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HomeMy WebLinkAboutSW7970812_HISTORICAL FILE_20180615STORMWATER DIVISION CODING SHEET POST -CONSTRUCTION PERMITS PERMIT NO. SW_��7do� DOC TYPE ❑ CURRENT PERMIT ❑ APPROVED PLANS HISTORICAL FILE ❑ COMPLIANCE EVALUATION INSPECTION DOC DATE YYYYMMDD Energy, Mineral and Land Resources ENVIRONMENTAL QUALITY Coastal Regional Airport Authority Attn: Andrew Shorter 200 Terminal Drive New Bern, NC 28562 June 15, 2018 Subject: Approved Plan Revision 97 Terminal Improvements Stormwater Project No. SW7970812 Craven County Dear Andrew Shorter: ROY COOPER Goremar MICHAEL S. REGAN Secreteny TOBY VINSON Interim Dreaor On May 9, 2018, the Washington Regional Office received a Plan Revision request for Stormwater Management Permit Number SW7970812. The plan revision request is for the following: Adding 1.35 acres of impervious area to the current 10.98 acres of impervious area for a total of 12.33 acres. The permit allows for a maximum of 14.20 acres of impervious area. Based on the current Division of Energy, Mineral, and Land Resources guidance on this issue your plan revision request is hereby approved. Please incorporate the approved plan set (attached) into your existing set and permit file. Please remember that your current permit is issued for a total of 14.20 acres of impervious area. If at any point in future, your project exceeds the allowable impervious area 14.20 acres, the permit will have to be modified. Please be aware that all terms and conditions of the original permit issued on March 19, 1998 and renewal permit issued on August 30, 2007 remain in full force and effect until August 30, 2021, at which time the permit must be renewed. Please also understand that the approval of this revision to the approved plans for the subject State Stormwater Permit is done on a case -by -case basis. Any other changes to this project must be submitted to and approved through the Division of Energy, Mineral, and Land Resources prior to construction. The issuance of this plan revision does not preclude the permittee from complying with all other applicable statutes, rules, regulations or ordinances which may have jurisdiction over the proposed activity, and obtaining a permit or approval prior to construction. If you have any questions, or need additional information concerning this matter, please contact me at (252) 946-6481. Sincerely, William Carl Dunn, PE Environmental Engineer cc: Pamela Culp, PE. — Talbert 8 Bright, Inc. (4810 Shelley Dr., Wilmington, NC 28405) Craven County Inspections (2828 Neuse Blvd, New Bern, NC 28561) Washington Regional Office State of North Carolina I Environmental Quality I Energy, Mineral and Land Resources 1612 Mail Service Center 1 512 N. Salisbury St. I Raleigh, NC 27699 919 707 9200 T Itsn-'ll/«i7_13iI�f�I_� txe7[iI�G\�\I �Zi];ii AIR CARRIER APRON RECONSTRUCTION AND EXPANSION TOTAL PROJECT AREA TO POND ONLY (26 ACRES TOTAL DA, 14.2 ACRES IMPERVIOUS ALLOWED) SW PERMIT 7970812 (ACRES) EXISTING (ACRES) 0.76 PROPOSED (ACRES) 0 TOTAL (ACRES) 0.76 ULT BUILD OUT ALLOWED BUILDINGS 1 ROADS 3.1 2.31 0 2.31 (ACRES) PARKING 8.2 3.89 0 3.89 APRON 6.9 4.02 1.35 5.37 TOTAL 19.2 10.98 1 1.35 � 14.2 i�Ch��liE� �'�AY 201% RUNWAY 4-22 11 l ! !II I i WET DETENTION BASIN ! (SW PERMIT 7970812) ! COASTAL CAROLINA REGIONAL AIRPORT AIR CARRIER APRON RECONSTRUCTION AND EXPANSION SW PERMIT 7970812 - MINOR MODIFICATION t- 4 w6al LEGEND DRAINAGE AREA TO WET DEtENTION BASIN 300 150 0 0 (PERMIT SW7970812) 0 EXISTING IMPERVIOUS SCALE IN FEET PROPOSED IMPERVIOUS WITH THIS PROJECT 1 "= 300' inKu2C) �OF W A?Fqo Michael F. Easley, Governor William G. Ross Jr., Secretary r North Carolina Department of Environment and Natural Resources Q 'N� Colecn 1-I. Sullins, Director Division of Water Quality March 12, 2008 Mr. Tom Braaten Craven County Regional Airport Authority P.O. Box 3258 New Bern, NC 28564 Subject: Stormwater Review SW7080219 Airport drainage improvements Project Craven County Dear Mr. Braaten: The Washington Regional Office received a copy of your Sedimentation and Erosion Control application for the proposed drainage improvements at the Craven County Airport on February 25, 2008. Staff has determined that the project, as proposed, consists of activities that will not pose new surface water quality threats from stormwater runoff since no significant new impervious area is proposed. The Director has determined that projects that are reviewed and approved by the Division as not posing water quality threats from stormwater runoff should not be subject to the stormwater management permitting requirements of 15A NCAC 21-1.1000. For this reason, we are informing you by way of this letter that your project will not require a stormwater management permit. Please keep in mind that this determination does not affect your legal requirements to obtain other permits which may be required by the Division of Water Quality, the Division of Land Resources, Coastal Area Management Act or any other Federal, State or Local Government. In addition, any future modifications to the project will require additional review from this office to assure that stormwater impacts are not an issue. If you have any questions or need additional information concerning this matter, please contact me or Roger Thorpe at (252) 946-6481. AHo ely,ge, Reggio( a�soT r-- Surface Water Protection Section Washington Regional Office cc: The LPA Group of North Carolina, p. a. Washington Regional Office Central Files North Carolina Division of Water Quality Internet: �caw.nacaierclualitv.ore 943 Washington Square Mall Phone (252) 946-6481 Washington, NC 27889 Fay (252) 946-9215 NorthCarolina Naturally An Equal Opportunity/Affirmative Action Employer — 50% Recycled110% Post Consumer Paper wrypgaal9 KLII.o fiN/�L� °9 FEB 2 5 2008 FINANCIAL RESPONSIBILITY/OWNERSHIP FORM SEDIMENTATION POLLUTION CONTROL ACT DWQ-WAR® No person may initiate any land -disturbing activity on one or more acres as covered by the Act before this form and an acceptable erosion and sedimentation control plan have been completed and approved by the Land Quality Section, N.C. Department of Environment and Natural Resources. (Please type or print and, if the question is not applicable or the e-mail and/or fax information unavailable, place N/A in the blank.) Part A. 1. Project Name: Craven County Regional Airport — Drainage Improvements 2. Location of land -disturbing activity: County Craven City or Township New Bern Highway/Street SR 1175 Aviation Drive Latitude 35"04'22.74" N Longitude 77002'34.57" W 3. Approximate date land -disturbing activity will commence: May 2008 4. Purpose of development (residential, commercial, industrial, institutional, etc.): Airport/Commercial 5. Total acreage disturbed or uncovered (including off -site borrow and waste areas): 10 acres 6. Amount of fee enclosed: $ 650.00. The application fee of $65.00 per acre (rounded up to the next acre) is assessed without a ceiling amount (Example: a 9-acre application fee is $585). 7. Has an erosion and sediment control plan been filed? Yes No X Enclosed. X 8. Person to contact should erosion and sediment control issues arise during land- . 0 W R Name Jason L. Elliott E-mail Address ilelliott5lo IT0111 D Telephone (919) 954-1244 Cell # Fax # 9 4 5 9. Landowner(s) of Record (attach accompanied page to list additional owners) Craven County Regional Airport Authority (252) 638-8591 L 42r2� aza 10AM0 Name Telephone Fax Number P.O. Box 3258 200 Terminal Drive Current Mailing Address Current Street Address New Bern, City North Carolina 28564 State Zip New Bern North Carolina City State �� i vi L.���® 10. Deed Book No. 1129 Page No. 0006 Provide a copy of the most current deed. FEB 2 3 9r1�1 Part B. LAND QUALITY SECTION 1. Person(s) or firm(s) who are financially responsible for the land -disturbing V#$H V Ffl \REGIQNALOFFICE comprehensive list of all responsible parties on an attached sheet): Craven County Regional Airport Authority Tom Braaten tbraaten(o)newbernairport com Name E-mail Address P.O. Box 3258 Current Mailing Address New Bern, North Carolina 28564 City State Zip 200 Terminal Drive Current Street Address New Bern, North Carolina 28562 City State Zip Telephone (252)638-8591 Fax Number (252) 638-5930 Wq 2. (a) If the Financially Responsible Party is not a resident of North Carolina, give name and street address of the designated North Carolina Agent: Name Current Mailing Address City State Zip Telephone E-mail Address Current Street Address Fax Number State Zip (b) If the Financially Responsible Party is a Partnership or other person engaging in business under an assumed name, attach a copy of the Certificate of Assumed Name. If the Financially Responsible Party is a Corporation, give name and street address of the Registered Agent: Name of Registered Agent E-mail Address Current Mailing Address Current Street Address City State Zip City State Zip ,I � _T. tepho7A"'""" :"='1 Fax Number Il�,.i W h r!f r-•�al {: The aboveWrma t, is true and correct to the best of my knowledge and belief and was provided cgiind ath1. form must be signed by the Financially Responsible Person if an individual �_or his attorney-in-Sact, r if not an individual, by an officer, director, partner, or registered agent with 3Uii�Uthetauthofityjjqule instruments for the Financially Responsible Person). I agree to provide correctedlinformation should there be any change in the information provided herein. Tom Braaten Type or print parige Signature Airport Director Title or Authority Date a Notary Public of the County ofci t (1 State of North Carolina, hereby certify that �u m 12C�o_ n appeared personally before me this day and being duly sworn acknowledged that the above form was executed by him. II Witness my hand and notariaj.seal, this day of �t,ux—c— t , 20 C Notary Notary Seal '. Public /: My commission expires .'a c1— L NJATHE LPA GROUP of North Carolina, p.a. Transportation Consultants 5000 FALLS OF NEUSE ROAD, SUITE 304 ■ RALEIGH, NORTH CAROLINA 27609 ■ 919-954-1244 ■ FAX 919-954-1345 August 3, 2007 Mr. Bill Moore NCDENR, Division of Water Quality Washington Regional Office 943 Washington Square Mall Washington, North Carolina 27889 Re: Craven County Regional Airport 1997 Terminal Improvements Dear Bill: AUG - 6 2007 Enclosed please find one copy of the Coastal Stormwater Permit Renewal Application Form for the above referenced project. Also enclosed, please find the Wet Detention Basin Operation and Maintenance Agreement and the Designer's Certification for the wet detention pond. The required check in the amount of $420.00, to cover the fee for plan review, is also enclosed. If you have any questions or need additional information, please do not hesitate to call. Sincerely, THE LPA GROUP �of/JNorth Carolina, p.a. Brigid Z. Williams, PE Aviation Design Engineer Enclosures Member of THE LPA GROUP INCORPORATED ATLANTA ■ BATON ROUGE ■ CHARLOTTE ■ COLUMBIA ■ GREENSBORO • JACKSONVILLE KNOXVILLE ■ LITTLE ROCK ■ MOBILE ■ ORLANDO ■ RALEIGH ■ SARASOTA ■ TALLAHASSEE ■ TAMPA ■ WEST PALM BEACH AUG - 6 2007 June 12, 2007 Craven County Regional Airport Authority Attn: James Creech, Chair Post Office Box 3258 New Bern, NC 28564-2358 Subject:: Stormwater Permit No. SW7970812 Craven Airport — 97 Terminal ImprO% Craven County Dear Mr. Creech: Michael F. Easley, Governor North Carolina Department of William G. Ross Jr., Secretary Environment and Natural Resources Department Head: Account# Coleen H. Sullins, Director Division of Water Quality Finance Dept: Amount The Division of Water Quality issued a Coastal Stormwater Management Permit, Number SW7970812 for Craven Airport — 97 Terminal Improvements on March 19, 1998. This permit expires on March 19 2008: Section s shall of 15.A #CAC 2H .1000 (the stormwaterrules) requires that applications for Permit renewals shall be submitted 180 days prior to the expiration of a permit and must be accompanied b a his I please complete and submit it is n clos dwhich i renewaltappl cation in a timely manner. If this project h been constructed and s permit is no longer needed, please et at $ ubmiitt a request tollhave he permit as not rescinded. If you have sold the project, or are no longer the permittee, please provide the name, mailing address and phone number of the person or entity that is now respponsible for this permit. Enclosed is a form for change of ownership, which should be completed and submitted if the property has changed hands. Your permit requires that upon completion of construction and prior to operation of thepermitted treatment unitsn certification of completion be submitted to the Division from an appropriate designer for the system installed. This is to certify that the permitted facility has been installed in accordance with the permit, the approvedhisPlans, specifications and Permitted rdan the certification with your permit. renewal request and processing fee. Enclosed Please include a a co certification. Also enclosed' anew Operation. and Maintenance agreement that should be om late and submitted along with Your renewal application. copy of a sampleof You should be aware that failure to provide the Designer's Certification and the operation P d stormwater treatment facility without a valid permit, are violations of NC General Statute 143-215.1 and may result in appropriate enforcement action including the assessment of civil p $10, result per day. If you have any questions, please feel free to contact us at 252-946-6481. enalties of up to Enclosures eglonal Supervisor :er Protection Section Regional Office cc: The LPA Group of NC, PA, 4904 Professional Court, Suite 201, PO Box 17736, Raleigh, NC 27619 Washington Regional Office North Caroline bivision of water Quality 943 Washington Square Mall - Internet: w yw nc . eti� Washington. NC 27889 Phone (252) 946.6481 ne Fax (252)946-9215 �/'J►•►/�l[-fJhiCk"t0lliina An Equal OPPortunlly/AtftmaWe Action Employer -50%Recycled/10% Post Consumer Papa, ' ' -_�Kra4 Airport Authority CRAVEN REGIONAL Cu Curtis Bare Bare James Creech Scott Dacey AIRPORT Royce Jordan William Naumann John Price ' (11ountp Clemens Schaller Fletcher Watts Airport Director W1,2 Thomas Braaten September 26, 2007 200 Terminal Drive P.O. Box 3258 New Bern, NC 28564 E-mail: admin@newbernairport.com Web: www.newbernairporl.com (252) 638-8591 Fax (252) 638-5930 Response to Notice of Violation — Permit SW7970812 dated August 30, 2007 RECEIVED Mr. Al Hodge Regional Supervisor, Surface Water Protection SEP 2 8 2007 North Carolina Division of Water Quality Washington NC 27889 DW(''_W RO Dear Mr. Hodge, This letter is in response to the Notice of Violation issued to the Craven County Regional Airport resulting from an inspection on August 28, 2007 in connection with our request for the renewal of permit SW7970812. The inspection revealed that the grass on the side slopes was not mowed to the proper maximum height of six inches and records of maintenance activities were not available. The airport takes our environmental stewardship seriously, and I neglected to have the proper maintenance performed through my ignorance. I have been the Airport Director for a little over one year. Shortly before I assumed my position, the former Operations Officer left the airport's employ. As this is my first position with a civilian airport, I have spent the bulk of my time becoming familiar with FAA and TSA requirements. I now know that there are a series of questions that I should have asked, but did not. Since receiving your letter, we have been busy. The grass on the side slopes was mowed to less than six inches the day after I received the notification. I have studied the permit that was signed in 1999. We had an engineer conduct a survey to see if we had a problem with sedimentation in the forebay or the main pond. There were a few places that did not follow the contours on the original design due to an accumulation of sediment. 1 have hired Trader Construction to restore the pond to its original design. They positioned their equipment this afternoon and will commence work tomorrow morning (September 27"i). The foreman's estimate is to complete the task within two days. Unable to locate previous records of maintenance records for the stormwater treatment facility, I solicited the assistance of our airport consulting firm to develop a comprehensive checklist to ensure that we not only complete, but also maintain records of our maintenance activities. I have spent time with our maintenance crew to ensure that they understand what must be done at what interval. Serving Eastern North Carolina for 75 years Aerial Gateway to North Carolina's Central Coast Craven Regional Airport I have also scheduled a monthly check of the pond and the Pond Maintenance Log on my personal calendar. 1 would like to reiterate that the Craven County Regional Airport takes their environmental responsibilities seriously. I have apologized to my Board for my ignorance and for failing to successfully comply with the requirements of our permit. I also briefed them and received their concurrence on my course of action to correct the discrepancies. I believe the procedures now in place will allow us to maintain our facility as required. I appreciate the assistance of our consultant, the LPA Group of NC, which has been helpful in my education process and in preparing our checklist. I also appreciate your offer of assistance from Mr. Ernest Odei-Larbi or you should we have questions. Sincerely, Tom Braaten Airport Director Craven County Regional Airport CRAVEN COUNTY REGIONAL AIRPORT OPERATION AND MAINTENANCE LOG FOR TERMINAL APRON WET DETENTION BASIN Date of Inspection: Inspection Performed By: Check all that apply: Inspection after runoff producing rain event Monthly Inspection Quarterly Inspection Semi -Annual Inspection Maintenance to be performed after every significant runoff producing rainfall event and at least monthly: 1 General Condition of Wet Detention Basin: 2 Inspect main pond, outlet structure and forebay for trash and debris accumulation. Condition Acceptable Condition Not Acceptable Action Taken/Remarks (include date of repair if applicable): 3 Conduct visual inspection of sediment accumulation in forebay. Condition Acceptable Condition Not Acceptable Action Taken/Remarks (include date of repair if applicable): 4 Inspect main pond and forebay perimeter for areas of bare soil or erosion. Repair eroded areas immediately. Re -seed as necessary to maintain good vegetative cover. Condition Acceptable Condition Not Acceptable Action Taken/Remarks (include date of repair if applicable): 5 Inspect vegetation height. Maintain vegetation at a height of approximately 6 inches. Condition Acceptable Condition Not Acceptable Action Taken/Remarks (include date of repair if applicable): 6 Inspect and clear orifice on outlet structure of any obstructions. Inspect outlet device for damage. Repair or replace as necessary. Condition Acceptable Condition Not Acceptable Action Taken/Remarks (include date of repair if applicable): Maintenance to be performed after every significant runoff producing rainfall event and at least monthly: 7 Cattails and other indigenous wetland plants should be removed when they cover 50% of the basin surface. Cattails shall not be removed from the vegetated shelf or forebay berm. Remove all shrubs, trees, and other weeds. Condition Acceptable Condition Not Acceptable Action Taken/Remarks (include date of repair if applicable): 8 Inspect algae growth covers in forebay and main pond. Algae should not cover more than 50% of the area. Condition Acceptable Condition Not Acceptable Action Taken/Remarks (include date of repair if applicable): Maintenance to be performed quarterly: 9 Inspect and repair the collection system including catch basins, pipes, and swales. Ensure pipes are not clogged or cracked. Ensure catch basins are not clogged. Ensure swales have not eroded. Replace rip rap pipe outlet protection if necessary. Condition Acceptable Condition Not Acceptable Action Taken/Remarks (include date of repair if applicable): Maintenance to be performed semi-annually: 10 Check sediment accumulation in forebay and main basin. Remove sediment when sediment elevation has reached 3.87 in the forebay and 2.75 in the main pond. Condition Acceptable Condition Not Acceptable Action Taken/Remarks (include date of repair if applicable): 11 Check operability of gate valve. Condition Acceptable Condition Not Acceptable Action Taken/Remarks (include date of repair if applicable): General Remarks: OJATHE LPA GROUP of North Carolina, p.a. Transportation Consultants 5000 FALLS OF NEUSE ROAD, SUITE 304 ■ RALEIGH, NORTH CAROLINA 27609 ■ 919-954-1244 ■ FAX 919-954-1345 February 21, 2008 Mr. Bill Moore NCDENR, Division of Water Quality Washington Regional Office 943 Washington Square Mall Washington, North Carolina 27889 SGe RECEMED Re: Craven County Regional Airport FEB 2 5 2008 Drainage Improvements 1A' �p� App��11 Dear Bill: �tltlQ'17tfA�otJ Enclosed please find one copy of the plans for the above referenced project for your review. This project does not include the addition of any impervious area. Due to this, I do not think a Stormwater Management Permit will be required. The Drainage Improvements project is being completed to improve stormwater drainage in multiple locations at the Craven County Regional Airport. This project will consist of the re- grading of.two midfield areas, the re -grading of three ditches, and the installation of three new pipes. If you have any questions or need additional information, please do not hesitate to call. Sincerely, THE LPA GROUP o�ar'olina, p.a. ason L. Elliott, El Aviation Design Enclosures Member of THE LPA GROUP INCORPORATED ATLANTA ■ BATON ROUGE ■ CHARLOTTE ■ COLUMBIA ■ GREENSBORO ■ JACKSONVILLE KNOXVILLE ■ LITTLE ROCK ■ MOBILE ■ ORIANDO ■ RALEIGH ■ SARASOTA ■ TALLAHASSEE ■ TAMPA ■ WEST PALM BEACH WRZo State of North Carolina Department of Environment and Natural Resources Washington Regional Office James B. Hunt, Jr., Governor Wayne McDevitt, Secretary DIVISION OF WATER QUALITY March 19, 1998 Craven County Regional Airport Attn: Mr. John H. Price, Jr. 1501 Airport Road New Bern, NC 28560 Dear Mr. Price: Aea-WA NCDENR NaRry f/J1 D NFu11CV�gO. ExY�gwN[M u,O K R[SOuq [[5 Subject: Stormwater Permit No. SW7970812 New Terminal Project High Density Stormwater Project Craven County The Washington Regional Office received the completed Stormwater Application for the subject project on February 26, 1998. Staff review of the plans and specifications has determined that the project, as proposed, will comply with the Stormwater Regulations set forth in Title 15A NCAC 2H.1000. We are forwarding Permit No. SW7970812 dated March 19, 1998 to the Craven County Regional Airport Authority. This permit shall be effective from the date of issuance until March 19, 2008 and shall be subject to the conditions and limitations as specified therein. 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, P.O. Drawer 27447, Raleigh, NC 27611-7447. Unless such demands are made this permit shall be final and binding. 943 Washington Square Mall. Washington, North Carolina 27889 Telephone 919-946-6481 FAX 919-975-3716 An Equal Opportunity Affirmative Action Employer 6 Craven County Regional Airport March 19, 1998 Page Two If you have any questions, or need additional information concerning this matter, please contact Bill Moore at (919) 946- 6481, extension 264. Sincerely, Roger K. Thorpe Water Quality Supervisor Washington Regional Office cc: The LPA Group of NC Craven County Inspections ashington Regional office Central Files State Stormwater Management Systems Permit No. SW7270812 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 Craven County Regional Airport Authority Craven County FOR THE construction, operation and maintenance of stormwater management systems 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 for a wet detention pond to serve the new Craven Airport Terminal located near New Bern, NC. This permit shall be effective from the date of issuance until March 19, 2008 and shall be subject to the following specified conditions and limitations: I. DESIGN STANDARDS 1. 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 4 of this permit, the Project Data Sheet. 3. Approved plans and specifications for this project are incorporated by reference and are enforceable parts of the permit. DIVISION OF WATER QUALITY PROJECT DATA Project Name: Permit Number: Location: Applicant: Mailing Address: Application Date: Water Body Receiving Stormwater Runoff: Classification of Water Body: Total Site Area: Drainage Area for this pond system: Total Impervious Surface Allowed: Pond/Basin Depth: Required Storage Volume: Provided Storage Volume: Required Surface Area: Provided Surface Area: Craven County Regional Airport - Terminal SW7970812 Craven County Craven County Regional Airport Authority 1501 Airport Road New Bern, NC 28560 8/12/97; original 2/26/98; complete Scotts Creek SC 42.0 acres 26.0 acres 14.2 acres (for new terminal) 3.0 feet 94,380 cubic feet (based on 1 inch) 112,380 cubic feet 52,272 square feet 52,422 square feet Controlling Orifice: 4.0 inch orifice 4 4. No homeowner/lot owner/developer shall be allowed to fill in, alter, or pipe any vegetative practices (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. 5. The following items will require a modification to the permit: 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 of the project area. In addition, the Director may determine that other revisions to the project should require a modification to the permit. 6. 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. II. SCHEDULE OF COMPLIANCE 1. The permittee will comply with the following schedule for construction and maintenance of the stormwater management system. a. 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 surfaces except roads. b. During construction, erosion shall be kept to a minimum and any eroded areas of the system will be repaired immediately. 2. The facilities must be properly maintained and operated at all times. The approved Operation and Maintenance Plan must be followed in its entirety and maintenance must occur at the scheduled intervals. 3. The permittee shall at all times provide the operation and maintenance necessary to assure the permitted stormwater system functions at optimum efficiency including, but not limited to: 5 a. Semiannual scheduled inspections (every 6 months) b. Sediment removal C. Mowing and revegetation of side slopes d. Immediate repair of eroded areas e. Maintenance of side slopes in accordance with approved plans and specifications f. Debris removal and unclogging of outlet structure, orifice device and catch basins and piping. 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. 5. 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. 6. Upon completion of construction 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. Mail the Certification to the Washington Regional Office, 943 Washington Square Mall, Washington, North Carolina, 27889, attention Division of Water Quality. 7. A copy of the approved plans and specifications shall be maintained on file by the Permittee for a minimum of five years from the date of the completion of construction. III. GENERAL CONDITIONS 1. This permit is not transferable. In the event there is a desire for the facilities to change ownership, or there is a name change of the Permittee, a formal permit request must be submitted to the Division of Water Quality accompanied by an application fee, 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. 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 143-215.6(a) to 143-215.6(c). 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. 6 4. 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 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. Permit issued this the 19 th day of March, 1998. NORTH CAROLINA ENVIRONMENTAL MANAGEMENT COMMISSION �.-A. Preston Howard, Jr./, P.E., Director Division of Water Quality By Authority of the Environmental Management Commission Permit Number SW7970812 7 Craven County Regional Airport Authority New Terminal Project Craven County Stormwater Permit No. SW7970812 Designer's Certification , as a duly registered Professional Engineer in the State of North Carolina, having been authorized to observe (periodically/weekly/full time) the construction of the project, for (Project) (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. Signature Registration Number Date AUG - 6 2007 �) - I a?. 7 Permit No# Sta T) 1 os612— WET DETENTION BASIN OPERATION AND MAINTENANCE AGREEMENT Maintenance activities shall be performed as follows: 1. After every significant runoff producing rainfall event and at least monthly: a. Inspect the wet detention basin system for sediment accumulation, erosion, trash accumulation, vegetated cover, and general condition. b. Check and clear the orifice of any obstructions such that drawdown of the temporary pool occurs within 2 to 5 days as designed. 2. Repair eroded areas immediately, re -seed as necessary to maintain good vegetative cover, mow vegetative cover to maintain a maximum height of six. inches, and remove trash as needed. 3. Inspect and repair the collection system (i.e. catch basins, piping, swales, riprap, etc.) quarterly to maintain proper functioning. 4. Remove accumulated sediment from the wet detention basin system semi-annually or when depth is reduced to 75% of the original design depth (see diagram below). Removed sediment shall be disposed of in an appropriate manner and shall be handled in a manner that will not adversely impact water quality (i.e. stockpiling near a wet detention basin or stream, etc.). 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 When the permanent pool depth reads V Sediment Ren oval EL. - 87 75"n Bottom Ele ation `S.S --_ -- FOREBAY feet in the main pond, the sediment shall be removed. feet in the forebay, the sediment shall be removed. BASIN DIAGRAM (fill in the blanks) Permanent Pool Elevation = S. 0 Sediment Removal Elevation : ,2, 7y Bottom Elevation : 2, p MAIN POND Remove cattails and other indigenous wetland plants when they cover 50% of the basin surface. These plants shall be encouraged to grow along the vegetated shelf and forebay bean. 6. If the basin must be drained for an emergency or to perform maintenance, the flushing of sediment through the emergency drain shall be minimized to the maximum extent practical. . ;-ww 7. All components of the wet detention basin system shall be maintained in good working order. 8. Remove all trees and heavy woody vegetation from the basins and dike walls. I acknowledge and agree by my signature below that I am responsible for the performance of the seven 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. Print name: T o h1 B2AATGt,3 Title: 't)t2ec-ToCL Address: 2O0 16RMtNAL. �t2t�c' Nf;W'&EVJ,.n1C- .28542 Phone: a25A - (.36 - S 5q 1 Signature: �� VPL `� Date: 3 V �1-1 �Af -7 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. G-C� 42A , a Notary Public for the State of County of -C Lt ado hereby certify that personally appeared before me this _ZO_*'-�ay'of In 40 6'j and acknowledge the due execution of the forgoing wet detention basin maintenance requirements. Witness my hand and official seal, Notary Public My commission expires 31—c� - '4100 d PROOLCTAH�LryY5Mlb1ffi ifRNM�O.Iz.G�om Wu 01471. TO amPo Ero1L FREE H(6MS s THE LPA GROUP of North Carolina, p.a. P.O. Box 17736 RALEIGH, NORTH CAROLINA 27619 (919) 954.1244 FAX (919) 954.1345 WOgI[rmllspSM Im I ' JOB SHEET NO. OF CALCULATED BY DATE 11 I'L5 i91 CHECKED BY DATE L THE LPA GROUP of North Carolina, p.a. P.O. Box 17736 RALEIGH, NORTH CAROLINA 27619 (919) 954.1244 FAX (919) 954.1345 a SHEET NO. _ CALCULATED CHECKED BY. DATE 11--.".-1 gym ,'w' t } • Craven County Airport - Terminal Complex * Detention Pond ' 10 Year Design Storm # # ****************** SUMMARY OF ROUTING COMPUTATIONS ****************** Pond File: CR-POND .PND Inflow Hydrograph: CR-POND .HYD Outflow Hydrograph: OUT .HYD Starting Pond W.S. Elevation = 5.00 ft ***** Summary of Peak Outflow and Peak Elevation ***** Peak Inflow = 174.00 cfs Peak Outflow = 60.70 cfs Peak Elevation = 8.56 ft ***** Summary of Approximate Peak Storage ***** Initial Storage = 0.00 ac-ft Peak Storage From Storm = 4.84 ac-ft Total Storage in Pond = -------------- 4.84 ac-ft Warning: Inflow hydrograph truncated on left side. Peak Inflow = 174.00 cfs Peak Outflow = 60.70 cfs Peak Elevation = 8.56 ft 0 20 40 60 80 100 120 140 I 11.3 -Ix * Ix + 11.4 -1x Ix 11.5 -Ix x 11.6 -Ix x + 11.7 -Ix x + 11.8 -x Ix + 11.9 -Ix x + 12.0 -Ix x + 12.1 -I x x 12.2 -I x x 12.3 -1 x x + 12.4 -I * x * x 12.5 -I * x * x 12.6 -I * x * x 12.7 -I * x I * x 12.8 -I * x I x 12.9 -I * x x 13.0 -I x * x 13.1 -1 * x I * x 13.2 -1 x I TIME (hrs) * File: CR-POND .HYD Qmax = 174.0 cfs x File: OUT .HYD Qmax = 60.7 cfs EXECUTED: 11-25-1997 11:48:43 Flow (cfs) 160 180 200 220 -1----- I ----- I ----- I- + + � i # * Craven County Airport - Terminal Complex + * Detention Pond * 25 Year Event # # *********++++**+++ SUMMARY OF ROUTING COMPUTATIONS *****+*****+**+**+ Pond File: CR-POND .PND Inflow Hydrograph: CR-POND .HYD Outflow Hydrograph: OUT .HYD Starting Pond W.S. Elevation = 5.00 ft ***** Summary of Peak Outflow and Peak Elevation ***** Peak Inflow = 205.00 cfs Peak Outflow = 89.38 cfs Peak Elevation = 8.81 ft ***** Summary of Approximate Peak Storage ***** l Initial Storage = 0.00 ac-ft Peak Storage From Storm = 5.24 ac-ft --------------- Total Storage in Pond = 5.24 ac-ft Peak Inflow = 205.00 cfs Peak Outflow = 89.38 cfs Peak Elevation = 8.81 ft 0 25 50 75 100 125 I 11.3 -1x Ix + 11.4 -Ix * Ix + 11.5 -Ix Ix 11.6 -1x Ix + 11.7 -Ix Ix + 11.8 -Ix Ix 11.9 -Ix Ix 12.0 -Ix x 12.1 -I x I x 12.2 -I x x 12.3 -I x I * x 12.4 -I * x * x 12.5 -1 * x I * x 12.6 -I * x x 12.7 - * x * x 12.8 -I x * x 12.9 -I * x * x 13.0 -I * x * x 13.1 -I * x * x 13.2 -1 x I TIME (hrs) EXECUTED: 11-25-1997 14:02:39 Flow (cfs) 150 175 200 225 250 275 -1----- I ----- I ----- I ----- I ----- I- * File: CR-POND .HYD Qmax = 205.0 cfs x File: OUT .HYD Qmax = 69.4 cfs I xx#x#+x#xxx+x++#++++++axx+#x+++a#ax++#+ax#x#++ # # + Craven County Airport - Terminal Complex + Detention Pond + * 10 Year Design Storm + Inflow Hydrograph: CR-POND .HYD Rating Table file: CR-POND .PND ----INITIAL CONDITIONS ---- Elevation = 5.00 ft Outflow = 0.00 cfs Storage = 0.00 ac-ft GIVEN POND DATA ------------------------------ IELEVATIONI OUTFLOW I STORAGE I I (ft) I (cfs) --------- I (ac-ft) I ---------- I--------- I 1 5.00 1 0.0 I I 1 0.0001 1 5.10 1 0.0 1 0.1201 1 5.20 1 0.0 1 0.2401 1 5.30 1 0.0 1 0.3621 1 5.40 1 0.0 1 0.4841 1 5.50 1 0.0 1 0.6081 1 5.60 1 0.0 1 0.7321 1 5.70 1 0.0 1 0.8581 1 5.80 1 0.0 1 0.9841 1 5.90 1 0.0 1 1.1121 1 6.00 1 0.0 1 1.2411 1 6.10 1 0.0 1 1.3701 1 6.20 1 0.0 1 1.5011 1 6.30 1 0.0 1 1.6321 1 6.40 1 0.0 1 1.7641 1 6.50 1 0.0 1 1.8971 1 6.60 1 0.0 1 2.0311 1 6.70 1 0.0 1 2.1661 1 6.80 1 0.0 1 2.3021 1 6.90 1 0.0 1 2.4391 1 7.00 1 0.0 1 2.5761 1 7.10 1 0.9 1 2.7151 1 7.20 1 2.7 1 2.8541 1 7.30 1 4.9 1 2.9951 1 7.40 1 7.6 1 3.1361 1 7.50 1 10.6 1 3.2781 1 7.60 1 13.9 1 3.4211 1 7.70 1 17.6 1 3.5661 1 7.80 1 21.5 1 3.7111 1 7.90 1 21.9 1 3.8571 1 8.00 1 ------------------------------ 22.1 1 4.0041 INTERMEDIATE ROUTING COMPUTATIONS -------------------------- 2S/t I 2S/t + 0 (cfs) ------------ I -------------I (cfs) 0.0 0.0 1 28.9 I 28.9 1 58.1 1 58.1 1 87.5 1 87.5 1 117.1 117.1 I 147.0 147.0 177.2 177.2 207.6 207.6 238.2 1 238.2 1 269.1 1 269.1 1 300.2 1 300.2 1 331.6 1 331.6 1 363.1 1 363.1 1 394.9 394.9 426.9 426.9 I 459.1 459.1 I 491.6 1 491.6 1 524.2 524.2 557.1 I 557.1 590.2 I 590.2 623.5 1 623.5 1 657.0 657.9 1 690.7 693.4 1 724.7 729.6 1 758.9 766.5 793.3 803.9 828.0 I 841.9 862.9 I 880.5 898.0 919.5 933.3 955.2 968.9 -------------------------- 991.0 I GIVEN POND DATA ELEVATIONI OUTFLOW I STORAGE I (ft) I (cfs) --------- I (ac-ft) I I--------- 1 8.10 I 1 25.2 I ---------- 1 4.1521 I 1 8.20 1 30.6 1 4.3011 1 8.30 1 37.6 1 4.4521 1 8.40 1 45.7 1 4.6031 1 8.50 1 54.9 1 4.7561 1 8.60 1 65.1 1 4.9101 1 8.70 1 76.1 1 5.0651 1 8.80 1 87.9 1 5.2221 1 8.90 1 100.4 1 5.3791 1 9.00 ------------------------------ 1 89.4 1 5.5381 INTERMEDIATE ROUTING COMPUTATIONS I 2S/t I 2S/t + 0 1 (cfs) ------------ I (cfs) -------------I 1004.7 1029.9 1 1040.9 1071.5 I 1077.3 1 1114.9 1114.0 1 1159.7 1 1150.9 1 1205.8 1 1188.2 1 1253.3 1 1225.8 1301.9 I 1 1263.6 1351.5 1 1301.8 1402.2 1340.2 -------------------------- 1429.6 Time increment (t) = 0.100 hrs. Pond File: Inflow Hydrograph: Outflow Hydrograph: INFLOW HYDROGRAPH I TIME I INFLOW I (hrs) I (cfs) I 1 11.000 1 4.001 1 11.100 1 5.001 1 11.200 1 5.001 1 11.300 1 6.001 1 11.400 1 8.001 1 11.500 1 10.001 11.600 1 12.001 11.700 1 26.001 11.800 1 41.001 11.900 1 55.001 12.000 1 106.001 12.100 1 174.001 12.200 1 147.001 12.300 1 82.001 12.400 1 50.001 12.500 1 37.001 12.600 1 27.001 12.700 1 21.001 12.800 1 18.001 12.900 1 16.001 13.000 1 15.001 13.100 1 14.001 13.200 1 14.001 13.300 1 13.001 13.400 1 12.001 13.500 I 12.001 13.600 11.001 13.700 1 11.001 13.800 1 11.001 13.900 1 10.001 14.000 1 9.001 14.100 1 8.001 14.200 1 8.001 14.300 1 7.001 14.400 1 6.001 14.500 1 6.001 14.600 1 5.001 14.700 1 5.001 14.800 1 5.001 14.900 1 5.001 15.000 1 5.001 15.100 1 5.001 15.200 1 5.001 15.300 1 5.001 15.400 ------------------ 1 5.001 CR-POND .PND CR-POND .HYD OUT HYD ROUTING COMPUTATIONS I1+I2 I 2S/t - 0 1 2S/t + O I OUTFLOW IELEVATIONI (cfs) I - -------------------- (cfs) I I (cfs) ----------- I (cfs) I (ft) I ----- 0.0 1 0.01 I --------- 0.00 ---------I 5.00 I 9.0 1 9.0 9.01 0.00 5.03 1 10.0 19.0 1 19.01 0.00 5.07 1 11.0 30.0 1 30.01 0.00 5.10 1 14.0 44.0 1 44.01 0.00 1 5.15 1 18.0 62.0 I 62.01 0.00 1 5.21 1 22.0 84.0 84.01 0.00 1 5.29 1 38.0 1 122.0 122.01 0.00 1 5.42 1 67.0 1 189.0 1 189.01 0.00 1 5.64 1 96.0 1 285.0 1 .285.01 0.00 1 5.95 1 161.0 1 446.0 1 446.01 0.00 1 6.46 1 280.0 1 716.6 1 726.01 4.68 1 7.29 1 321.0 1 985.2 I 1037.61 26.20 1 8.12 1 229.0 1 1100.8 1214.21 56.70 1 8.52 1 132.0 1 1111.4 1 1232.81 60.70 1 8.56 1 87.0 1 1091.6 I 1198.41 53.42 1 8.48 1 64.0 1 1065.7 1 1155.61 44.96 1 8.39 1 48.0 1 1036.9 1 1113.71 37.40 1 8.30 1 39.0 1 1014.6 1 1077.91 31.63 1 8.21 1 34.0 1 993.3 I 1048.61 27.63 1 8.14 1 31.0 974.8 1 1024.31 24.75 1 8.09 1 29.0 957.6 1 1003.81 23.12 1 8.03 1 28.0 1 941.5 1 985.61 22.07 1 7.98 I 27.0 1 924.5 1 968.51 21.97 7.94 25.0 1 905.8 1 949.51 21.84 1 7.88 24.0 1 886.6 1 929.81 21.62 1 7.83 1 23.0 I 868.6 1 909.61 20.51 1 7.77 1 22.0 853.4 1 890.61 18.61 1 7.73 1 22.0 841.1 1 875.41 17.11 1 7.69 1 21.0 1 830.5 1 862.11 15.84 1 7.65 1 19.0 1 820.2 1 849.51 14.63 1 7.62 1 17.0 1 810.2 1 837.21 13.49 1 7.59 1 16.0 1 801.1 1 826.21 12.54 1 7.56 1 15.0 792.8 1 816.11 11.66 1 7.53 1 13.0 784.3 1 805.81 10.76 1 7.50 1 12.0 1 776.3 1 796.31 9.99 1 7.48 1 11.0 1 768.8 1 787.31 9.27 1 7.46 1 10.0 1 761.6 1 778.81 8.58 1 7.43 1 10.0 I 755.6 1 771.61 8.01 1 7.41 1 10.0 750.5 1 765.61 7.53 1 7.40 1 10.0 1 746.2 1 760.51 7.16 1 7.38 1 10.0 1 742.5 1 756.21 6.85 1 7.37 1 10.0 1 739.4 1 752.51 6.58 1 7.36 1 10.0 1 736.7 1 749.41 6.35 1 7.35 1 10.0 ----------------------------------------------------- 1 734.4 1 746.71 6.15 1 7.35 1 Pond File: Inflow Hydrograph: Outflow Hydrograph: INFLOW HYDROGRAPH ------------------ TIME I INFLOW I (hrs) -------- I (Cfs) --------- I I 1 15.500 I 1 5.001 I 1 15.600 1 5.001 1 15.700 1 5.001 1 15.800 1 4.001 1 15.900 1 4.001 1 16.000 1 4.001 1 16.100 1 4.001 1 16.200 1 4.001 16.300 1 3.001 16.400 1 3.001 16.500 1 3.001 16.600 1 3.001 16.700 1 3.001 16.800 1 3.001 16.900 1 3.001 17.000 1 3.001 17.100 1 3.001 17.200 1 3.001 17.300 1 3.001 17.400 1 3.001 17.500 1 3.001 17.600 1 3.001 17.700 1 3.001 17.800 3.001 17.900 1 3.001 18.000 1 3.001 18.100 1 3.001 18.200 1 3.001 18.300 1 3.001 18.400 1 3.001 18.500 1 3.001 18.600 1 3.001 18.700 1 3.001 18.800 1 3.001 18.900 1 3.001 19.000 1 3.001 19.100 1 3.001 19.200 1 3.001 19.300 1 3.001 19.400 1 3.001 19.500 1 3.001 19.600 1 3.001 19.700 1 3.001 19.800 1 3.001 19.900 1 3.001 20.000 ------------------ 1 3.001 CR-POND .PND CR-POND .HYD OUT HYD ROUTING COMPUTATIONS ------------------------------------------------------ I I1+I2 I 2S/t - 0 1 2S/t + 0 1 OUTFLOW IELEVATIONI I (Cfs) --------- I I (Cfs) ------------ I (Cfs) ----------- I (Cfs) I (ft) 10.0 1 732.4 744.41 I --------- 5.98 I ---------I 1 7.34 1 I 10.0 1 730.7 1 742.41 5.84 1 7.33 1 1 10.0 1 729.3 1 740.71 5.71 1 7.33 1 9.0 1 727.2 I 738.31 5.54 1 7.32 1 8.0 1 724.6 735.21 5.31 1 7.32 1 I 8.0 1 722.4 1 732.61 5.12 1 7.31 1 1 8.0 1 720.5 1 730.41 4.96 1 7.30 1 1 8.0 1 718.8 1 728.51 4.83 1 7.30 1 1 7.0 1 716.5 725.81 4.67 1 7.29 1 1 6.0 1 713.5 722.51 4.47 1 7.28 1 1 6.0 1 710.9 719.51 4.29 1 7.27 1 1 6.0 1 708.7 1 716.91 4.13 1 7.27 1 1 6.0 1 706.7 1 714.71 3.99 1 7.26 1 1 6.0 1 705.0 1 712.71 3.87 1 7.25 1 1 6.0 1 703.4 1 711.01 3.77 1 7.25 1 1 6.0 1 702.1 1 709.41 3.67 1 7.24 1 1 6.0 1 700.9 1 708.11 3.59 1 7.24 1 1 6.0 1 699.9 1 706.91 3.52 1 7.24 1 1 6.0 1 698.9 1 705.91 3.46 1 7.23 1 1 6.0 1 698.1 1 704.91 3.40 1 7.23 1 1 6.0 1 697.4 I 704.11 3.35 1 7.23 1 1 6.0 1 696.8 703.41 3.31 1 7.23 1 1 6.0 1 696.3 1 702.81 3.27 1 7.23 1 1 6.0 1 695.8 1 702.31 3.24 1 7.22 1 1 6.0 1 695.4 1 701.81 3.21 1 7.22 1 6.0 1 695.0 1 701.41 3.18 1 7.22 1 6.0 694.7 1 701.01 3.16 1 7.22 1 6.0 694.4 1 700.71 3.14 1 7.22 1 I 6.0 I 694.2 1 700.41 3.12 1 7.22 1 I 6.0 1 693.9 1 700.21 3.11 1 7.22 1 1 6.0 1 693.7 1 699.91 3.10 1 7.22 1 6.0 1 693.6 1 699.71 3.08 1 7.22 1 6.0 1 693.4 1 699.61 3.07 1 7.22 1 6.0 1 693.3 1 699.41 3.07 1 7.22 1 1 6.0 1 693.2 1 699.31 3.06 1 7.22 1 1 6.0 1 693.1 1 699.21 3.05 1 7.22 1 1 6.0 1 693.0 1 699.11 3.04 1 7.22 1 1 6.0 1 692.9 1 699.01 3.04 1 7.22 1 1 6.0 1 692.9 1 698.91 3.03 1 7.22 1 1 6.0 1 692.8 1 698.91 3.03 1 7.21 1 I 6.0 1 692.7 1 698.81 3.03 1 7.21 1 6.0 1 692.7 1 698.71 3.02 1 7.21 1 6.0 1 692.7 1 698.71 3.02 1 7.21 1 1 6.0 1 692.6 I 698.71 3.02 1 7.21 1 1 6.0 1 692.6 1 698.61 3.02 1 7.21 1 1 6.0 ------------------------------------------------------ 1 692.6 1 698.61 3.01 1 7.21 1 Pond File: Inflow Hydrograph: Outflow Hydrograph: I TIME I INFLOW I I (hrs) I (cfs) I I-------- 1 20.100 I 1 --------- 3.001 I 20.200 1 3.001 120.300 I 3.001 120.400 I 3.001 120.500 I 3.001 1 20.600 I 3.001 120.700 I 3.001 1 20.800 I 3.001 1 20.900 I 3.001 121.000 I 3.001 121.100 1 3.001 1 21.200 1 3.001 1 21.300 I 3.001 1 21.400 1 3.001 1 21.500 I 3.001 121.600 1 3.001 121.700 I 3.001 1 21.800 I 3.001 21.900 1 3.001 22.000 I 3.001 22.100 I 3.001 22.200 I 3.001 22.300 I 3.001 22.400 1 3.001 22.500 1 3.001 22.600 1 3.001 22.700 I 2.001 22.800 I 2.001 22.900 I 2.001 23.000 I 2.001 23.100 I 2.001 23.200 1 2.001 23.300 I 2.001 23.400 1 2.001 23.500 I 2.001 23.600 I 2.001 23.700 1 2.001 23.800 1 2.001 23.900 1 2.001 24.000 1 2.001 24.100 I 1.001 24.200 I 1.001 24.300 I 1.001 24.400 I 1.001 24.500 I 1.001 24.600 ------------------ I 1.001 CR-POND .PND CR-POND .HYD OUT HYD ROUTING COMPUTATIONS ------------------------------------------------------ I I1+I2 I 2S/t - 0 I 2S/t + 0 1 OUTFLOW IELEVATIONI I (cfs) I I--------- I (cfs) ------------ I I (cfs) ----------- I (cfs) --------- I (ft) I 1 6.0 1 692.5 1 698.61 I 3.01 I --------- 1 7.21 I 1 1 6.0 1 692.5 1 698.51 3.01 1 7.21 1 1 6.0 1 692.5 1 698.51 3.01 1 7.21 1 1 6.0 1 692.5 1 698.51 3.01 1 7.21 1 1 6.0 1 692.5 1 698.51 3.01 1 7.21 1 1 6.0 1 692.4 1 698.51 3.01 1 7.21 1 6.0 692.4 1 698.41 3.01 1 7.21 I I 6.0 692.4 1 698.41 3.00 1 7.21 1 6.0 692.4 1 698.41 3.00 1 7.21 1 6.0 692.4 1 .698.41 3.00 1 7.21 1 6.0 1 692.4 1 698.41 3.00 1 7.21 1 6.0 1 692.4 1 698.41 3.00 1 7.21 1 1 6.0 1 692.4 1 698.41 3.00 1 7.21 1 6.0 1 692.4 1 698.41 3.00 1 7.21 1 6.0 1 692.4 1 698.41 3.00 1 7.21 1 6.0 1 692.4 1 698.41 3.00 1 7.21 1 6.0 1 692.4 1 698.41 3.00 1 7.21 1 6.0 1 692.4 1 698.41 3.00 1 7.21 1 6.0 692.4 1 698.41 3.00 1 7.21 1 6.0 692.4 1 698.41 3.00 1 7.21 1 6.0 692.4 1 698.41 3.00 1 7.21 1 6.0 1 692.4 1 698.41 3.00 1 7.21 1 6.0 1 692.4 1 698.41 3.00 1 7.21 1 6.0 1 692.4 1 698.41 3.00 1 7.21 1 6.0 1 692.4 1 698.41 3.00 1, 7.21 1 6.0 1 692.4 1 698.41 3.00 1 7.21 1 5.0 1 691.5 1 697.41 2.94 1 7.21 1 4.0 1 689.8 1 695.51 2.83 1 7.21 1 4.0 I 688.4 1 693.81 2.72 1 7.20 1 4.0 I 687.1 1 692.41 2.65 1 7.20 1 4.0 685.9 1 691.11 2.58 1 7.19 1 4.0 1 684.9 1 689.91 2.52 1 7.19 1 4.0 1 683.9 1 688.91 2.47 1 7.19 1 4.0 1 683.1 1 687.91 2.42 1 7.18 1 4.0 1 682.3 1 687.11 2.38 1 7.18 1 4.0 1 681.7 1 686.31 2.34 1 7.18 1 4.0 1 681.0 1 685.71 2.31 1 7.18 1 4.0 1 680.5 1 685.01 2.28 1 7.18 1 4.0 1 680.0 1 684.51 2.25 1 7.17 1 4.0 1 679.6 1 684.01 2.22 1 7.17 1 3.0 1 678.3 1 682.61 2.15 1 7.17 1 2.0 1 676.2 1 680.31 2.03 1 7.16 1 2.0 1 674.3 1 678.21 1.93 1 7.16 1 2.0 1 672.7 1 676.31 1.83 1 7.15 1 2.0 1 671.2 1 674.71 1.75 1 7.15 1 2.0 1 ------------------------------------------------------ 669.8 1 673.21 1.67 1 7.14 1 Pond File: Inflow Hydrograph: Outflow Hydrograph: INFLOW HYDROGRAPH I TIME I INFLOW I I (hrs) I (cfs) I I-------- 1 24.700 I 1 --------- 1.001 I 1 24.800 1 1.001 1 24.900 1 1.001 1 25.000 1 1.001 1 25.100 1 1.001 1 25.200 1 1.001 1 25.300 1 1.001 1 25.400 1 0.001 1 25.500 1 0.001 1 25.600 1 0.001 1 25.700 1 0.001 1 25.800 1 0.001 1 25.900 ----------------- 1 0.001 CR-POND .PND CR-POND .HYD OUT HYD ROUTING COMPUTATIONS ------------------------- I I1+I2 I 2S/t - 0 1 1 (cfs) I --------- (cfs) I 1------------I-- 2.0 668.6 2.0 667.5 1 2.0 1 666.5 1 2.0 I 665.7 1 2.0 664.9 1 1 2.0 1 664.2 1 1 2.0 1 663.5 1 1 1.0 1 662.0 1 1 0.0 1 659.8 1 1 0.0 1 657.8 1 0.0 656.0 0.0 I 654.3 I 0.0 I ------------------------- 652.7 1 ----------------------------- 2S/t + 0 1 OUTFLOW ELEVATIONI (cfs) I --------- 1--------- (cfs) I (ft) --------- I 671.81 I 1.61 1 7.14 1 670.61 1.54 1 7.14 1 669.51 1.49 1 7.13 1 668.51 1.44 1 7.13 1 667.71 1.40 1 7.13 1 666.91 1.36 1 7.13 1 666.21 1.32 1 7.12 1 664.51 1.24 1 7.12 1 662.01 1.11 1 7.11 1 659.81 1.00 1 7.11 I 657.81 0.90 1 7.10 1 656.01 0.85 1 7.09 1 654.31 ----------------------------- 0.81 1 7.09 1 ****************** SUMMARY OF ROUTING COMPUTATIONS ****************** Pond File: CR-POND .PND Inflow Hydrograph: CR-POND .HYD Outflow Hydrograph: OUT .HYD Starting Pond W.S. Elevation = 5.00 ft ***** Summary of Peak Outflow and Peak Elevation ***** Peak Inflow = 174.00 cfs Peak Outflow = 60.70 cfs Peak Elevation = 8.56 ft ***** Summary of Approximate Peak Storage ***** Initial Storage = 0.00 ac-ft Peak Storage From Storm = 4.84 ac-ft Total Storage in Pond = --------------- 4.84 ac-ft Warning: Inflow hydrograph truncated on left side. Peak Inflow = 174.00 cfs Peak Outflow = 60.70 cfs Peak Elevation = 8.56 ft EXECUTED: 11-25-1997 11:48:43 Flow (cfs) 0 20 40 60 80 100 120 140 160 180 200 220 ------- I ----- I ----- I ----- I ----- I ----- I ----- I ----- I ----- I ----- I ----- I- 1 11.3 -Ix Ix + 11.4 -Ix Ix + 11.5 -Ix Ix + 11.6 -1x Ix + 11.7 -1x Ix 11.8 -Ix Ix + 11.9 -Ix Ix + 12.0 -lx x + 12.1 -I x x + 12.2 -I x I x 12.3 -I x I x 12.4 -I * x * x 12.5 -I * x I * x 12.6 -I * x x 12.7 -I * x I x 12.8 -I x x 12.9 -I * x * x 13.0 -I * x I * x 13.1 -I * x * x 13.2 -1 * x I TIME (hrs) * File: CR-POND .HYD Qmax = 174.0 cfs x File: OUT .HYD Qmax = 60.7 cfs I Outlet Structure File: CR-POND .STR I POND-2 Version: 5.17 SIN: Date Executed: Time Executed: ++++++++++++++++++++++++++++++++++++++++ Craven County Airport - Terminal Complex Detention Pond ***** COMPOSITE OUTFLOW SUMMARY **** Elevation (ft) Q (cfs) Contributing Structures 5.00 0.0 5.10 0.0 5.20 0.0 5.30 0.0 5.40 0.0 5.50 0.0 5.60 0.0 5.70 0.0 5.80 0.0 5.90 0.0 6.00 0.0 6.10 0.0 6.20 0.0 6.30 0.0 6.40 0.0 6.50 0.0 6.60 0.0 6.70 0.0 6.80 0.0 6.90 0.0 7.00 0.0 1 7.10 0.9 1 7.20 2.7 1 7.30 4.9 1 7.40 7.6 1 7.50 10.6 1 7.60 13.9 1 7.70 17.6 1 7.80 21.5 1 7.90 21.9 2 8.00 22.1 2 +3 8.10 25.2 2 +3 8.20 30.6 2 +3 8.30 37.6 2 +3 8.40 45.7 2 +3 8.50 54.9 2 +3 8.60 65.1 2 +3 8.70 76.1 2 +3 8.80 87.9 2 +3 8.90 100.4 2 +3 9.00 89.4 3 ++++++++++++++++++++++++++++++++++++++++ Craven County Airport - Terminal Complex Detention Pond Outlet Structure File: CR-POND .STR Planimeter Input File: CR-POND .VOL Rating Table Output File: CR-POND .PND Min. Elev.(ft) = 5 Max. Elev.(ft) = 9 Incr.(ft) _ .1 Additional elevations (ft) to be included in table: + + a + + + + + + + a a + + + a + a + + + + a + + + +++++++++++++++++++aaa++++++++++aaa+++++++++aa SYSTEM CONNECTIVITY Structure No. INLET BOX 1 CULVERT-CR 2 ? WEIR-VR 3 + Q Table Q Table -> 1 1 -> A A -> B Outflow rating table summary was stored in file: CR-POND .PND Outlet Structure File: CR-POND .STR »»» Structure No. 1 ««« (Input Data) INLET BOX Weir & Orifice defined by length and area E1 elev.(ft)? 7.0 E2 elev.(ft)? 9 Crest elev.(ft)? 7.0 Weir length (ft)? 10 Weir coefficient? 3.0 Orifice area (sq.ft)? 6.67 Orifice coefficient? .6 Start transition elev.(ft) @ ? 7.33 Transition height (ft)? .33333 nj ++++++++++++++++++++++++++++++++++++++++ Craven County Airport - Terminal Complex Detention Pond ++++++++++++++++++++++++++++++++++++++++ »»» Structure No. 2 ««« (Input Data) CULVERT-CR Circular Culvert (With Inlet Control) E1 elev.(ft)? 7.0 E2 elev.(ft)? 9.0 Diam. (ft)? 1.5 Inv. el.(ft)? 2 . Slope (ft/ft)? .005 T1 ratio? T2 ratio? K Coeff.? .0045 M Coeff.? 2.0 c Coeff.? .0317 Y Coeff.? .69 Form 1 or 2? 1 Slope factor? -0.5 »»» Structure No. 3 ««« (Input Data) WEIR-VR Weir - Vertical Rectangular E1 elev.(ft)? 8 E2 elev.(ft)? 10 Weir coefficient? 3.0 Weir elev.(ft)? 8 Length (ft)? -30 Contracted/Suppressed (C/S)? C ***** INLET CONTROL ASSUMED ***** Elevation (ft) Q (cfs) Computation Messages 5.00 0.0 E < Inv.E1.= 7 5.10 0.0 E < E1=7.0 5.20 0.0 E < E1=7.0 5.30 0.0 E < E1=7.0 5.40 0.0 E < E1=7.0 5.50 0.0 E < E1=7.0 5.60 0.0 E < E1=7.0 5.70 0.0 E < E1=7.0 5.80 0.0 E < E1=7.0 5.90 0.0 E < E1=7.0 6.00 0.0 E < E1=7.0 6.10 0.0 E < E1=7.0 6.20 0.0 E < E1=7.0 6.30 0.0 E < E1=7.0 6.40 0.0 E < E1=7.0 6.50 0.0 E < E1=7.0 6.60 0.0 E < E1=7.0 6.70 0.0 E < E1=7.0 6.80 0.0 E < E1=7.0 6.90 0.0 E < E1=7.0 7.00 0.0 Weir: H =0.0 7.10 0.9 Weir: H =.1 7.20 2.7 Weir: H =.2 7.30 4.9 Weir: H =.3 7.40 7.6 Weir: H =.4 7.50 10.6 Weir: H =.5 7.60 13.9 Weir: H =.6 7.70 17.6 Weir: H =.7 7.80 21.5 Weir: H =.8 7.90 25.6 Weir: H =.9 8.00 30.0 Weir: H =1.0 8.10 33.7 Orifice: H =1.1 8.20 35.2 Orifice: H =1.2 8.30 36.6 Orifice: H =1.3 8.40 38.0 Orifice: H =1.4 8.50 39.3 Orifice: H =1.5 8.60 40.6 Orifice: H =1.6 8.70 41.9 Orifice:• H =1.7 8.80 43.1 Orifice: H =1.8 8.90 44.3 Orifice: H =1.9 9.00 0.0 E = or > E2=9 Weir Cw = 3 Weir length = 10 ft Orifice Cc = .6 Orifice area = 6.67 sq.ft. Q (cfs) _ (Cw * L * H**1.5) or (Cc * A * sgr(2*g*H)) No transition used, transition zone ends below 8.07053 ft Weir equation = Orifice equation @ elev.= 8.07053 ft ++++++++++++++++++++++++++++++++++++++++ Craven County Airport - Terminal Complex Detention Pond ++++++++++++++++++++++++++++++++++++++++ Outflow Rating Table for Structure #2 CULVERT-CR Circular Culvert (With Inlet Control) ***** INLET CONTROL ASSUMED ***** Elevation (ft) Q (cfs) Computation Messages 5.00 0.0 E < E1=7.0 5.10 0.0 E < E1=7.0 5.20 0.0 E < E1=7.0 5.30 0.0 E < E1=7.0 5.40 0.0 E < E1=7.0 5.50 0.0 E < E1=7.0 5.60 0.0 E < E1=7.0 5.70 0.0 E < E1=7.0 5.60 0.0 E < E1=7.0 5.90 0.0 E < E1=7.0 6.00 0.0 E < E1=7.0 6.10 0.0 E < E1=7.0 6.20 0.0 E < E1=7.0 6.30 0.0 E < E1=7.0 6.40 0.0 E < E1=7.0 6.50 0.0 E < E1=7.0 6.60 0.0 E < E1=7.0 6.70 0.0 E < E1=7.0 6.80 0.0 E < E1=7.0 6.90 0.0 E < E1=7.0 7.00 19.8 Submerged: HW =5.0 7.10 20.0 Submerged: HW =5.1 7.20 20.3 Submerged: HW =5.2 7.30 20.5 Submerged: HW =5.3 7.40 20.7 Submerged: HW =5.4 7.50 21.0 Submerged: HW =5.5 7.60 21.2 Submerged: HW =5.6 7.70 21.5 Submerged: HW =5.7 7.80 21.7 Submerged: HW =5.8 7.90 21.9 Submerged: HW =5.9 8.00 22.1 Submerged: HW =6.0 8.10 22.4 Submerged: HW =6.1 8.20 22.6 Submerged: HW =6.2 8.30 22.8 Submerged: HW =6.3 8.40 23.0 Submerged: HW =6.4 8.50 23.2 Submerged: HW =6.5 8.60 23.4 Submerged: HW =6.6 8.70 23.7 Submerged: HW =6.7 8.80 23.8 Submerged: HW =6.8 8.90 24.0 Submerged: HW =6.9 9.00 0.0 E = or > E2=9.0 Craven County Airport - Terminal Complex Detention Pond ***************;******.***************** Outflow Rating Table for Structure #3 WEIR-VR Weir - Vertical Rectangular ***** INLET CONTROL ASSUMED ***** Elevation (ft) Q (cfs) Computation Messages 5.00 0.0 E < Inv.E1.= 8 5.10 0.0 E < Inv.E1.= 8 5.20 0.0 E < Inv.E1.= 8 5.30 0.0 E < Inv.E1.= 8 5.40 0.0 E < Inv.E1.= 8 5.50 0.0 E < Inv.E1.= 8 5.60 0.0 E < Inv.E1.= 8 5.70 0.0 E < Inv.E1.= 8 5.80 0.0 E < Inv.E1.= 8 5.90 0.0 E < Inv.E1.= 8 6.00 0.0 E < Inv.E1.= 8 6.10 0.0 E < Inv.E1.= 8 6.20 0.0 E < Inv.E1.= 8 6.30 0.0 E < Inv.E1.= 8 6.40 0.0 E < Inv.E1.= 8 6.50 0.0 E < Inv.E1.= 8 6.60 0.0 E < Inv.E1.= 8 6.70 0.0 E < Inv.E1.= 8 6.80 0.0 E < Inv.E1.= 8 6.90 0.0 E < Inv.E1.= 8 7.00 0.0 E < Inv.E1.= 8 7.10 0.0 E < Inv.E1.= 8 7.20 0.0 E < Inv.E1.= 8 7.30 0.0 E < Inv.E1.= 8 7.40 0.0 E < Inv.E1.= 8 7.50 0.0 E < Inv.El.= 8 7.60 0.0 E < Inv.E1.= 8 7.70 0.0 E < Inv.El.= 8 7.80 0.0 E < Inv.E1.= 8 7.90 0.0 E < Inv.E1.= 8 8.00 0.0 H =0.0 8.10 2.8 H =.1 8.20 8.0 H =.2 8.30 14.8 H =.3 8.40 22.7 H =.4 8.50 31.7 H =.5 8.60 41.7 H =.6 8.70 52.5 H =.7 8.80 64.1 H =.8 8.90 76.4 H =.9 9.00 69.4 H =1.0 Craven County Airport - Terminal Complex Detention Pond Outflow Rating Table A Table A = 1 ? 2 Elevation (ft) Q (cfs) Contributing Structures 5.00 0.0 - 5.10 0.0 - 5.20 0.0 - 5.30 0.0 - 5.40 0.0 - 5.50 0.0 - 5.60 0.0 - 5.70 0.0 - 5.80 0.0 - 5.90 0.0 - 6.00 0.0 - 6.10 0.0 - 6.20 0.0 - 6.30 0.0 - 6.40 0.0 - 6.50 0.0 - 6.60 0.0 - 6.70 0.0 - 6.80 0.0 - 6.90 0.0 - 7.00 0.0 1 7.10 0.9 1 7.20 2.7 1 7.30 4.9 1 7.40 7.6 1 7.50 10.6 1 7.60 13.9 1 7.70 17.6 1 7.80 21.5 1 7.90 21.9 2 8.00 22.1 2 8.10 22.4 2 8.20 22.6 2 8.30 22.8 2 8.40 23.0 2 8.50 23.2 2 8.60 23.4 2 8.70 23.7 2 8.80 23.8 2 8.90 24.0 2 9.00 0.0 - Outflow Rating Table B Table B = A + 3 Elevation (ft) Q (cfs) Contributing Structures 5.00 0.0 - 5.10 0.0 - 5.20 0.0 - 5.30 0.0 - 5.40 0.0 - 5.50 0.0 - 5.60 0.0 - 5.70 0.0 - 5.80 0.0 - 5.90 0.0 - 6.00 0.0 - 6.10 0.0 - 6.20 0.0 - 6.30 0.0 - 6.40 0.0 - 6.50 0.0 - 6.60 0.0 - 6.70 0.0 - 6.80 0.0 - 6.90 0.0 - 7.00 0.0 1 ( 7.10 0.9 1 7.20 2.7 1 7.30 4.9 1 7.40 7.6 1 7.50 10.6 1 7.60 13.9 1 7.70 17.6 1 7.80 21.5 1 7.90 21.9 2 8.00 22.1 2 +3 8.10 25.2 2 +3 8.20 30.6 2 +3 8.30 37.6 2 +3 8.40 45.7 2 +3 8.50 54.9 2 +3 8.60 65.1 2 +3 8.70 76.1 2 +3 8.80 87.9 2 +3 8.90 100.4 2 +3 9.00 89.4 3 - P \-4E7- b,--TENT,OH ID�=-FTOZ� TR-55 TABULAR HYDROGRAPH METHOD Type II Distribution (24 hr. Duration Storm) Executed: 11-25-1997 11:37:51 Watershed file: --> c:\pondpack\CR-POND .WSD Hydrograph file: --> c:\pondpack\CR-POND .HYD Craven County Airport - Terminal Complex Detention Pond Design »» Input Parameters Used to Compute Hydrograph «« Subarea AREA CN Tc * Tt Precip. I Runoff Ia/p Description (acres) (hrs) (hrs) (in) I (in) input/used ------------------------------------------------------------------------------- Parking Lot 7.00 85.0 0.20 0.00 7.00 1 5.25 .05 .10 Apron 6.70 98.0 0.10 0.00 7.00 1 6.76 .01 .10 Employee Lot 1 1.90 84.0 0.10 0.00 7.00 1 5.14 .05 .10 Employee Lot 2 2.00 73.0 0.10 0.00 7.00 1 3.94 .11 .10 Terminal Area 1.30 98.0 0.10 0.00 7.00 1 6.76 .01 .10 Grassed Area 7.10 73.0 0.30 0.00 7.00 1 3.94 .11 .10 ------------------------------------------------------------------------------- * Travel time from subarea outfall to composite watershed outfall point. Total area = 26.00 acres or 0.04062 sq.mi Peak discharge = 174 cfs Craven County Airport - Terminal Complex Detention Pond Design Time Flow Time Flow (hrs) (cfs) (hrs) (cfs) ----------------- ----------------- 18.6 3 22.4 3 18.7 3 22.5 3 18.8 3 22.6 3 18.9 3 22.7 2 19.0 3 22.8 2 19.1 3 22.9 2 19.2 3 23.0 2 19.3 3 23.1 2 19.4 3 23.2 2 19.5 3 23.3 2 19.6 3 23.4 2 19.7 3 23.5 2 19.8 3 23.6 2 19.9 3 23.7 2 20.0 3 23.8 2 20.1 3 23.9 2 20.2 3 24.0 2 20.3 3 24.1 1 20.4 3 24.2 1 20.5 3 24.3 1 20.6 3 24.4 1 20.7 3 24.5 1 20.8 3 24.6 1 20.9 3 24.7 1 21.0 3 24.8 1 21.1 3 24.9 1 21.2 3 25.0 1 21.3 3 25.1 1 21.4 3 25.2 1 21.5 3 25.3 1 21.6 3 25.4 0 21.7 3 25.5 0 21.8 3 25.6 0 21.9 3 25.7 0 22.0 3 25.8 0 22.1 3 25.9 0 22.2 3 22.3 3 i I p I�� :_ r.iI t J r- RECEIVED POND MAINTENANCE REQUMlMLNTS WASHINGTDN OFFICE Pcojeei Nasnc: I-,a� Iry �t lLt� �ori1 i� �x NOV 2 4 1997 POND MARn7ENANCE REQUIREMENTS .,PAGE 2 ..: tespousiblc part or hereby:acknowledge that I am the financially of this detention pond. 1 will be responsible for the performance of the outlined above, as part of the Stormwater Management Permit received for this project. Date: r a: -��--~��/r\ �_<r'C I •' ! \/ �� �\ \\ \\ -�\'---� Res-\-� _- _ - _ _Hc___= -_- / i I 1 j1 Iv 1� •/01 Al rr it .____ / / — 1 / Ate\ \\ \\ \\ \\\\\\ ���\\ I\\ \e \\ I°\ O \ I Oi /%rn 1\ \'-\ \ \\ \ _,•�� fl VY I - THE LPA GROUP of North Carolina, p.o. Transportation Consultants 4904 Professional Court, Suite 201 Post Office Box 17736 Raleigh, North Carolina 27619 (919) 954-1244 FAX (919) 954-1345 November 11. 1997 Mr. William J. Moore Division of Water Quality NC Dept. of EHNR 943 Washington Square Mall Washington, N.C. 27889 Re: Stormwater Management Plan Terminal Area Site Preparation Craven County Regional Airport New Bern, N.C. Dear Sir: RECEIVED VgASHINGTbN OFFICE Nov 2 4 1997 o.LWL Enclosed is the additional information that you requested. We have "tagged" the section of the calculations that involve the sizing of the wet detention basin. (As reference for this design, we used the "Stormwater Management Guidance Manual' by NCDEHNR). If you should have any questions during the review, please feel free to give me a call. THE AL^PAAGROUP INCORPORATED Scott A. Yar y, .E. Member of THE LPA GROUP INCORPORATED C' ATLANTA, GA o AUSTIN, TX o CHARLESTON, SC o CHICAGO, IL o COLUMBIA, SC o GREENSBORO, NC o KNOXVILLE, TN o MOBILE, AL MYRTLE BEACH, SC 0 PHILADELPHIA, PA 0 RALEIGH, NC 0 TALLAHASSEE, FL 0 TAMPA, FL THE LPA GROUP of North Carolina, p.a. Transportation Consultants 4904 Professional Court, Suite 201 Post Office Box 17736 Raleigh, North Carolina 27619 (919) 954-1244 FAX (919) 954-1345 November 25, 1997 Mr. William J. Moore Division of Water Quality NC Dept. of EHNR 943 Washington Square Mall Washington, N.C. 27889 Re: Stormwater Management Plan Terminal Area Site Preparation Craven County Regional Airport New Bern, N.C. Dear Bill: RECEIVED WASHINGTON OFFICE NOV 2 6 1997 D. L M. We have modified the wet detention basin to provide the required surface area and temporary storage per the table that you sent us earlier in the month. Please note that there is now only one basin, not two. The stormwater runoff being conveyed under the railroad onto the project site will be routed around our project as shown on the enclosed sketch (Double 42" RCP's). This runoff will not be routed through the basin. Please review at your earliest convenience. If you should have any questions during the review, please feel free to give me a call. THE LPA GROUP INCORPORATED Scott A. Yarl Project Engi r Member of THE LPA GROUP INCORPORATED ATLANTA, GA o AUSTIN, TX o CHARLESTON, SC o CHICAGO, IL o COLUMBIA, SC o GREENSBORO, NC o KNOXVILLE, TN o MOBILE, AL MYRTLE BEACH, SC o PHILADELPHIA, PA o RALEIGH, NC o TALLAHASSEE, FL o TAMPA, FL r/-7-92 DIVISION OF WATER QUALITY Z-26-p8 / NORTH CAROLINA STORMWATER MANAGEMENT PERMIT APPLICATIONLJ D I. GENERAL INFORMATION r \ /a1. Project Name: A.i�c4 -J%ZE �A2,6,mc>r4 �`. Prl ject Location: (County, State Road, Address) ['2gyEH lo. i�iE�oNAC dai �'ZC 3. Owner's Name. CeA\ieg L o�,"Y"Rec-%c1,+AL AXV0b Au7HoWyPhone:. 914-0058-8591 4.,' Mailing Address: I5jo l kwa3zi -RD \� /'/ City t4y-;W -&.-Qi.A State HC Zip 0MG0 S. Application Date: AuY 1i I4g2 Fee Submitted: 1-%5.00 6. Nearest Receiving Stream: MEc �5F�R\VeCL Class: -6c--6 -W-A4 7. Project Description: µFtTH Atha::" n&z65 -RQ4�S AND tom—.'�K�rt� A'+�E�a4 Ca*��'�e rev�e•r II. PERMIT INFORMATION p 1. Permit No. (will be completed by DWQ) : f(.4l 7 / 7o(g v 2. Permit Type: X- New Renewal Modification (existing permit no.) 3. Project Type: Low Density X. High Density General Permit Other 4. Other State/Federal Permits/Approvals Required: (Check appropriate blanks) X Sediment/Erosion Control CAMA Major 404 Permit III. PROJECT BUILT UPON AREA Drainage Drainage Basin Basin Classification Allowable Impervious Proposed Impervious Iq z gG Total Project Area Ar- 0 Impervious Area 45.3 X Breakdown of —Impervious Areas Buildings 1.0 AC Roads Jam_ j. Ac• Parking g 2 Ac. other 6AAC KAP2oH) Totals Iq Z AQ WASH TDN OFFICe FEB 2 6 1998 D, E. M, IV. STORMWATER TREATMENT (Describe how runoff will be treated): V., DEED RESTRICTIONS AND PROTECTIVE COVENANTS Deed restrictions and protective covenants are required for all low density projects and all subdivisions prior to the sale of any lot. Please see Attachment A for specific requirements. By your signature below, you certify that the recorded deed restrictions and protective covenants for this project shall include all the items required by the permit, that the covenants will be binding on all parties and persons claiming under them, that they will run with the land, that the covenant cannot be changed or deleted without concurrence from the State, and that they will be recorded prior to the sale of any lot. OWNER'S CERTIFICATION I, �J p E,/,�/ /j`'• 'i�jQ /C E , V /Z certify that the (Please print male Clearly) information included on this permit application form is correct, that the project will be constructed in conformance with the approved plans, that the deed restrictions will be recorded with all required permit conditions, and that to the best of my knowledge, the proposed project complies with the requirements of 15A NCAC 2H.1000. I authorize the below named person or firm to submit stormwater plans on Person or Firm Name: TkF7 L-i�iA C 2pci? c�F H.C. Mailing Address: 4004 ?,O. fox 17736 City �1 F ire" State _HC Zip Z](ol9 Phone: 919- q4 4-1Z44 Please submit application, fee and plans to appropriate Regional office. (see attached map) -2- Rev. 8/96 New Terminal Complex Craven County Regional Airport Stormwater Management Project Narrative ECV WASH II NGTDAOFf ICE FEB 2 6 1998 D. E. M. The Craven County Regional Airport, located in New Bern, N.C., is developing a new terminal complex. The proposed site, which is located to the east of Runway 22, will contain a new terminal building, aircraft apron, access roads, and parking facilities encompassing an area of approximately 42 acres. The proposed site, which was previously used to plant crops, gently slopes towards Scott's Creek, which eventually empties into the Neuse River. Due to the geometry of the proposed development, Scott's Creek will be realigned to convey the flow along the perimeter of the apron and connect to the existing creek alignment downstream. This realigned channel has been designed to convey the stormwater runoff from a storm event greater than the fifty (50) year storm event. Mitigation measures have been included in the design, to replace, and in some cases enhance, the existing ecosystem of the creek. Since this project will increase the impervious surface areas on this site, thereby increasing the volume of runoff, stormwater management measures have been incorporated into the design. The primary stormwater management device used to capture and detain the runoff from the proposed site is a wet detention basin system. The wet detention basin will capture the runoff from an area of 26 acres, of which 14.2 acres will be impervious. (This accounts for approximately 75 percent of the proposed impervious areas). The permanent pool will have a depth of three feet and • have a surface area of 1.20 acres. The forebay area will provide approximately 16 percent of this surface area (8500 sq. feet). Above the permanent pool elevation, a �d y temporary storage volume will be provided to detain the initial runoff. This temporary �- ? storage volume will be released over a period of approximately five days. The temporary storage volume provided for in this design exceeds the minimum required by NCDEHNR guidelines by 19 percent. The outlet structure and the emergency spillway of the wet detention basin have been designed to adequately handle a 25 year storm event. The wet detention basin will be maintenanced based on a schedule of monthly, quarterly, semi-annually, and annually procedures. A gate valve has been provided on the outlet structure so that the basin may be drained if the sediment in the basin needs to be removed or the outlet structure needs to be repaired. The use of this system will not only provide a way of controlling the rate of which stormwater runoff is released from the site, but also provide a method of reducing the pollutants that are released into Scott's Creek. THE LPA GROUP of North Carolina, p.a. Transportation Consultants 4904 Professional Court, Suite 201 Post Office Box 17736 Raleigh, North Carolina 27619 (919) 954-1244 FAX (919) 954-1345 February 25, 1998 Mr. William J. Moore Division of Water Quality INC Dept. of EHNR 943 Washington Square Mall Washington, N.C. 27889 Re: Stormwater Management Plan Terminal Area Site Preparation Craven County Regional Airport New Bern, N.C. Dear Bill: RE WASHIINGTDN OMCE FEB 2 6 1998 D. E. M. Enclosed are the revisions and/or clarifications that we discussed on the telephone on February 24, 1998. We have also included two partial sets of plans and calculations for your use. The revisions and/or clarifications are as follows: • The discrepancy in regards to the total drainage areas and impervious areas can best be explained as follows: From the original application submitted to your office on August 8, 1997, the total project area and proposed impervious areas were 42 ac. and 19.2 ac., respectively. These numbers are correct for the overall project site and the ultimate build -out condition. In the design of the wet pond, the existing drainage area and the proposed impervious areas draining "to" the proposed wet pond (26 ac. and 14.2 ac., respectively), were used. We have checked these areas again and they are correct. • We have included a copy of the original application for your records. The areas shown reflect the total project area and the ultimate build -out condition. Member of THE EPA GROUP INCORPORATED ATLANTA, GA • AUSTIN, TX • CHARLESTON, SC • CHICAGO, IL • COLUMBIA, SC • GREENSBORO, NC • KNOXVILLE, TN • MOBILE, AL MYRTLE BEACH, SC 0 PHILADELPHIA, PA • RALEIGH, NC 9 TALLAHASSE, FL 0 TAMPA, FL Page 2 • The narrative has been revised and is included in this submittal. • A forebay has been added to the wet pond, and rip rap protection has been added to the outlets of the two culverts entering the pond. • An inverted drawdown pipe has been added to the outlet structure. (See DR-3). If you should have any questions during the review, please feel free to give me a call. THE `gy. GROUP INCORPORATED Scott A. YarE. THE LPA GROUP of North Carolina, p.a. Transportation Consultants 4904 Professional Court, Suite 201 Post Office Box 17736 Raleigh, North Carolina 27619 (919) 954-1244 FAX (919) 954-1345 May 7, 1998 Mr. William J. Moore Division of Water Quality NC Dept. of EHNR 943 Washington Square Mall Washington, N.C. 27889 RECEIVED Sw V 7o g (� WASHiNGTON OFFICE 14D iss 1 1998 D. L M. Re: Stormwater Management Plan Terminal Area Paving and Lighting Craven County Regional Airport New Bern, N.C. Dear Bill: Enclosed is a copy of drawing no. GD-1, of the above referenced project, per your request. We have shown in red the existing drainage ditch that runs along the airport property line and intersects Scotts Creek. The proposed double 24" RCP's will basically convey the stormwater runoff under the proposed roadway. The drainage area and patterns will essentially remain unchanged from that of the existing conditions. Please review and if you should have any questions or comments, please contact this office. Sincerely, TH�GROUPINCORPORATED Scott A. Y I P Project En ' eer Member of THE LPA GROUP INCORPORATED ATLANTA, GA • AUSTIN, TX • CHARLESTON, SC • CHICAGO, IL • COLUMBIA, SC • GREENSBORO, NC • KNOXVILLE, TN • MOBILE, AL MYRTLE BEACH, SC 0 PHILADELPHIA, PA 0 RALEIGH, NC 0 TALLAHASSE, FL 0 TAMPA, FL THE LPA GROUP of North Carolina, p.a. ) r r; _",':.-`i Transportation Consultants Recv4 4904 Professional Court, Suite 201 0SVI,i`.�.":, ;:.: Post Office Box 17736 Raleigh, North Carolina 27619 (919) 954-1244 FAX (919) 954-1345 March 24, 1998 Mr. Patrick McClain, P.E Regional Engineer - N.C. Department of Environment, and Natural Resources Washington Regional Office 943 Washington Square Mall Washington, North Carolina 27889 Re: Craven County Regional Airport Terminal Area Development Dear Pat: Please find enclosed two copies of the grading and drainage plans for the extension of the Terminal Entrance Road at the Craven County Regional Airport for your review and approval. This section of road was not included in the previous erosion control plans. We have also enclosed a check in the amount of $20.00, to cover the fee for the plan review. If you have any questions, please feel free to contact me. Sincerely, The LPA GROUP of North Carolina, p.a. ieffrtlyM.Kirby, P.E. Project Engineer Enclosures cc: Mr. John Price �o 5") 4 Ss;1VAPyPf P4, Member of THE LPA GROUP INCORPORATED ATLANTA, GA 0 AUSTIN, MYRTLE BEACH, ON.S PHILADELPHIAA,, PA • RALEIGH, NC • TALLAHADORQ: TAMPAOLVILLE, TN MOBILE, AL r`F`R Michael F. Easley, Governor Qe'i William G. Ross Jr., Secretary r� 4 1\\ r North Carolina Department of Environment and Natural Resources ��•/� < Coleen H. Salina. Director Division of Water Quality June 12, 2007 Craven County Regional Airport Authority Attn: James Creech, Chair Post Office Box 3258 New Bern, NC 28564-2358 Subject:: Stormwater Permit No. SW7970812 Craven Airport— 97 Terminal Improvements Craven County Dear Mr. Creech: The Division of Water Quality issued a Coastal Stormwater Management Permit, Number SW7970812 for Craven Airport — 97 Terminal Improvements.on March 19, 1998. This permit expires on March 19; 2008. Section .1003(h) of 15 A NCAC 2H .1000 (the stormwaterrules) requires that applications for permit renewals shall be submitted 180 days prior to the expiration of a permit and must be accompanied by a processing fee, which is currently set at $420.00. If this is still an active project please complete and submit the enclosed renewal application in a timely manner. If this project has not been constructed and a permit is no longer needed, please submit a request to have the permit rescinded. If you have sold the project, or are no longer the permittee, please provide the name, mailing address and phone number of the person or entity that is now responsible for this permit. Enclosed is a form for change of ownership, which should be completed and submitted if the property has changed hands. Your permit requires that upon completion of construction and prior to operation of the permitted treatment units a certification of completion be submitted to the Division from an appropriate designer for the system installed. This is to certify that the permitted facility has been installed in accordance with the permit, the approved plans, specifications and supporting documentation. Please include a copy of the certification with your permit renewal request and processing fee. Enclosed is a copy of a sample certification. Also enclosed is a new Operation and Maintenance agreement that should be completed and submitted along with your renewal application. You should be aware that failure to provide the Designer's Certification and the operation of a stormwater treatment facility without a valid permit, are violations of NC General Statute 143-215.1 and may result in appropriate enforcement action including the assessment of civil penalties of up to $10,000 per day. If you have any questions, please feel free to contact us at 252-946-6481. incere�y, L Al Hodge, eglonal Supervisor Surface Water Protection Section Washington Regional Office Enclosures cc: The LPA Group of NC, PA, 4904 Professional Court, Suite 201, PO Box 17736, Raleigh, NC 27619 VV�ashington Regional Office North Carolina Division of Water Quality Internet: www.ncwvatereualitv.ore One 943 Washington Square Mall Phone (252) 946-6481 N���fffo�ft thCarolina Washington, NC 27889 Fax (252) 946-9215 /' odulrall , An Equal Opportunity/Affirmative Action Employer- 50%Recycled110% Post Consumer Paper f� rLLVK`hLts�/