee shall take immediate corrective action, including those as may be required by this Division, such as the construction of additional or replacement stormwater management systems. 5. The permittee grants DENR Staff permission to enter the property during normal business hours for the purpose of inspecting all components of the permitted stonmwater management facility. The permit may be modified, revoked and reissued or terminated for cause. The filing of a request for a permit modification, revocation and reissuance or termination does not stay any permit condition. 7. Unless specified elsewhere, permanent seeding requirements for the stormwater control must follow the guidelines established in the North Carolina Erosion and Sediment Control Planning and Design Manual. Approved plans and specifications for this project are incorporated by reference and are enforceable parts of the permit. 9. The permittee shall notify the Division any name, ownership or mailing address changes within 30 days. Permit issued this the 3rd day of March 2004. NORTH CAROLINA ENVIRONMENTAL MANAGEMENT COMMISSION Alan W. Klimek, P.., Director Division of Water Quality By Authority of the Environmental Management Commission State Stormwater Management Systems Permit No. SW8 040215 Eastern Aluminum Storage Facility Stormwater Permit No. SW8 040215 Onslow County Designer's Certification as a duly registered in the State of North Carolina, having been authorized to observe (periodically/weekly/full time) the construction of the project, (Project) for (Project Owner) hereby state that, to the best of my abilities, due care and diligence was used in the observation of the project construction such that the construction was observed to be built within substantial compliance and intent of the approved plans and specifications. The checklist of items on page 2 of this form is included in the Certification. Noted deviations from approved plans and specification: SEAL Signature Registration Number Date State Stormwater Management Systems Permit No. SW8 040215 Certification Requirements: 1. The drainage area to the system contains approximately the permitted acreage. 2. The drainage area to the system contains no more than the permitted amount of built -upon area. 3. All the built -upon area associated with the project is graded such that the runoff drains to the system. 4. The outlet/bypass structure elevations are per the approved plan. 5. The outlet structure is located per the approved plans. 6. Trash rack is provided on the outlet/bypass structure. 7. All slopes are grassed with permanent vegetation. 8. Vegetated slopes are no steeper than 3:1. 9. The inlets are located per the approved plans and do not cause short-circuiting of the system. 10. The permitted amounts of surface area and/or volume have been provided. H. Required drawdown devices are correctly sized per the approved plans. 12. All required design depths are provided. 13. All required parts of the system are provided, such as a vegetated shelf, and a forebay. 14. The overall dimensions of the system, as shown on the approved plans, are provided. cc: NCDENR-DWQ Regional Office Onslow County Building Inspections Consulting Engineers and Land Surveyors March 2, 2004 Ms. Laurie Munn Dept. of Environment and Natural Resources Water Quality Section RECEIVED 127 Cardinal Drive, Ext Wilmington, NC 28405-3845 MAR 0 3 2004 Q� Subject: Express Stormwater Management Eastern Aluminum Storage Facility Onslow County Proj. # 040133 Dear Ms. Munn: Enclosed for your review and approval, please find the following items: Two (2) copies of the revised plans. Two (2) copies of the revised sheet 2 of the application with all impervious areas broken into square footage. Two (2) copies of the calculations with the engineer's seal. (252) 335-1888 Office (252) 338-2913 Office (252) 338-5552 Fax If you have any questions or require additional information, please do not hesitate to call this office at (252) 335-1888. cc: file Sincerely, Sean C. Robey, P.E. Kimberly D. Hamby Engineering Assistant 150-A US Highway 158 East, Camden, NC 27921 I w ATF9 f, • Mr. Jay Bundy Hunter & Bundy P.O. Box 11540 Goldsboro, NC 27532 Dear Mr. Bundy: Michael F. Easley, Governor William G. Ross Jr., Secretary North Carolina Department of Environment and Natural Resources Alan W. Klimek, P.E.,Director Division of Water Quality Coleen H. Sullins, Deputy Director Division of Water Quality February 23, 2004 Subject: REQUEST FOR ADDITIONAL INFORMATION Stormwater Project No. SW8 040215 Eastern Aluminum Storage Facility Onslow County The Wilmington Regional Office received a Stormwater Management Permit Application for Eastern Aluminum Storage Facility on February 23, 2004. A preliminary review of that information has determined that the application is not complete. The following information is needed to continue the stormwater review: 1. Please either delineate all wetlands on site, disturbed or undisturbed, or note on the plans that none exist. ✓ 2. Please add the nearest intersection of two major roads to the vicinity map. A major road is any 1, 2 or 3 digit NC, US or interstate highway. ,/ 3. Please specify the pond vegetation and the wetland species to be planted on the 6:1 shelf. ✓4. Please provide a 3:1 L: W flow path ratio in the pond. ✓5. Please dimension the permanent pool contour. / 6. Please delineate the drainage area to the pond. The application lists 2 drainage basins for this project. The drainage delineation map should show both of these basins. ✓ 7. Please provide a 30' vegetative filter at the outlet of the pond. Also, please add a vegetative filter detail for the plans. I have included a copy of the detail. ✓ 8. Please seal the calculations. ✓ 9. Please report all built -upon areas in square feet on the application. Please separate the future proposed area from the square footage shown on the plans. The future area will be covered by this permit. Upon development of the future area, a revised plan must be submitted. N. C. Division of Water Quality Wilmington Regional Office 127 Cardinal Drive Extension Wilmington, NC 28405 (910) 395-3900 (910) 350-2004 Fax Customer Service 1 800 623-7748 ;,�d_,«—A N DENR Mr. Jay Bundy Page 2 February 23, 2004 V/10. Please dimension the building. 11. Please provide a note on the plans that all roof drainage will be directed so as to be picked up by the pond. Please note that this request for additional information is in response to a preliminary review. The requested information should be received by this Office prior to March 1, 2004. If you need additional time to submit the information, please mail or fax your request for a time extension to the Division at the address and fax number at the bottom of this letter. The request must indicate the date by which you expect to submit the required information. The Division is allowed 90 days from the receipt of a completed application to issue the permit. The construction of any impervious surfaces, other than a construction entrance under an approved Sedimentation Erosion Control Plan, is a violation of NCGS 143-215.1 and is subject to enforcement action pursuant to NCGS 143-215.6A. Please reference the State assigned project number on all correspondence. Any original documents that need to be revised have been sent to the engineer or agent. All original documents must be returned or new originals must be provided. Copies are not acceptable. If you have any questions concerning this matter please feel free to call me at (910) 395-3900. Sincerely, Laurie Munn Environmental Engineer RSS/:Ism S:\WQS\STORMWAT\ADDINFO\2004\040215.feb04.doc cc: Laurie Munn Kimberly D. Hamby R 1,p Rap Energy 30' Dissipator ., ` A Ounlet piping + Plow Spreader Mechanism * 50' for SA Class Waters i Width as required to provide non -erosive flow VEGETATED FILTER. DETAIL Receiving I Stream 1 PLAN SECTION A -A 1 FILE MODE _ 459 MEMORY TX * * * COMMUNICATION RESULT REPORT ( FEB.23.2004 2:41PM ) * TTI OPTION ADDRESS (GROUP) RESULT ----------------------�K — -------------------------82523385552 REASON FOR ERROR E-3) NONANSWERUP R LINE FAIL P. 1 NCDENR WIRO PAGE ----P--- P.4/4 E-2) BUSY E-4) NO FACSIMILE CONNECTION State of North Carolina Department of Environment and Natural Resources Wilmington Regional Office ' Michael F. Easley, Govemor William O. Ross 7r., Secretary FAX COVER SHEET Date: A3I oq No. Of Pages: `I To: rXM From: I.&dLI-i A i &Ln n CO; CO: foul 0, FAX#: I 5a 3,3 $ 5A FAX#: 9jW50-2004 REMARK' 127 Cardillo] 0rha E.xlenebn, WIWI"% N.C. 294OW045 Telephone (910) 398,1900 Ees MO) 3504004 An Eclool Opporrunhy Aftmadva Aetbn ampanyor Hyman & Robey_,, PC Conruliing Engineers and Land Surveyors (252) 335-1888 Office (252) 338-2913 Office (252) 338-5552 Fax February 20, 2004 Ms. Laurie Munn Dept. of Environment and Natural Resources Water Quality Section 127 Cardinal Drive, Ext Wilmington, NC 28405-3845 Subject: Express Stormwater Management Permit Eastern Aluminum Storage Facility Onslow County Proj. # 040133 Dear Ms. Munn: Enclosed for your review and approval, please find the following items: 1. Two (2) copies of the above referenced plans. 2. The original and one (1) copy of the Stormwater Exemption Application and Wet Detention Basin Supplement. 3. Two (2) copies of the project description and calculations. 4. Check in the amount of $4,000.00 for the required fee. If you have any questions, please do not hesitate to call this office at (252)335-1888. cc: file Sincerely, Sean C. Robey, P.E. a Kimberly D. Hai y Engineering Assistant 150-A US Highway 158 East, Camden, NC 27921 PROJECT. DESCRIPTION Eastern Aluminum Storage Facility Onslow County - North Carolina Hunter & Bundy is proposing to construct an Eastern Aluminum Storage Facility north of Jacksonville in Onlsow County. The site is approximately 3.37 acres with frontage on Halltown Road (SR 1410) and US Highway 17. Construction on the site will include an entrance drive, one building with required parking, and a wet detention basin. An existing septic system on the site will be used. The site consists of two drainage areas. Drainage Area 1 contains 1.75 acres along the Halltown Road frontage. This drainage area will contain all of the impervious surfaces on the site. This includes 22,500 sf of building, 7,500 sf of future building addition, 20,032 sf of asphalt pavement, and 1,996 sf of concrete. The concrete areas include the loading dock and ramp, sidewalk, and dumpster pad. This creates a total impervious area of 52,028 sf (1.20 acres) or 68.57% of the drainage area. Stonnwater from the east side of the building will be collected in a grass lined swale with 3:1 side slopes that will drain to an underground collection system which also collects the runoff from the parking lot. The drainage from the west side of the building (roof) will be collected in a piped drainage system. All of the water collected from the impervious areas will drain to a wet detention basin designed for 85% TSS removal. The pond was sized based on 70% impervious using the 85% TTS removal SA/DA chart. Inflow to the pond was determined utilizing TR-55. The actual storage provided slightly exceeds the I" runoff. (The 1" storage in our pond assumes straight sides from permanent pool; therefore, additional storage is provided due to the 3:1 side slopes.) The pond discharges into a 215 if grass lined swale. Peak discharge during a 10 year storm will be 1.49 cfs and during a 25 year storm it will be 3.01 cfs. Soils on site are a Craven fine loam. This soil is in a "C" hydrology group which indicates permeability rates that would be too slow for infiltration. Based on this soil type and the water table, we feel that a wet detention basin will be the most appropriate method of stormwater treatment for this site. Drainage Area 2 contains the remaining 1.62 acres of land that will remain undeveloped. All of this land drains by sheet flow across the grassed land to existing perimeter ditches. The disturbed area required for site development is approximately 2.37 acres. The application for Erosion and Sedimentation Control is being files for 3.5 acres to allow the owner to perform some fine grading outside the area needf Id E1EJ FEB 2 3 2004 DWR PROS # TR-55 GRAPHICAL DISCHARGE METHOD VERSION 1.11 Project EASTERN ALUMINUM STORAGE User: KDH Date: 02-19-04 County ONSLOW State: NC Checked: Date: Subtitle: DRAINAGE TO DETENTION POND Data: Drainage Area 1.75 * Acres Runoff Curve Number 90 * Time of Concentration: 0.20 * Hours Rainfall Type II Pond and Swamp Area NONE I Storm Number 1 1 2 1 3 1 9 1 5 1 6 1 7 1 I----------------------I------I------I------I------I------I------I------1 Frequency (yrs) 1 2 5 1 10 1 25 1 50 1 100 1 I I I I I I I i I I 29 -Hr Rainfall ( in) 1 3.5 1 9 1 5. 5 1 6.3 1 7.1 1 8. 3 1 9. 1 1 I I I I I I I I I Ia/P Ratio 0.06 0.06 1 0.04 1 0.04 1 0.03 1 0.03 1 0.02 1 I I I I I I I I I Used 0.10 0.10 0.10 0.10 0.10 0.10 1 0.10 1 I I I I I I I I I Runoff (in) 2.45 2. 92 4.36 I 5.14 5.92 1 7.10 1 7.89 1 I I I I I I I I I I Unit Peak Discharge 11.250 11.250 11.250 11.250 11.250 11.250 11.250 1 (cfs/acre/in) I I I I I I I I I I I Pond and Swamp Factorl 1.00 1 1.00 1 1.00 1 1.00 1 1.00 1 1.00 1 1.00 1 0.0% Ponds Used I I I I I I I I ----------------------I------I------I------I------I------I------I------I Peak Discharge (cfs) 5 1 6 1 10 I 11 13 1 16 1 17 1 * - Value(s) provided from TR-55 system routines G.��-09 FE3 � ' Dwa PR�� � TR-55 CURVE NUMBER COMPUTATION VERSION 1.11 Project EASTERN ALUMINUM STORAGE User: KDH Date: 02-19-04 County ONSLOW State: NC Checked: Date: Subtitle: DRAINAGE TO DETENTION POND Subarea : 1.75 ------------------------------------------------------------------------------ Hydrologic Soil Group COVER DESCRIPTION A B C D Acres (CN) ------------------------------------------------------------------------------ FULLY DEVELOPED URBAN AREAS (Veg Estab.) Open space (Lawns,parks etc.) Good condition; grass cover > 75% - - 0.55(74) - Impervious Areas Paved parking lots, roofs, driveways - - 1.20(98) - Total Area (by Hydrologic Soil Group) 1. 75 ------------------------------------------------------------------------------- SUBAREA: 1.75 TOTAL DRAINAGE AREA: 1.75 Acres WEIGHTED CURVE NUMBER:90* ------------------------------------------------------------------------------- * - Generated for use by GRAPHIC method re TR-55 Tc and Tt THRU SUBAREA COMPUTATION VERSION 1.11 Project EASTERN ALUMINUM STORAGE User: KDH Date: 02-19-04 County ONSLOW State: NC Checked: Date: Subtitle: DRAINAGE TO DETENTION POND ----------------------------------------------------------------------------- Flow Type 2 year Length Slope Surface n Area Wp Velocity Time rain (ft) (ft/ft) code (sq/ft) (ft) (ft/sec) (hr) ------------------------------------------------------------------------------- Sheet 9 36 .0096 F 0.126 Shallow Concent'd 190 .005 U 0.046 Shallow Concent'd 235 .0138 P 0.027 Time of Concentration = 0.20* --- Sheet Flow Surface Codes --- A Smooth Surface F Grass, Dense B Fallow (No Res.) G Grass, Burmuda C Cultivated < 20 8 Res. H Woods, Light D Cultivated > 20 % Res. I Woods, Dense E Grass -Range, Short * - Generated for use by GRAPHIC method --- Shallow Concentrated --- Surface Codes P Paved U Unpaved TR-55 CURVE NUMBER COMPUTATION VERSION 1.11 Project EASTERN ALUMINUM STORAGE User: KDH Date: 02-19-04 County ONSLOW. State: NC Checked: Date: Subtitle: DRAINAGE TO DETENTION POND Subarea : 1.75 ------------------------------------------------------------------------- Hydrologic Soil Group COVER DESCRIPTION A B C D Acres (CN) ----------------------------------------------------- ---------------- FULLY DEVELOPED URBAN AREAS (Veg Estab.) Open space (Lawns, parks etc.) Good condition; grass cover > 75% - - 0.55(74). Impervious Areas _ 1.20(98) Paved parking lots, roofs, driveways - - Total Area (by Hydrologic Soil Group) 1.75 ---'--------- SUBAREA: 1.75 TOTAL DRAINAGE AREA: 1.75 Acres--- - WEIGHTED CURVE NUMBER:90 ----------------------------------------- ------ * - Generated for use by GRAPHIC method TR-55 Tc and Tt THRU SUBAREA COMPUTATION VERSION 1.11 Project EASTERN ALUMINUM STORAGE User: KDH Date: 02-19-04 County ONSLOW State: NC Checked: Date: Subtitle: DRAINAGE TO DETENTION POND . -- --------------- Flow Type 2 year rain -- --------------- Sheet 4 Shallow Concent'd Shallow Concent'd ---------------------------- Length Slope Surface n (ft) (ft/ft) code --------------------------- 36 .0096 F 190 .005 U 235 .0138 P --- Sheet Flow Surface Codes --- A Smooth Surface F Grass, Dense B Fallow (No Res.) G Grass, Burmuda C Cultivated < 20 % Res. H Woods, Light D Cultivated > 20 % Res. I Woods, Dense E Grass -Range, Short ------------------------------- Area Wp Velocity Time (sq/ft) (ft) (ft/sec) (hr) ------------------------------- 0. 126 0. 046 0. 027 Time of Concentration = 0.20* --- Shallow Concceenn --- SurfaceCar, P Pav U Un 4 ��� 18550 • •'•..VOINEEP' •.� * - Generated for use by GRAPHIC method TR-55 GRAPHICAL DISCHARGE METHOD VERSION 1.11 Project EASTERN ALUMINUM STORAGE User: KDH Date: 02-19-04 County ONSLOW State: NC Checked: Date: Subtitle: DRAINAGE TO DETENTION POND Data: Drainage Area 1.75 * Acres Runoff Curve Number 90 Time of Concentration: 0.20 * Hours Rainfall Type II Pond and Swamp Area NONE . Storm Number I 1 1 2 1 3 1 4 1 5 1 6 7 1 ----------------------I------I------I ------I------I------I------I------I I Frequency (yrs) 1 1 2 1 5 1 10 1 25 1 50 1 100 1 I I I I I I I I I I 24 -Hr Rainfall ( in) 1 3. 5 1 4 1 5. 5 1 6. 3 1 7.1 1 8. 3 1 9.1 1 I I I i I I I I I 1 Ia/P Ratio 0.06 1 0.06 1 0.04 1 0.04 1 0.03 1 0.03 1 0.02 1 I I I I I i I I I Used 1 0.10 1 0.10 1 0.10 1 0.10 1 0.10 1 0.10 1 0.10 1 I I I I I I I I I I Runoff (in) 1 2.45 1 2. 92 1 4.36 1 5.14 1 5. 92 1 7.10 1 7.89 I I I I I I I I I I 1 Unit Peak Discharge 11.250 11.250 11.250 11.250 11.250 1 1. 250 11.250 1 (cfs/acre/in). I I I I I I I I I I I Pond and Swamp Factorl 1.00 1 1.00 1 1.00 1 1.00 1 1.00 1 1.00 1 1.00 I 0.0% Ponds Used I I I I I I I I----------------------I------I------I------I------I------I------I------I I Peak Discharge (cfs) 5 1 6 1 10 1 11 1 13 1 16 1 17 1 * - Value(s) provided from TR-55 system routines "PERMANENT POOL DETENTION PONDS Hyman & Robey, PC DESIGN OF POND 150-A Hwy 158 East Camden, NC 27921 Eastern Aluminum Warehouse (252)-335-1888 10 Yr, 24 Hr Storm 02/21/04 DETENTION POND Page l SA/DA PERCENTAGES FOR 90% TSS REMOVAL WITHOUT VEGETATIVE FILTER % IMPRV 3.0 FT 3.5 FT 4.0 FT 4.5 FT 5.0 FT 5.5 FT 6.0 FT 6.5 FT 7.0 FT 10% 1.3 1.0 0.8 0.7 0.6 0.5 0.4 0.3 0.2 20% 2.4 2.0 1.8 1.7 1.5 1.4 1.2 1.0 0.9 30% 3.5 3.0 2.7 2.5 2.2 1.9 1.6 1.3 1.1 40% 4.5 4.0 3.5 3.1 2.8 2.5 2.1 1.8 ` 1.4 50% 5.6 5.0 4.3 3.9 3.5 3.1 2.7 2.3 1.9 60% 7.0 6.0 5.3 4.8 4.3 3.9 3.4 2.9 2.4 70% 8.1 7.0 6.0 5.5 5.0 4.5 3.9 3.4 2.9 80% 9.4 8.0 7.0 6.4 5.7 5.2 4.6 4.0 3.4 90% 10.7 9.0 7.9 7.2 6.5 5.9 5.2 4.6 19 100% 12.0 10.0 8.8 8.1 7.3 6.6 5.8 5.1 4.3 WATERSHED AREA: 1.7 ACRES WATERSHED % IMPERVIOUS: 70 % PERMANENT POOL ELEVATION: 39 FT DESIGN PERMANENT POOL DEPTH: 5 FT SA/DAPERCENTAGE FACTOR: 3.7 % TAKEN ROM 85% TSS REMOVAL CHART (NOT FROM W% CHART SHOWN ABOVE) POND SURFACE AREA REQ'D: FOREBAY AREA: AT WIDTH = 0.33 LENGTH, WIDTH = 30.221 LF LENGTH = 90.663 LF Use these dimensions: WIDTH LENGTH VOLUME OF 1" RAINFALL 2740 SF 822 SF (BASED UPON MINIMUM SURFACE AREA) 34.26 LF 87 LF AREA OF ROOFS: 0.69 AC AREA OF PARKING/CONCRETE: 0.46 AC AREA OF GREEN AREAS: 0.55 AC VOLUME OF RUNOFF 4490.31 CF STORAGE DEPTH FOR MINIMUM AREA = ELEVATION OF 1" RAINFALL = 40.51 Normal Pool Elevation 39 VOL (CF)=[(ROOP 1.0)+(PARKING'.95)+(GRASS-0.2)1.43.560/12 1.51 FT 18550 d', �VII�EG� i...NC. no .. DRAWDOWN - WATER QUALITY Q(2 DAYS) = 0.02599 CFS Q(5 DAYS) = 0.01039 CFS l" RUNOFF STAGE 1.51 FT DEPTH OF DRAWDOWN DEVICE BELOW OUTLET 1.5 FT 1" RUNOFF OUTLET DEVICE: 0.89335 INCH DIA HOLE DIAMETER OF HOLE TO USE: 1 INCH DIAMETER 1" STORM RUNOFF DRAWDOWN TIME 2.28019 DAYS INFLOW HYDROGRAPH Return Year Storm 10 Yr Qp = Peak Discharge = I cfs Tc = Time of Concentration = A = [Q/(Cd* SQRT(2gh))] * 144 Rad. = SQRT(A/PI) Dia. =2*Rad. 12 min Calculation of Tp (Time to Peak) From SCS NEH 4 , page 15-7 Eqn. 15.4 Lag Time (L) = (1" 0.8*(S+1)"0.7)/(1900*Y"0.5) for L in Hrs where: I = hydraulic length of watershed (ft) S = (1000/CN)-10 CN = approximately same CN from TR-55 Y = avg. watershed land slope in % S = (1000/CN)-10 = 1.11111 L= 0.12127 hrs From SCS NEH 4 , page 16-7 Eqn. 16.7 Tp=D/2+L where : D = unit of excess duration rainfall (hrs) L = Lag Time (hrs) From SCS NEH 4 , page 16-8 Eqn. 16.12 D = 0.133 tc where: Tc = Time of Concentration (hrs) - (See Tr-55 Printout) THEREFORE: D = 0,0266 hrs Tp = 0.13457 hrs = 8.07417 min Volume under Hydrograph = 1.39 * Qp * Tp = 7407.25 Cubic Feet 461 1.11111 90 0.98 SEAL 18550 HtC I tppe�i\\\\\�. Inflow Hydrograph SCS Dimensionless Hydrograph Time Discharge Time Discharge Volume Ratio Ratio hr cfs cf 0.00 0.00 0.00 0 0.10 0.03 0.01 0 16 0.20 0.10 0.03 1 53 0.30 0.19 0.04 2 101 0.40 0.31 0.05 3 165 0.50 0.47 0.07 5 250 0.60 0.66 0.08 7 352 0.70 0.82 0.09 9 437 0.80 0.93 0.11 10 496 0.90 0.99 0.12 11 528 1.00 1.00 0.13 11 533 1.10 0.99 0.15 it 528 1.20 0.93 0.16 10 496 1.30 0.86 0.17 9 458 1.40 0.78 0.19 9 416 1.50 0.68 0.20 7 362 1.60 0.56 0.22 6 298 1.70 0.46 0.23 5 245 1.80 0.39 0.24 4 208 1.90 0.33 0.26 4 176 2.00 0.28 0.27 3 149 2.20 0.21 0.30 2 221 2.40 0.15 0.32 2 157 2.60 0.11 0.35 1 114 2.80 0.08 0.38 1 82 3.00 0.06 0.40 1 59 3.20 0.04 0.43 0 43 3.40 0.03 0.46 0 31 3.60 0.02 0.48 0 22 3.80 0.02 0.51 0 16 4.00 0.01 0.54 0 12 4.50 0.01 0.61 0 13 5.00 0.00 0.67 0 0 Volume under hydrograph = 7036 cf Based upon runoff volume = 7407.25 cf Depth req'd for minimum area = 2.48514 18550 '�::::�-� FAN C. ko..'O STAGE STORAGE FUNCTION OF POND (FOR RECTANGULER DETENTION POND ONLY) Minimum surface area taken at normal water level BASIN AREA INCR ACCUM VOLUME VOLUME STAGE In s S Z sf cf cf ft Pond Side Slope (M) = In Z Z est Elevation 2981 0 0 0 Surface area at normal pool 39 3353 1584 1584 0.5 7.37 -0.69 0.51 39.5 3744 1774 3358 1 8.12 0.00 0.98 40 4153 1974 5332 1.5 8.58 0.41 1.46 40.5 4580 2183 7515 2 8.92 0.69 1.97 41 5025 2401 9916 2.5 9.20 0.92 2.50 41.5 5487 2628 12544 3 9.44 1.10 3.07 42 5968 2864 15408 3.5 9.64 1.25 3.66 42.5 6467 3109 18517 4 9.83 1.39 4.30 43 6984 3363 21880 4.5 9.99 1.50 4.97 43.5 7518 3626 25505 5 10.15 1.61 5.68 44 Regression Output: Constant 9.34346 Ks = S/Z'b = 3450.398 Sul Err of Y Est 0.00969 R Squared 0.99962 No. of Observations 7 Degrees of Freedom 5 X Coefficient(s) 1.15215 = b Std Err of Coef. 0.01009 FOR VERTICAL SIDED DETENTION POND SET b=0, AND Ks = SURFACE AREA (SF) STAGE DISCHARGE (FOR RISER/BARRELL SPILLWAY W EMERGENCY WEIR) RISER Dr = 18 Riser Dia. (in) Etop = 40.51 Elev. Top Riser (ft) Cwr = 3.33 Riser weir coeff Cdr = 0.60 Riser orifice coeff Hln = 5 Number of Holes Hid = 3 Hole Dia. (in) EHI = 60.00 Elev. Holes (1) H2n = 5 Number of Holes H2d = 2 Hole Dia. (in) EH2 = 60.00 Elev. Holes (2) H3n = 0 Number of Holes H3d = 2 Hole Dia. (in) EH3 = 60.00 Elev. Holes (3) BARREL: Db = 12 Barrel Dia. (in) Einv = 39.00 Elev Invert Barrel (ft) Cdb = 0.60 Barrel orifice coeff 41.49 Page 4 3 SEAL 18550 '• "'4yIIVG� ,.FAN C. 10� Bartell Adjustment Factor EMERGENCY WEIR Page 5 Cw = 3 Weir coeff Ecr = 60.00 Elev weir coeff (ft) Lw = 20 Weir Length (ft) Riser Riser Riser Elevation Hole Hole Hole Riser Riser Barrel Principal Emergcy (1) (2) (3) (weir) (orifice) Spillway Weir 39.00 0.0 0.0 0.0 0.0 0.0 0.0 0.00 0.0 39.00 0.0 0.0 0.0 0.0 0.0 0.0 0.00 0.0 39.01 0.0 0.0 0.0 0.0 0.0 0.0 0.00 0.0 39.03 0.0 0.0 0.0 0.0 0.0 0.0 0.00 0.0 39.07 0.0 0.0 0.0 0.0 0.0 0.1 0.00 0.0 39.13 0.0 0.0 0.0 0.0 0.0 0.1 0.00 0.0 39.21 0.0 0.0 0.0 0.0 0.0 0.3 0.00 0.0 39.32 0.0 0.0 0.0 0.0 0.0 0.5 0.00 0.0 39.45 0.0 0.0 0.0 0.0 0.0 0.8 0.00 0.0 39.59 0.0 0.0 0.0 0.0 0.0 1.2 0.00 0.0 39.73 0.0 0.0 0.0 0.0 0.0 1.7 0.00 0.0 39.87 0.0 0.0 0.0 0.0 0.0 2.2 0.00 0.0 40.00 0.0 0.0 0.0 0.0 0.0 2.7 0.00 0.0 40.13 0.0 0.0 0.0 0.0 0.0 3.0 0.00 0.0 40.24 0.0 0.0 0.0 0.0 0.0 3.2 0.00 0.0 40.34 0.0 0.0 0.0 0.0 0.0 3.5 0.00 0.0 40.43 0.0 0.0 0.0 0.0 0.0 3.6 0.00 0.0 40.50 0.0 0.0 0.0 0.0 0.0 3.8 0.00 0.0 40.55 0.0 0.0 0.0 0.1 1.8 3.9 0.14 0.0 40.60 0.0 0.0 0.0 0.4 2.6 4.0 0.43 0.0 40.64 0.0 0.0 0.0 0.7 3.0 4.0 0.71 0.0 40.69 0.0 0.0 0.0 1.2 3.6 4.1 1.21 0.0 40.71 0.0 0.0 0.0 1.5 3.9 4.2 1.45 0.0 40.72 0.0 0.0 0.0 1.5 3.9 4.2 1.49 0.0 40.71 0.0 0.0 0.0 1.4 3.8 4.2 1.42 0.0 40.70 0.0 0.0 0.0 1.3 3.7 4.1 1.28 0.0 40.68 0.0 0.0 0.0 1.1 3.5 4.1 1.13 0.0 40.67 0.0 0.0 0.0 1.0 3.4 4.1 0.98 0.0 40.65 0.0 0.0 0.0 0.8 3.2 4.1 0.85 0.0 40.64 0.0 0.0 0.0 0.7 3.1 4.0 0.73 0.0 C R0, 40.63 0.0 0.0 0.0 0.6 2.9 4.0 0.62 0.0 Fessio QP H A 40.60 0.0 0.0 0.0 0.4 2.5 4.0 0.41 0.0 ! ati e %� SEAL 40.58 0.0 0.0 0.0 0.3 2.2 3.9 0.28 0.0 a ssso sF�N C. •ROg�i 0 Page 6 ROUTING OF INFLOW HYDROGRAPH THROUGH POND AND OUTFLOW DEVICE Total Riser Riser Riser Barrel Emerg Time Inflow Storage Stage Outflow Holes (weir) (orifice) Spillway t (hr) cfs cf Elevation cfs (1+2+3) cfs cfs cfs cfs cfs 0.000 0 0 39.00 0.00 0.00 0.00 6.00 0.00 0.00 0.013 0 0 39.00 0.00 0.00 0.00 0.00 0.00 0.00 0.027 1 15.9869 39.01 0.00 0.00 0.00 0.00 0.00 0.00 0.040 2 69.2764 39.03 0.00 0.00 0.00 0.00 0.02 0.00 0.054 3 170.527 39.07 0.00 0.00 0.00 0.00 0.05 0.00 0.067 5 335.724 39.13 0.00 0.00 0.00 0.00 0.13 0.00 0.081 7 586.185 39.21 0.00 0.00 0.00 0.00 0.27 0.00 0.094 9 937.896 39.32 0.00 0.00 0.00 0.00 0.49 0.00 0.108 10 1374.87 39.45 0.00 0.00 0.00 0.00 0.81 0.00 0.121 11 1870.46 39.59 0.00 0.00 0.00 0.00 1.21 0.00 0.135 11 2398.03 39.73 0.00 0.00 0.00 0.00 1.67 0.00 0.148 11 2930.93 39.87 0.00 0.00 0.00 0.00 2.17 0.00 0.161 10 3458.49 40.00 0.00 0.00 0.00 0.00 2.68 0.00 0.175 9 3954.08 40.13 0.00 0.00 0.00 0.00 2.99 0.00 0.188 9 4412.37 40.24 0.00 0.00 0.00 0.00 3.24 0.00 0.202 7 4828.03 40.34 0.00 0.00 0.00 0.00 3.46 0.00 0.215 6 5190.4 40.43 0.00 0.00 0.00 0.00 3.63 0.00 0.229 5 5488.82 40.50 0.00 0.00 0.00 0.00 3.77 0.00 0.242 4 5733.96 40.55 0.14 0.00 0.14 1.79 3.88 0.00 0.256 4 5934.76 40.60 0.43 0.00 0.43 2.57 3.96 0.00 0.269 3 6089.7 40.64 0.71 0.00 0.71 3.04 4.03 0.00 0.296 2 6319.01 40.69 1.21 0.00 1.21 3.62 4.12 0.00 0.323 2 6422.8 40.71 1.45 0.00 1.45 3.85 4.16 0.00 0.350 1 6438.53 40.72 1.49 0.00 1.49 3.88 4.17 0.00 0.377 1 6407.85 40.71 1.42 0.00 1.42 3.82 4.16 0.00 0.404 1 6352.54 40.70 1.28 0.00 1.28 3.69 4.13 0.00 0.431 0 6286.7 40.68 1.13 0.00 1.13 3.54 4.11 0.00 0.458 0 6219.7 40.67 0.98 0.00 0.98 3.38 4.08 0.00 0.484 0 6155.43 40.65 0.85 0.00 0.85 3.21 4.05 0.00 0.511 0 6095.86 40.64 0.73 0.00 0.73 3.05 4.03 0.00 0.538 0 6041.56 40.63 0.62 0.00 0.62 2.90 4.01 0.00 0.606 0 5920.46 40.60 0.41 0.00 0.41 2.52 3.96 0.00 0.673 0 5834.9 40.58 0.28 0.00 0.28 2.21 3.92 0.00 40.7185 = maximum stage elevation 1.49363 = maximum discharge // Aq0�y 1'/ y,-" SEAL J 18550 _ -04* INRog��. �4j��mmllutt�o��• Eastern Aluminum Onslow County 10 yr STORM 12 m 10 r s d m--- INFLOW (cfs) . g u +� y �...-OUTFLOW (cfs) 2 p^r�d 7au�y '� fir• i� i ✓""R! x •r:pU� w 0.000 0.200 0.400 0.600 0.800 Time (hrs) 'o SEAL 2 = I8550 c VG me, ,,//'////J�411 CII11kpe0\\\\\\\\