The URL can be used to link to this page

Home My WebLink AboutSW7101206_CURRENT PERMIT_20201006STORMWATER DIVISION CODING SHEET POST -CONSTRUCTION PERMITS PERMIT NO. DOC TYPE ZPCURRENT PERMIT APPROVED PLANS ❑ HISTORICAL FILE ❑ COMPLIANCE EVALUATION INSPECTION DOC DATE YYYYMMDD ROY COOPER Governor' MICHAEL S. REGAN So, crerory BRIAN WRENN Acting Vita tor NORTH CAROLINA Environmental Quality October 6, 2020 Commerce Pond Owners Association, Inc. Attention: Mr. John W. Taylor, Vice President P.O. Box12006 New Bern, NC 28561 Subject: Stormwater Permit No. SW7101206 Renewal Commerce Park II High Density Project Craven County Dear Mr. Taylor: The Washington Regional Office received a Stormwater Management Permit Application for renewal of the subject permit on September 14, 2020. Staff review of the applications have determined that the permit can be reissued. We are forwarding Permit No. SW7101206 dated October 6, 2020, for the continued operation of the subject project. This permit, upon its effective date, will replace all previous State Stormwater permits for this project. This permit shall be effective from January 12, 2021 until January 11, 2029 and shall be subject to the conditions and limitations as specified therein, and does not supercede any other agency permit that may be required. Please pay special attention to the Operation and Maintenance requirements in this permit. Failure to establish an adequate system for operation and maintenance of the stormwater management system will result in future compliance problems. If any parts, requirements, or limitations contained in this permit are unacceptable, you have the right to request an adjudicatory hearing upon written request within thirty (30) days following receipt of this permit. This request must be in the form of a written petition, conforming to Chapter 150B of the North Carolina General Statutes, and filed with the Office of Administrative Hearings, 6714 Mail Service Center, Raleigh, NC 27699-6714. Unless such demands are made this permit shall be final and binding. If you have any questions, or need additional information concerning this matter, please contact me at (252) 948-3923. Sincerely, ;';�•�� is �'�-,7� Roger K. Thorpe Environmental Engineer North Carolina Department of Environinental Quality . Division of Energv. Mineral and Land Resom'ces J/ Washlnyton Regional Office 043 Washington Square Mall I Washington. North Carolina 3788o STATE OF NORTH CAROLINA DEPARTMENT OF ENVIRONMENTAL QUALITY DIVISION OF ENERGY, MINERAL, AND LAND RESOURCES 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 Commerce Pond Owners Association, Inc. Commerce Park 11 Located at 1315 Commerce Drive, New Bern, NC, Craven 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 Energy, Mineral, and Land Resources (Division) and considered a part of this permit. This permit shall be effective from January 12, 2021 until January 11, 2029, 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. This stormwater system has been approved for the management of stormwater runoff as described in Section 1.6 of this permit. The subdivision is permitted for lots, each allowed a maximum of (see attached table) square feet of built -upon area and 15,500 square feet of existing off -site built -upon area. The runoff from all built -upon area within the permitted drainage area of this project must be directed into the permitted stormwater control system. 4. Each new lot owner within the subdivision must submit two (2) copies of the final proposed development plans to the Division of Energy, Mineral, and Land Resources and receive written plan approval prior to any construction on the lot to ensure compliance with this State Stormwater Management Permit. The built -upon areas associated with this project shall be located at least 50 feet landward of all perennial and intermittent surface waters. The following design elements have been permitted for this wet detention pond stormwater facility, and must be provided in the system at all times. a. Drainage Area, acres: b. Total Impervious Surfaces, ft2 Average Pond Design Depth, feet TSS removal efficiency: Design Storm: Permanent Pool Elevation, FMSL: Permitted Surface Area @PP, ft2: Permitted Storage Volume, ft3: Storage Elevation, FMSL: Predevelopment 1 year 24 hour: Post development 1 year 24 hour: Controlling Orifice: Permanent Pool Volume, ft3: Forebay Volume, ft3: Maximum Fountain Horsepower: Receiving Stream / River Basin: Stream Index Number: Classification of Water Body: II. SCHEDULE OF COMPLIANCE 4.46 (including 21,800sf of off -site area) 128,275 new + (5,434sf vested + 15,500sf off -site) 5.00 90% 1.50 17.00 8,850 23,225 at temporary pool 19.00 4.15 cfs 2.89 cfs 1.25" O pipe 34,486 6,478 1/8hp / 0.125hp Wilson Creek / Neuse River 27-101-37 "C; Sw, NSW" No homeowner/lot owner/developer shall fill in, alter, or pipe any drainage feature (such as swales) shown on the approved plans as part of the stormwater management system without submitting a revision to the permit and receiving approval from the Division. The permittee is responsible for verifying that the proposed built -upon area for the entire lot does not exceed the maximum allowed by this permit. Once the lot transfer is complete, the built -upon area may not be revised without approval from the Division, and responsibility for meeting the built -upon area limit is transferred to the individual property owner. If an Architectural Review Board or Committee is set up by the permittee to review plans for compliance with the BUA limit, the plans reviewed must include all proposed built -upon area. Any approvals given by the Board do not relieve the homeowner of the responsibility to maintain compliance with the permitted BUA limit. 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 permittee 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. 5. 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. 6. The permittee 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: a. Any revision to the approved plans, regardless of size. b. Project name change. C. Transfer of ownership. d. Redesign or addition to the approved amount of built -upon area. e. 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. 7. The permittee shall submit for approval, final site layout and grading plans for any permitted future development areas shown on the approved plans, prior to construction. 3. 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. 3. During construction, erosion shall be kept to a minimum and any eroded areas of the system will be repaired immediately. 10. 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 these deviations. 11. 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. 12. The permittee shall at all times provide the operation and maintenance necessary to assure that all components of the permitted stormwater system function 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 re -vegetation of side slopes. d. Immediate repair of eroded areas. e. Maintenance of side slopes in accordance with approved plans. f. Debris removal and unclogging of structures, orifice, catch basins and piping. g. Access to all components of the system must be available at all times. 13. Records of maintenance activities must be kept by the permittee. The records will indicate the date, activity, name of person performing the work and what actions were taken. 14. This permit shall become void unless the facilities are constructed in accordance with the conditions of this permit, the approved plans and specifications, and other supporting data. 15. Prior to the sale of any lot, the following deed restrictions must be recorded: a. The following covenants are intended to ensure ongoing compliance with State Stormwater Management Permit Number SW7101206, as issued by the Division under NCAC 2H.1000. b. The State of North Carolina is made a beneficiary of these covenants to the extent necessary to maintain compliance with the Stormwater Management Permit. C. These covenants are to run with the land and be binding on all persons and parties claiming under them. d. The covenants pertaining to stormwater may not be altered or rescinded without the express written consent of the State of North Carolina, Division of Energy, Mineral, and Land Resources. e. Alteration of the drainage as shown on the approved plans may not take place without the concurrence of the Division. The maximum built -upon area per lot is as listed below Lot # Lot Area (sf) Maximum BUA (sf) BUA (%) 1 24,577 0 0 2 20,108 18,097 90 3 20,134 18,121 90 4 20,160 18,144 90 5 20,185 18,167 90 6 20,211 16,775 83 7 20,237 16,797 83 8 26,717 22,175 83 This allotted amount includes any built -upon area constructed within the lot property boundaries, and that portion of the right-of-way between the front lot line and the edge of the pavement. Built upon area includes, but is not limited to, structures, asphalt, concrete, gravel, brick, stone, slate, coquina and parking areas, but does not include raised, open wood decking, or the water surface of swimming pools. 3. All runoff on the lot must drain into the permitted system. This may be accomplished through providing roof drain gutters, which drain to the street, grading the lot to drain toward the street, or grading perimeter swales and directing them into the pond or street. Lots that will naturally drain into the system are not required to provide these measures. h. Built -upon area in excess of the permitted amount will require a permit modification. i. The owners of lots 2-8 must submit two (2) copies of final proposed development plans to the Division and receive written plan approval to ensure compliance with State Stormwater Management Permit Number SW7101206 prior to any construction on the lot. j. The project and each lot will maintain a 50 foot wide vegetated buffer between all impervious areas and surface waters. k. Each lot owner within Commerce Park II is by ownership a member of the Commerce Pond Owner's Association, Inc. and subject to the conditions and requirements of the Stormwater Management Permit SW7101206. 16. A copy of the recorded deed restrictions must be submitted to the Division within 30 days of the date of recording the plat, and prior to selling lots. The recorded copy must contain all of the statements above, the signature of the Permittee, the deed book number and page, and the stamp/signature of the Register of Deeds. 17. Prior to transfer of the permit, the stormwater facilities will be inspected by the Division personnel. The facility must be in compliance with all permit conditions. Any items not in compliance must be repaired or replaced to design condition prior to the transfer. Records of maintenance activities performed to date will be required. 18. Decorative spray fountains will be allowed in the stormwater treatment system, subject to the following criteria: a. The fountain must draw 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 1/8hp (0.125hp). 19. If permeable pavement credit is desired, the permittee must submit a request to modify the permit to incorporate such language as required by the Division. The request to modify must include a soils report identifying the type of soil, the Seasonal High Water Table elevation and the infiltration rate. Upon the successful completion of a permit modification, the individual lot owners that request to utilize permeable pavements must submit the necessary forms and documentation to the permittee and receive approval prior to construction of the permeable pavement. 20. A copy of the approved plans and specifications shall be maintained on file by the Permittee at all times. III. GENERAL CONDITIONS 1. 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 completed Name/Ownership Change form signed by both parties, to the Division, accompanied by the supporting documentation as listed on page 2 of the form. The approval of this request will be considered on its merits and may or may not be approved. 2. The permittee is responsible for compliance with all permit conditions until such time as the Division approves a request to transfer the permit. 3. Failure to abide by the conditions and limitations contained in this permit may subject the Permittee to enforcement action by the Division, in accordance with North Carolina General Statute 143-215.6A to 143-215.6C. 4. 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) having jurisdiction. 5. 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. 6. The permittee grants DEQ Staff permission to enter the property during normal business hours for the purpose of inspecting all components of the permitted stormwater management facility. 7. The permit issued shall continue in force and effect until revoked or terminated. The permit may be modified, revoked and reissued or terminated for cause. The filing of a request for a permit modification, revocation and re -issuance or termination does not stay any permit condition. 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. 10. The issuance of this permit does not prohibit the Director from reopening and modifying the permit, revoking and reissuing the permit, or terminating the permit as allowed by the laws, rules and regulations contained in Title 15A NCAC 2H.1000, and NCGS 143-215.1 et.al. 11. The permittee shall notify the Division in writing of any name, ownership or mailing address changes at least 30 days prior to making such changes. 12. This permit shall be effective from the date of issuance until January 11, 2029. Application for permit renewal shall be submitted 180 days prior to the expiration date of this permit and must be accompanied by the processing fee. Permit issued this the 6th day of October 2020. NORTH CAROLINA ENVIRONMENTAL MANAGEMENT COMMISSION For Brian Wrenn, Director Division of Energy, Mineral and Land Resources By Authority of the Environmental Management Commission Permit Number SW7101206 `... a.. �, �,.. ,r .. ., nr'"_^^�'„ y:-UEM` :Ub `.UNL'Y ..a+�' `yw U 1 , i, 7 , ,.u......., . ,..,... ._ V Date Received Fee Paid Permit Number 14/)-c S 5 iC4 NC DEQ Division of Energy, Mineral and Land Resources STATE STORMWATER: PERMIT RENEWAL APPLICATION FORM In accordance with 15A__NCAC_2H_1045(3), the current permit holder shall renew their high density permit 180 days prior to its expiration. Renewed permits are valid for a period of 8 years per Session Law 2011-398 (SB 781) Section 60. (c). This application form is for permit renewals only. A. PROJECT INFORMATION f, 1. State Stormwater Permit Number: S vvq i b j a01, 2. Project name: _ 3. Project street address: 13.15 `\:Oyw rnPY C� llr . City: "LyLm County: (\)C ZIP. to 4. What, if any, changes have been made to the project as permitted? NCIV C- If the project has changed from the original approved plans, please complete SWU-101 for a Major Modification or Minor Modification Application form available at: https//deq,nc_gov/about/divisions/energy_. .............. mineral-land_resources/energy_minere l-land-rules/stormwater-program/post-construction. PERMITTEE INFORMATION If changes to the permittee or project name have been made, please complete either the Permit Update form or the Permit Transfer form available at: https://deg.nc.gov/about/divisions/energy-mineral-land- resources/energy-mineral-land-rules/stormwater-program/post-construction. State Stormwater Permits do not automatically transfer with the sale of the property. n 1. Current Permit Holder's Company Name/Organization: `—MmW"L2 VDnk NoAets K%-oG uJ im ,)�r 2. Signing Official's Name: 3. Signing Official's Title: V I C,e� Vr¢SidZ jX 4. Mailing Address: � r) ,, City: 1� 6RM State: iJC ZIP : 'Ma I 5. Street Address: 13, .A City: NQto �enti State: ZIP f 6. Phone: (ZML) b�-J!ZAUO Email: r-N% RECEIVED StN 14 2M Stormwater Permit Renewal Form Page 1 of 3 May 11, 2018 C. SUBMITTAL REQUIREMENTS Submit the application package to the appropriate DEMLR Regional Office (Coastal, SA Waters) or DEMLR Central Office (Urbanizing Areas Ph 2, USMP, Non -Coastal HQW/ORW). Only applications packages that include all required items listed below will be accepted and reviewed. Initial each item below to indicate that the required information is provided in the application package: 1. A permit application processing fee of $505.00 payable to NCDEQ. 2. One original signed hard copy and one electronic copy of this completed form. The signing official named on this application to represent the current permittee must meet one of the following: a. Corporation — a principle executive officer of at least the level of vice-president, b. Limited Liability Company (LLC) — a manager or company official as those terms are defined in G.S. 57D "North Carolina Limited Liability Company Act;" c. Public Entity — a principal executive officer, ranking official, or other duly authorized employee, d. Partnership or limited partnership — the general partner; e. Sole proprietor; or f. Letter of authorization signed by one of the signatories noted in a — e above authorizing the signature of another entity. 'vi n 3. One hard copy and one electronic copy of recorded documents required by the original permit that have not yet been received by DEMLR, including: deed restrictions, protective covenants, condominium/planned community declaration and easements. If the project has been built, include documentation that the maximum BUA per lot or maximum total BUA has not been exceeded. If the project has not been built, include a signed agreement that the final recorded deed restrictions and protective covenants will be submitted at a later date. 4. O&M Agreements, Please select one: LvU I have a copy of the current recorded O&M Agreement for all SCMs, and I will continue to keep this on file with the permit, or ❑ I do not have a copy of the current recorded O&M Agreement for all SCMs and am requesting a copy be sent to me. I agree to keep this on file with the permit. 5. Desigger Certifications, Please select one: 12 A copy of the certification(s) confirming that the project was built in accordance with the approved plans have been previously provided to the Division, or ❑ A copy of the certification(s) confirming that the project was built in accordance with the approved plans are enclosed; or ❑ The project has not yet been built. 01A 6. [IF APPLICABLE] If the project has been built, one original hard copy and one electronic copy of a signed, sealed, and dated letter from a licensed professional stating that the SCMs have been inspected, and that they have been built and maintained in accordance with the permit. N� 7. [IF APPLICABLE] When the permittee is a corporation or a limited liability corporation (LLC): Provide one hard copy and one electronic copy of documentation from the NC Secretary of State, or other official documentation, which supports the titles and positions held by the persons listed in Section C.2 per 15A NCAC 2H. 1043(3)(b). https://www.sosnc.gov/online_services/search/by_title/ Business_ Registration_ Stormwater Permit Renewal Application Form Page 2 of 3 May 11, 2018 D. PERMITTEE'S CERTIFICATION lot- the person legally responsible for the permit, certify that I have a copy of the Permit and O&M Agreement on site (or I will obtain a copy and it will be kept on site), that I am responsible for the performance of the maintenance procedures, and the site has been and will be maintained according to the O&M Agreement and approved plans. I agree to notify DEMLR of any problems with the SCMs or built -upon area and to submit the proper forms to modify or transfer the permit prior to any changes to the project, SCMs or ownership. All information provided on this permit renewal application is, to the best of my knowledge, Arr ct and conyglete. n Signature: U / V V 111_L. _ Date: clJ I �JI U" U NOTARIZATION : �( (? I Y. O^`1 (1S t� a Notary Public for the State of UV\�C County of \ �av�-►.i do hereby certify that c O personally appeared before me this the 1 Olh da 20 a 0 , and acknowledge the due execution of the forgoing instrument. Witness my hand and official seal, (Notary Seal) Notary Signature: a+,CiTAF?b,.. My commission expires-'�-'a� kG �. z ;r Stormwater Permit Renewal Application Form Page 3 of 3 May 11, 2018 Commerce Pond Owners Association, Inc. P 0 Box 12006 New Bern, NC 28561 252-633-5106 September 10, 2020 Roger Thorpe NCDEQ 943 Washington Square Mall Washington, NC 27889 Re: Stormwater Permit #SW7101206 Roger, usczVv) SEP 14 D9 We spoke on Tuesday, Sept. 8 about our stormwater permit renewal. 1 have attached a signed Permit Renewal Application Form and the check for $505 made out to NCDEQ, and have emailed a copy of the Permit Renewal Application Form also to you at roger.thorpe@ncdenc.gov. When we spoke you said that you were confident that you already had all of the initial documents that were necessary, and that all you would need is the signed Renewal Application and the payment. If you find out that you need further documentation, please call me. Thank you. Sincerely, Cindy Gaski�Ts' Office Manager State Stormwater Management Systems Permit No. SW7101206 Stormwater Improvements to Commerce Park II Stormwater Permit No. SW7101206 Craven County Designer's Certification Page 1 of 2 67. ocK as a duly registered P^v oss o �fi ;aod'in the State of North Carolina, having been authorized to observe eriodicall eekly/full time) the construction of the project, for — AU ��2 (Project Owner) hereby state that, to the best of my abiliti s, due dare 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 a part of this Certification. Noted deviations from approved plans and specispecifications:r1 * 8 sr 6 �irry � ,a' /Yl T 9,; li o 4-. c ^i l`( 10� . 111111/, GAR i, Signature —"e �QgEp� -7 _ Registration Nu ber Q 'h Date j .FN �cF •' �: SEAL RECEIVE® DEC 1 3 2011 ®WQ-WAR® Page 8 of 9 to - /fit' [•' - _ II, i State Stormwater Management Systems Permit No. SW7101206 Certification Requirements: Page 2 of 2 ✓ 1. The drainage area to the system contains approximately the permitted acreage. ✓ 2. The drainage area to the system contains no more than the penpitted amount of built -upon area. b o I+- o,, I-. ✓ 3. All the built -upon area associated with the project is graded suc i that the runoff drains to the system. S" h d �; s?dti .v.f I.", I� ow-F ✓ 4. All roof d ains are locate9gG[uch that thp}runoff is directed into the system. i s»�6514 :S9f VJ /mod �41 I rC7 L 1 ✓ 5. The outlet/bypass structure elevations are per the approved plan. ✓6. The outlet structure is located per the approved plans. ✓7. Trash rack is provided on the outlet/bypass structure. ✓�S.�All slopes are grassed with permanent vegetation. 99 Vegetated slopes are no steeper than 3:1. ✓ 10. The inlets are located per the approved plans and do not cause short- circuiting of the system. ✓ 11. The permitted amounts of surface area and/or volume have been provided. ✓ 12. Required drawdown devices are correctly sized per the approved plans. 13. All required design depths are provided. 14. All required parts of the system are provided, such as a vegetated shelf, a forebay, and the vegetated filter. 15. The required dimensions of the system are provided, per the approved plan. cc: NCDENR-DWQ Regional Office New Bern City Planning / Building Inspections Page 9 of 9 EXPRESS DEC 28 2010 permit Number: ^ ®C�(to be provided by DIVQ) NC 66 R Drainage Area Number: I Wet Detention Basin Operation and Maintenance Agreement I will keep a maintenance record on this BMP. This maintenance record will be kept in a log in a known set location. Any deficient BMP elements noted in the inspection will be corrected, repaired or replaced immediately. These deficiencies can affect the integrity of structures, safety of the public, and the removal efficiency of the BMP. The wet detention basin system is defined as the wet detention basin, pretreatment including forebays and the vegetated filter if one is provided. This system (check one): ❑ does ® does not incorporate a vegetated filter at the outlet. This system (check one): ❑ does ® does not incorporate pretreatment other than a forebay. Important maintenance procedures: — Immediately after the wet detention basin is established, the plants on the vegetated shelf and perimeter of the basin should be watered twice weekly if needed, until the plants become established (commonly six weeks). — No portion of the wet detention pond should be fertilized after the first initial fertilization that is required to establish the plants on the vegetated shelf. — Stable groundcover should be maintained in the drainage area to reduce the sediment load to the wet detention basin. — If the basin must be drained for an emergency or to perform maintenance, the flushing of sediment through the emergency drain should be minimized to the maximum extent practical. — Once a year, a dam safety expert should inspect the embankment. After the wet detention pond is established, it should be inspected once a month and within 24 hours after every storm event greater than 1.0 inches (or 1.5 inches if in a Coastal County). Records of operation and maintenance should be kept in a known set location and must be available upon request. Inspection activities shall be performed as follows. Any problems that are found shall be repaired immediately. BMP element: Potentialproblem: How I will remediate theproblem: The entire BMP Trash debris is present. Remove the trash debris. The perimeter of the wet Areas of bare soil and/or Regrade the soil if necessary to detention basin erosive gullies have formed. remove the gully, and then plant a ground cover and water until it is established. Provide lime and a one-time fertilizer application. Vegetation is too short or too Maintain vegetation at a height of long. approximatelysixinches. Form SW401-Wet Detention Basin O&M-Rev.4 Page I of ,0 Permit Number: (m be provided by DWQ) Drainage Area Number: BMP element: Potentialproblem: How I will remediate theproblem: The inlet device: pipe or The pipe is clogged. Unclog the pipe. Dispose of the swale sediment off -site. The pipe is cracked or Replace the pipe. otherwise damaged. Erosion is occurring in the Regrade the swale if necessary to Swale. smooth it over and provide erosion control devices such as reinforced turf matting or riprap to avoid future problems with erosion. The forebay Sediment has accumulated to Search for the source of the a depth greater than the sediment and remedy the problem if original design depth for possible. Remove the sediment and sediment storage. dispose of it in a location where it will not cause impacts to streams or the BMP. Erosion has occurred. Provide additional erosion protection such as reinforced turf matting or riprap if needed to prevent future erosion problems. Weeds are present. Remove the weeds, preferably by hand. If pesticide is used, wipe it on the plants rather than spraying. The vegetated shelf Best professional practices Prune according to best professional show that pruning is needed practices to maintain optimal plant health. Plants are dead, diseased or Determine the source of the dying. problem: soils, hydrology, disease, etc. Remedy the problem and replace plants. Provide a one-time fertilizer application to establish the ground cover if a soil test indicates it is necessary. Weeds are present. Remove the weeds, preferably by hand. If pesticide is used, wipe it on the plants rather than spraying. The main treatment area Sediment has accumulated to Search for the source of the a depth greater than the sediment and remedy the problem if original design sediment possible. Remove the sediment and storage depth. dispose of it in a location where it will not cause impacts to streams or the BMP. Algal growth covers over Consult a professional to remove 50 % of the area. and control the algal growth. Cattails, phragmites or other Remove the plants by wiping them invasive plants cover 507. of with pesticide (do not spray). the basin surface. Farm SW401-Wet Detention Basin O&M-Rev.4 Page 2 of 4 of Permit Number: (to be provided by D111Q) Drainage Area Number: BMP element: Potentialproblem: How I will remediate theproblem: The embankment Shrubs have started to grow Remove shrubs immediately. on the embankment. Evidence of muskrat or Use traps to remove muskrats and beaver activity is present. consult a professional to remove beavers. A tree has started to grow on Consult a dam safety specialist to the embankment. remove the tree. An annual inspection by an Make all needed repairs. appropriate professional shows that the embankment needs repair. if applicable) The outlet device Clogging has occurred. Clean out the outlet device. Dispose of the sediment off -site. The outlet device is damaged 1 Repair or replace the outlet device. The receiving water Erosion or other signs of Contact the local NC Division of damage have occurred at the Water Quality Regional Office, or outlet. the 401 Oversight Unit at 919-733- 1786. The measuring device used to determine the sediment elevation shall be such that it will give an accurate depth reading and not readily penetrate into accumulated sediments. When the permanent pool depth reads 66:5 feet in the main pond, the sediment shall be removed. When the permanent pool depth reads 6.5 feet in the forebay, the sediment shall be removed. BASIN DIAGRAM (fill in the blanks) Permanent Pool Elevation 17.0 Sediment Removal E . 10.5 Pe manes Pool ---------------- -ftVolume Sediment Removal Elevation 10.5 Volume Bottom Elevatio 9.5 Min. ----------------------------- ----------- ------ Sediment Bottom Elevation 9.5 1-ft n Storage Sedimer Storage FOREBAY MAIN POND Form SW401-Wet Detention Basin O&M-Rev.4 Page 3 of 4 2,f Permit Number: (to be provider/ by DWQ) I acknowledge and agree by my signature below that 1 am responsible for the performance of the maintenance procedures listed above. I agree to notify DWQ of any problems with the system or prior to any changes to the system or responsible party. Project name:Stormwater Improvements for Commerce Park 11 BMP drainage area number: Print name: Address:PO Box 12006, New Bern, NC 28561 Note: The legally responsible party should not be a homeowners association unless more than 50% of the lots have been sold and a resident of the subdivision has been named the president. lT4.�n S , a Notary Public for the State of 1L vj pp County of f hys'.t1 do hereby certify that zalhl r Q ,' r personally appeared before me this day of 01 , and acknowledge the due execution of the forgoing wve�t�deQt-e�nt�ion basil maintenance requirements. Witness my hand and official seal, CAs�i�^^ itkOTA,R5- toUBLXC , •,.,,00 U NS SEAL 1' My commission expires Form SW401-Wet Detention Basin O&M-Rev.4 Page 4 of 4 Permit No. S'w'7lolaob no be provided by D WO) EXPRESS DEC 28 2010 ® � l WATf9O Nil DENR r o STORMWATER MANAGEMENT PERMIT APPLICATION FORM 401 CERTIFICATION APPLICATION FORM WET DETENTION BASIN SUPPLEMENT This form must be filled out, printed and submitted. The Required Items Checklist (Pad III) must be printed, filled out and submitted along with all of the required information. 1..P-ROJECTi INFORMATION Project name Site Improvement for Commerce Park II Contact person Bobby Billingsley, PE Phone number 252.637.2727 Dale 11.23.2010 Drainage area number 1 Drainage area Impervious area, post -development % impervious Design rainfall depth Storage Volume: Non-SAWaters Minimum volume required Volume provided Storage Volume: SA Waters 1,5' runoff volume Pre -development 1-yr, 24-hr runoff Post -development 1-yr, 24-hr runoff Minimum volume required Volume provided Peak Flow Calculations Is the prelpost control of the lyr 24hr stone peak flow required? 1-yr, 24-hr rainfall depth Rational C, pre -development Rational C, post -development Rainfall intensity: 1-yr, 24-hr stone Pre -development 1-yr, 24-hr peak flow Post -development 1-yr, 24-hr peak flow Pre/Post 1-yr, 24-hr peak flow control Elevations Temporary pool elevation Permanent pool elevation SHWT elevation (approx. at the permpool elevation) Top of 10ft vegetated shelf elevation Bottom of 1Oft vegetated shelf elevation Sediment cleanout, top elevation (bottom of pond) Sediment cleanout, bottom elevation Sediment storage provided Is there additional volume stored above the state -required temp. pool? Elevation of the top of the additional volume 122.841 ft7 71.28 % 1.5 in 14,863 ft3 Insufficient required volume. 23,225 ft3 OK, volume provided is equal to or in excess of volume required. rya ry3 ft3 If 0 Y (Y or N) 3.7 in 0.15 (unitless) 0.78 (uni8ess) 7.00 iNhr OK 4.15 ft3lsec 2.89 ft3/sec -1.26 ft3/sec 19.00 fmsl 17.00 fmsl to determine fmsl 17.50 fmsl 16.50 fmsl 10.50 first 9,50 fmsl 1,00 ft ti 1&. S_T-3 Inr17 N (Y or N) fmsl Form SW401-Wet Detention Basin-Rev.8-9I17I09 Pans I. & 11. Design Summary, Page 1 of 2 Permit No. (to be prcv,dsd by DWO) Surface Areas Area, temporary pool Area REQUIRED, permanent pool SAIDA ratio Area PROVIDED, permanent pool, A.. Area, bottom of 10H vegetated shelf, A. ,rel Area, sediment cleanout, top elevation (bottom of pond), A._p. Volumes Volume, temporary pool Volume, permanent pool, Vperm�od Volume, forebay (sum of forebays if more than one forebay) Forebay % of permanent pool volume SAIDA Table Data Design TSS removal Coastal SAIDA Table Used? Mountain/Piedmont SAIDA Table Used? SAIDA ratio Average depth (used in SA/DA table): Calculation option 1 used? (See Figure 10-2b) Volume, permanent pool, V.-. Area provided, permanent pool, Apra,,,, Average depth calculated Average depth used in SAIDA, J., (Round to nearest 0.5ft) Calculation option 2 used? (See Figure 10-2b) Area provided, permanent pool, A.. Area, bottom of 1Oft vegetated shelf, Abd rasa Area, sediment cleanout, top elevation (bottom of pond), Ab. 'Depth' (distance b/w bottom of 1 Oft shelf and top of sediment) Average depth calculated Average depth used in SAIDA, dm„ (Round to nearest 0.5ft) Drawdown Calculations Drawdown through orifice? Diameter of orifice (it circular) Area of orifice (if-noncircular) Coefficient of discharge (Co) Driving head (Ho) Drawdown through weir? Weir type Coefficient of discharge (C.„) Length of weir (L) Driving head (H) Pre -development l-yr, 24-hr peak flow Post -development 1-yr, 24-hr peak flow Storage volume discharge rate (through discharge orifice or weir) Storage volume drawdown time Additional Information Vegetated side slopes Vegetated shelf slope Vegetated shelf width Length of flowpath to width ratio Length to width ratio Trash rack for overflow & onfice? Freeboard provided Vegetated filter provided? Recorded drainage easement provided? Capures all runoff at ultimate build -out? Drain mechanism for maintenance or emergencies is: Form SW401-Wet Detention Basin-Rev.8-9I17I09 613,4165�pr.n0 8,789 ft' 5.10 (unitless) 8,850 ft3 OK 6,788 ft' 3,404 ft' 23,225 ft3 OK 34,486 ft3 6,478 k3 18.8% % OK 90 % Y (Y or N) N (Y or N) 5.10 (unitless) N (Y or N) 34,486 ft3 8,850 ft' ft Need 3 ft min. ft Y (Y or N) 8,850 ft, (` 6,788 ft3 Lo ,`14j -l� 3,404 ft2 ,% 6.00 ft 4.94 k OK 5.0 ft- OK Y (Y or N) 1.25 in in 0.60 (unitless) 1.50 ft (Y or N) (unitless) (unitless) ft ft 4.15 ft3/sec 2.89 ft3/sec 0.04 ft3/sec 2.00 days 3 :1 10 :1 OK, draws down in 2-5 days. OK OK 10.0 It OK 3 :1 Insufficient flow path to width ratio. Must not short-circuit pond. 2.6 :1 OK Y (Y or N) OK 1.5It OK N (Y or N) OK Y (Y or N) OK Y (Y or N) OK Mechanical Pumps Parts I. & II. Design Summary, Page 2 of 2 Permit III. REQUIRED ITEMS CHECKLIST (to be provided by DWO) 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. Pagel Plan Initials Sheet No. /L r, 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), - Basin dimensions, - Pretreatment system, - High flow bypass system, - Maintenance access, - Proposed drainage easement and public right of way (ROW), - Overflow device, and - Boundaries of drainage easement. 4 Lld 2. Partial plan (1" = 30' or larger) and details for the wet detention basin showing: - Outlet structure with trash rack or similar, - Maintenance access, - Permanent pool dimensions, - Forebay and main pond with hardened emergency spillway, - Basin cross-section, - Vegetation specification for planting shelf, and - Filter strip. 3. Section view of the wet detention basin (1" = 20' or larger) showing: - Side slopes, 3:1 or lower, - Pretreatment and treatment areas, and - Inlet and outlet structures. /Z 4. If the basin is used for sediment and erosion control during construction, clean out of the basin is specified on the plans prior to use as a wet detention basin. �L L� 5. A table of elevations, areas, incremental volumes & accumulated volumes for overall pond and for Forebay, to verify volume provided. 6. A construction sequence that shows how the wet detention basin will be protected from sediment until the entire drainage area is stabilized. 7. The supporting calculations. 8. A copy of the signed and notarized operation and maintenance (O&M) agreement. /2 t O 9. A copy of the deed restrictions (if required). 124,6 10. A soils report that is based upon an actual field investigation, soil borings, and infiltration tests. County soil maps are not an acceptable source of soils information. Form SW401-Wet Detention Basin-Rev.8-9/17/09 Part III, Required Items Checklist, Page 1 of 1 SCS Type III Storage Routing Stormwater Improvements for Commerce Park II - Wet Detention Pond Design Stonn = SCS Type III Hydrograph 1 yr Storm 7.00 cfs flow I yr Storm 3.7 in/24 yr precipitation C pre 0.15 C post 0.78 Imp. Area 122841 sf post development Total Area 172329 sf �Qpre -� �4.15 cfs rational method Pond Storage for l yr/24 hour precipitation Rv 0.69 V 36745 cf <==lyr/24 hr Storm Volume Pond Storage 23225 of <==Design Time Prec. Ratio I yr storm (in) Inflow (ft3) Storage (ft3) Outflow (fl3)/ Qufflow (cfs) 0.0 0.00000 0.00000 0.2 0.00200 0.00740 73.49 73.49 0.00 0.00 0.4 0.00400 0.01480 73.49 146.98 0.00 0.00 0.6 0.00600 0.02220 73.49 220.47 0.00 0.00 0.8 0.00800 0.02960 73.49 293.96 0.00 0.00 1.0 0.01000 0.03700 73.49 367.45 0.00 0.00 1.2 0.01200 0.04440 73.49 440.94 0.00 0.00 1.4 0.01400 0.05180 73.49 514.43 0.00 0.00 1.6 0.01600 0.05920 73.49 587.92 0.00 0.00 1.8 0.01800 0.06660 73.49 661.41 0.00 0.00 2.0 0.02000 0.07400 73.49 734.90 0.00 0.00 2.2 0.02203 0.08151 74.59 809.49 0.00 0.00 2.4 0.02412 1 0.08924 76.80 886.29 0.00 0.00 2.6 0.02627 0.09720 79.00 965.29 0.00 0.00 2.8 0.02848 0.10538 81.21 1046.50 0.00 0.00 3.0 0.03080 0.11396 85.25 1131.75 0.00 0.00 3.2 0.03308 0.12240 83.78 1215.53 0.00 0.00 3.4 0.03547 0.13124 87.82 1303.35 0.00 0.00 3.6 0.03792 0.14030 90.03 1393.37 0.00 0.00 3.8 0.04043 0.14959 92.23 1485.61 0.00 0.00 4.0 0.04300 0.15910 94.43 1580.04 0.00 0.00 4.2 0.04563 0.16883 96.64 1676.68 0.00 0.00 4.4 0.04832 0.17878 98.84 1775.52 0.00 0.00 4.6 0.05107 0.18896 101.05 1876.57 0.00 0.00 4.8 0.05388 0.19936 103.25 1979.83 1 0.00 0.00 5.0 0.05670 0.20979 103.62 2083.45 0.00 0.00 5.2 0.05968 0.22082 109.50 2192.95 0.00 0.00 5.4 0.06267 1 0.23188 109.87 2302.82 0.00 0.00 5.6 0.06572 0.24316 112.07 2414.89 0.00 0.00 5.8 0.06883 0.25467 114.28 2529.17 0.00 0.00 6.0 0.07200 0.26640 116.48 2645.65 0.00 0.00 6.2 0.07530 0.27861 121.26 2766.91 0.00 0.00 6.4 0.07880 0.29156 128.61 2895.52 0.00 0.00 6.6 0.08250 0.30525 135.96 3031.47 0.00 0.00 6.8 0.08640 0.31968 143.31 3174.78 0.00 0.00 7.0 0.09050 0.33485 150.65 3325.43 0.00 0.00 7.2 0.09480 0.35076 158.00 3483.44 0.00 0.00 7.4 0.09930 0.36741 165.35 3648.79 0.00 0.00 7.6 0.10400 0.38480 172.70 3821.49 0.00 0.00 7.8 0.10890 0.40293 180.05 4001.54 0.00 0.00 8.0 0.11400 0.42180 187.40 4188.94 0.00 0.00 8.2 0.11943 0.44189 199.53 4388.47 0.00 0.00 8.4 0.12532 0.46368 216.43 4604.90 0.00 0.00 8.6 0.13167 0.48718 233.33 4838.23 0.00 0.00 8.8 0.13848 0.51238 250.23 5088.46 0.00 0.00 9.0 0.14580 0.53946 268.97 5357.44 0.00 0.00 9.2 0.15348 0.56788 282.20 5639.64 0.00 0.00 9.4 0.16167 0.59818 300.94 5940.58 0.00 0.00 9.6 0.17032 0.63018 317.85 6258.43 0.00 0.00 9.8 0.17943 0.66389 334.75 6593.18 0.00 0.00 10.0 0.18900 0.69930 351.65 6944.83 0.00 0.00 10.2 0.19928 0.73734 377.74 7322.57 0.00 0.00 10.4 0.21052 0.77892 413.02 7735.58 0.00 0.00 10.6 0.22272 0.82406 448.29 8183.87 0.00 0.00 10.8 0.23588 0.87276 483.57 8667.44 0.00 0.00 11.0 0.25000 0.92500 518.84 9186.28 0.00 0.00 11.2 0.26644 0.98583 604.09 9790.37 0.00 0.00 11.4 0.28656 1.06027 739.31 10529.68 0.00 0.00 11.6 0.31430 1.16291 1019.31 11548.99 0.00 0.00 11.8 0.37330 1.38121 2167.96 13716.95 0.00 0.00 12.0 0.50000 1.85000 4655.61 18372.56 0.00 0.00 12.2 0.62670 2.31879 4655.61 23028.16 0.00 0.00 12.4 0.68570 2.53709 2167.96 25196.13 2167.96 _.89 12.6 0.71344 2.63973 1019.31 26215.44 1019.31 1.36 12.8 0.73336 2.71342 731.82 26947.25 731.82 0.98 13.0 0.75000 2.77500 611.59 27558.84 611.59 0.82 13.2 0.76412 2.82724 518.84 28077.69 518.84 0.69 13.4 0.77728 2.87594 483.57 28561.24 483.57 0.64 13.6 0.78948 2.92108 448.29 29009.53 448.29 0.60 13.8 0.80072 2.96266 413.02 29422.55 413.02 0.55 14.0 0.81100 3.00070 377.74 29800.29 377.74 0.50 14.2 0.82057 3.03611 351.65 30151.94 351.65 0.47 14.4 0.82968 3.06982 334.75 30486.69 334.75 0.45 14.6 0.83833 3.10182 317.85 30804.53 317.85 0.42 14.8 0.84652 3.13212 300.94 31105.48 300.94 0.40 15.0 0.85430 3.16091 285.88 31391.35 295.88 0.38 15.2 0.86152 3.18762 265.30 31656.65 265.30 0.35 15.4 0.86833 3.21282 250.23 31906.89 250.23 0.33 15.6 0.87468 3.23632 233.33 32140.22 233.33 0.31 15.8 0.88057 3.25811 216.43 32356.65 216.43 0.29 16.0 0.88600 3.27820 199.53 32556.17 199.53 0.27 16.2 0.89110 3.29707 187.40 32743.57 187.40 0.25 16.4 0.89600 3.31520 180.05 32923.62 180.05 0.24 16.6 0.90070 3.33259 172.70 33096.33 172.70 0.23 16.8 0.90520 3.34924 165.35 33261.68 165.35 0.22 17.0 0.90950 3.36515 158.00 33419.68 158.00 0.21 17.2 0.91360 3.38032 150.65 33570.34 150.65 0.20 17.4 0.91750 3.39475 143.31 33713.64 143.31 0.19 17.6 0.92120 3.40844 135.96 33849.60 135.96 0.18 17.8 0.92470 3.42139 128.61 33978.21 128.61 0.17 18.0 0.92800 3.43360 121.26 34099.47 121.26 0.16 18.2 0.93117 3.44533 116.48 34215.95 116.48 0.16 18.4 0.93428 3.45684 114.28 34330.23 114.28 0.15 18.6 0.93733 3.46812 112.07 34442.30 112.07 0.15 18.8 0.94032 3.47918 109.87 34552.17 109.87 0.15 19.0 0.94330 3.49021 109.50 34661.67 109.50 0.15 19.2 0.94612 3.50064 103.62 34765.29 103.62 0.14 19.4 0.94893 3.51104 103.25 34868.54 103.25 0.14 19.6 0.95168 3.52122 101.05 34969.59 101.05 0.13 19.8 0.95437 3.53117 98.84 35068.44 98.84 0.13 20.0 0.95700 3.54090 96.64 35165.08 96.64 0.13 20.2 0.95958 3.55045 94.80 35259.88 94.80 0.13 20.4 0.96211 3.55981 92.97 35352.84 92.97 0.12 20.6 0.96460 3.56902 91.50 35444.34 91.50 0.12 20.8 0.96704 3.57805 89.66 35534.00 89.66 0.12 21.0 0.96940 3.58678 86.72 35620.72 86.72 0.12 21.2 0.97179 3.59562 87.82 35708.54 87.82 0.12 21.4 0.97410 3.60417 84.88 35793.42 84.88 0.11 21.6 0.97636 3.61253 83.04 35876.46 83.04 0.11 21.8 0.97858 3.62075 81.57 35958.04 81.57 0.11 22.0 0.98080 3.62896 81.57 36039.61 81.57 0.11 22.2 0.98288 3.63666 76.43 36116.04 76.43 0.10 22.4 0.98496 3.64435 76.43 36192.47 76.43 0.10 22.6 0.98700 3.65190 74.96 36267.43 74.96 0.10 22.8 0.98899 3.65926 73.12 36340.55 73.12 0.10 23.0 0.99090 3.66633 70.18 36410.74 70.18 0.09 23.2 0.99284 3.67351 71.29 36482.02 71.29 0.10 23.4 0.99470 3.68039 68.35 36550.37 68.35 0.09 23.6 0.99651 3.68709 66.51 36616.88 66.51 0.09 23.8 0.99828 3.69364 65.04 36681.91 65.04 0.09 24.0 1.00000 3.70000 63.20 36745.12 63.20 0.08 �� -�� C �� • �� , �� . -�� - �� .�� .�� .�� C�� . �� Permit No. (fo be provMetl by D 0) RECEIVE® APR - 9 2012 ATA �/� � NCDENR STORMWATERMANAGEMENTPERMITAQCATfOtJF �® 401 CERTIFICATION APPLICATION FORM WET DETENTION BASIN SUPPLEMENT This form must be filled out, printed and submitted. The Required Items Checklist (Part III) must be printed, filled out and submitted along with all of the required information. I. PROJECT INFORMATION Project name Site Improvement for Commerce Park II Contact person Bobby Billingsley, PE Phone number Date Drainage area number II. DESIGN INFORMATION Site Characteristics 11.23.2010 (REVISED 4.5.2012) 1 Drainage area 194,329 e Impervious area, post -development 138,341 ft' %impervious 71.19 % Design rainfall depth 1.5 in Storage Volume: Non -SA Waters Minimum volume required 16,800 g' Volume provided 23,225 ft' Storage Volume: $A Waters 1.5' runoff volume It, Pre -development 1-yr, 24-hr runoff ft' Post -development 1-yr, 24-hr runoff ft' Minimum volume required ft' Volume provided to Peak Flow Calculations OK o�O p WATf9O -O� ; OK, volume provided is equal to or in excess of volume required. Is the pre/post control of the lyr 24hr stone peak flow required? Y (Y or N) 1-yr, 24-hr rainfall depth 3.7 in Rational C, pre -development 0.15 (unifless) Rational C, post -development 0.78 (unitiess) Rainfall intensity: 1-yr, 24-hr storm 7.00 in/hr OK Pre -development 1-yr, 24-hr peak flow 4.15 ft'/sec Post -development 1-yr, 24-hr peak flow 239 ft3/sec Pre/Post 1-yr, 24-hr peak flow control -1.26 ft'Isec Elevations Temporary pool elevation 19.00 fmsl Permanent pool elevation 17.00 fmsl SHWT elevation (approx. at the perm. pool elevation) to determine fmsl Top of 1 Oft vegetated shelf elevation 17.50 fmsl Bottom of 10ft vegetated shelf elevation 16.50 fmsl Sediment cleanou6 top elevation (bottom of pond) 1o.50 fmsl Sediment deanoul, bottom elevation 9.50 fmsl Sediment storage pmvided 1.00 It Is there additional volume stored above the state -required temp. pool? N (Y or N) Elevation of the top of the additional volume fmsl Fore SW401-Wet Detention 6asin-Rev.e-9/17/09 Parts I. & II. Design Summary, Page 1 of 2 Permit No. (to be jam ded by DWO) II. DESIGN INFORMATION Surface Areas Area, temporary pool 18,245 ftz Area REQUIRED, permanent pool 9,911 If SAIDA ratio 5.10 (unidess) Area PROVIDED, permanent pool, Ap,,,,_y,l 8,850 ft` Insufficient permanent pool surface area Area, bottom of 10ft vegetated shelf, A�vmw 6,788 ft p Area, sediment cleancut, top elevation (bottom of pond), A�„a 3,404 fl` K T ,jCDENe 9 t 4 v t— Volumes `190. 5corr VI^)S0.1— Volume, temporary pool 23,225 ft' Volume, permanent pool, Vp,,,, 34,486 Ill Volume, forebay (sum of forebays if more than one forebay) 6,478 ft' Forebay %of permanent pool volume 18.8% % SAIDA Table Data Design TSS removal Coastal SAIDA Table Used? MountainlPiadmont SAIDA Table Used? SAIDA ratio Average depth (used in SAIDA table): Calculation option i used? (See Figure 10-2b) Volume, permanent pool, Vp,,,,p, Area provided, permanent pool, A, ,.,,, jw Average depth calculated Average depth used in SAIDA, dw, (Round to nearest 0.511) Calculation option 2 used? (See Figure 10-21h) Area provided, permanent pool, Ar,,, Area, bottom of 10ft vegetated shelf, A,,(_ r 90 % Y (Y or N) N (Y or N) 5.10 (unidess) N (Y or N) 34,486 ft' 8,850 ft ft Y (Y or N) 8,850 ft 6,788 ft` OK 70 Need 3 If min. Area, sediment cleanout, top elevation (bottom of pond), A,,., 3,404 e 'Depth' (distance blw bottom of 10ft shelf and top of sediment) 6.00 It Average depth calculated 4.94 ft OK Average depth used in SAIDA, dr, (Round to nearest 0.511) 5.0 It OK Drawdown Calculations Drawdown through orifice? Y (Y or N) Diameter of office (if circular) 1.25 in Area of orifice (if-noncimular) in2 Coefficient of discharge (Co) 0.60 limitless) Odvirg head (Ho) 2.00 It Drawdown through weir? (Y or N) Weir type limitless) Coefficient of discharge (C„) (unidess) Length of weir (L) ft Driving head (H) ft Pre -development 1-yr, 24-hr peak flow 4.15 ft'/sec Post -development 1-yr, 24-hr peak flow 2.89 ft'/sec Storage volume discharge rate (through discharge orifice or weir) 0.04 ft'/sec Storage volume drawdown lime 2.00 days Additional Information Vegetated side slopes Vegetated shelf slope Vegetated shelf width Length of flowpath to width ratio Length to width ratio Trash rack for overflow & orifice? Freeboard provided Vegetated filter provided? Recorded drainage easement provided? Capures all runoff at ultimate build -out? Drain mechanism for maintenance or emergencies is: AA.A{LGK 27l7-0/2- OK, draws down in 2-5 days. 3:1 OK 10 :1 OK 10.0 ft OK 3 :1 Insufficient flow path to width ratio. Must not short-circuit pond. 2.6 :1 OK Y (Y or N) OK 1.5ft OK N (Y or N) OK Y (Y or N) OK Y (Y or N) OK Mechanical Pumps Fonn SW401-Wet Detention Basin-Rev.a-9117/09 Parts I. & J. Design Summary, Page 2 of 2