Land Development Code - Article VII - Stormwater Management

10 LAND DEVELOPMENT CODE ARTICLE VII STORMWATER MANAGEMENT __________ Cross references Utilities , ch 24 __________ Sec 14 - 381 Purpose The purpose of this article is to establish minimum criteria to control and minimize quantitative and qualitative impacts of stormwater runoff from development within the county , a nutrient management program for new development in accordance with 15A NCAC 2B 0235 Neuse River Basin - Nutrient Sensitive Waters Management Strategy Basinwide Stormwater Requirements and to establish regulations to provide additional protection within the environmentally sensitive area district ES Further , prudent site planning should include special consideration for the purposes of preserving natural drainageways , maximizing infiltration , and slowing stormwater runoff from individual sites en route to streams and rivers by use of effective runoff management , structural and nonstructural best management practices , drainage structures , and stormwater facilities Ord of 7 - 10 - 2000 , § 91 ; Ord of 1 - 2 - 2001 , § 91 Sec 14 - 382 Applicability The provisions of this article shall apply to all areas within the planning jurisdictional limits of the county The provisions of the environmentally sensitive area district shall apply to those areas defined and established on the map entitled Environmentally Sensitive Areas of Johnston County , North Carolina Ord of 7 - 10 - 2000 , § 92 ; Ord of 1 - 2 - 2001 , § 92 Sec 14 - 383 Exceptions to applicability The provisions of this article shall not apply to 1 Developers property owners that can demonstrate that they have vested rights as of the adoption date of the revised stormwater ordinance from which this article is derived shall be exempt from the revised stormwater ordinance 2 Exemption from storm attenuation Developments that meet one of the following requirements shall be exempt from storm attenuation a The increase in peak flow between pre - and post - development conditions does not exceed ten percent ; or b The proposed development meets all of the following criteria overall impervious surface is less than 15 percent outside the ES and 12 percent inside the ES , and the pervious portions of the site are utilized to the extent practical to convey and control stormwater runoff Nutrient management and or reduction shall still be required Ord of 7 - 10 - 2000 , § 921 ; Ord of 1 - 2 - 2001 , § 921 56 Revised 1 08PageSec 14 - 384 Definitions The following words , terms and phrases , when used in this article , shall have the meanings ascribed to them in this section , except where the context clearly indicates a different meaning Applicant means an owner or developer of a site who executes the stormwater permit application pursuant to this article and is considered the applicant Best management practices BMPs means a wide range of practices that have been demonstrated to effectively manage the quality and or quantity of stormwater runoff and which are compatible with the planned land use BMPs can be structural detention ponds , wetlands , etc or nonstructural reduced road pavement width , cluster development , etc Channel bank means the location of the upper edge of the active channel above which the water spreads into the overbanks on either side of the channel or the elevation of the two - year frequency storm Where the channel bank is not well defined , the channel bank shall be considered the edge of the waterline Design storm means the specific frequency and , if necessary , duration of the rainfall event to be used in design to meet the criteria established in the stormwater design manual Development means any of the following actions taken by a public or private individual or entity 1 The division of a lot , tract or parcel of land into two or more lots , plots , sites , tracts , parcels or other divisions by plat or deed ; or 2 Any land change , including , without limitation , clearing , tree removal , grubbing , stripping , dredging , grading , excavating , transporting and filling of land Drainage structures include swales , channels , storm sewers , curb inlets , yard inlets , culverts and other structures designed to convey stormwater Existing development means an individual nonresidential site with site plan approval by the planning department or a nonresidential or residential subdivision with preliminary subdivision approval from the planning board Illegal discharge means any unlawful disposal , placement , emptying , dumping , spillage , leakage , pumping , pouring , or other discharge of any substance other than stormwater into a stormwater conveyance system , the waters of the state or upon the land such that the substance is likely to reach a stormwater conveyance system or waters of the state and constitutes an illegal discharge Impervious surface means a surface composed of any material that impedes or prevents natural infiltration of water into the soil Gravel areas shall be considered impervious Land disturbance means removal of topsoil , grubbing , stump removal and or grading Natural drainageway means an incised channel with a defined channel bed and banks that are part of the natural topography Construction channels such as drainage ditches shall not be considered a natural drainageway unless the constructed channel was a natural drainageway that has been relocated , widened , or otherwise improved New development means as follows 1 Any activity that disturbs more than one acre of land or creates more than 17,000 square feet of impervious surfaces for a single - family or duplex residential development , recreational facility , or multifamily , institutional , commercial or industrial development ; and 57 Revised 1 08Page 2 New development shall not include mining , agricultural or forestry activities Riparian buffer means an area of trees , shrubs , or other forest vegetation , that is adjacent to surface waters For purposes of this article , surface water shall be present if the feature is approximately shown on either the most recent version of the county soil survey report prepared by the NRCS or the most recent version of the 1 24,000 scale 75 min quadrangle topographic maps prepared by the United States Geological Survey Riparian buffers adjacent to surface waters that do not appear on either of the maps shall not be subject to this article , except as noted in section 14 - 103 Stormwater means flow resulting from and occurring after any form of precipitation Stormwater administrator means the person designated by the county manager to have authority to review and approve stormwater permits and stormwater management plans The stormwater administrator shall also be responsible for inspecting development and enforcing the provisions of this article Stormwater conveyance system or structure means any feature , natural or manmade , that collects and transports stormwater , including , but not limited to , roadways with collection systems , catch basins , manmade and natural channels , streams , pipes and culverts , and any other structure or system designed to transport runoff Stormwater design manual means the manual of design , performance , and review criteria adopted by the board of commissioners for the administration of the stormwater program Vegetative buffer means an area that has a dense ground cover of herbaceous or woody species , which provides for diffusion and infiltration of runoff and filtering of pollutants Vested rights for stormwater shall be based upon the following criteria 1 Having an outstanding valid building permit in compliance with GS 153A - 3441 or GS 160A - 3851 ; or 2 Having an approved site specific or phased development plan in compliance with GS 153A - 3441 or GS 160A - 3851 Projects that require a state permit , such as landfills , NPDES wastewater discharges , land application or residuals and road construction activities , shall be considered to have vested rights if a state permit was issued prior to the effective date of the adoption of the revised stormwater ordinance from which this article is derived Water dependent structures means those structures that require the access or proximity to , or sitting within surface waters to fulfill its basic purpose , such as boat ramps , boathouses , docks , and bulkheads Ancillary facilities such as restaurants , outlets for boat supplies , parking lots , and commercial boat storage areas are not considered water - dependent structures Ord of 7 - 10 - 2000 , § 93 ; Ord of 1 - 2 - 2001 , § 93 Cross references Definitions generally , § 1 - 2 Sec 14 - 385 Interpretation In interpreting and applying this article , the requirements are intended to be minimum requirements , which are imposed and are to be conformed to , and are in addition to , and not in lieu of , all other legal requirements This section shall not be deemed to interfere with or annul or otherwise affect in any manner whatsoever any ordinance , rule , regulation , permit , or easement , covenant , or other agreement between parties ; provided , however , where this article imposes greater restrictions and controls with respect to 58 Revised 1 08Pagestormwater management , the provisions of this article shall prevail Ord of 1 - 2 - 2001 , § 94 Sec 14 - 386 Enforcement a Violations Whenever , by the provisions of this article , the performance of any act is required , or the performance of any act is prohibited , or whenever any regulation or limitation is imposed on the use of any land , or on the erection , alteration , or the use or change of use of a structure , a failure to comply with such provisions shall constitute a violation of this article The owner , tenant , or occupant of any land or structure , or part thereof , and any architect , engineer , builder , contractor , agent , or other person who participates in , assists , directs , creates , or maintains any situation that is contrary to the requirements of this article may be held responsible for the violation and be subject to the penalties and remedies provided in this section Failure to follow an approved stormwater management plan or permit shall constitute a violation of this article and shall be subject to the penalties and remedies provided in this article b Procedures upon discovery of violations Procedures upon discovery of violations of this article shall be as follows 1 Upon determination that any provision of this article is being violated , the stormwater administrator shall deliver a written notice by personal service or by registered or certified mail , return receipt requested , to the person responsible for such violation , indicating the nature of the violation , ordering the action necessary to correct it and outlining the timeframe for gaining compliance Additional written notices may be sent at the stormwater administrators discretion 2 The final written notice , which may also be the initial notice , shall state the enforcement action the county intends to take if the violation is not corrected , and shall advise that the stormwater administrators order may be appealed to the board of adjustment as provided in article XI of this chapter In cases when delay would seriously threaten the effective enforcement of this article , or pose a danger to the public health , safety , or general welfare , the stormwater administrator may seek enforcement without prior written notice by invoking any of the penalties or remedies contained in this section c Penalties and remedies Penalties and remedies for a violation of this article shall be as follows 1 Any violation of any provision of any section of this article shall constitute a misdemeanor and shall subject the violator to a penalty of 50000 and or imprisonment for not more than 30 days 2 Development that begins land disturbing activities prior to obtaining a stormwater management permit shall also be subject to a one - time 1,00000 penalty 3 Illegal discharge Any designer , engineer , consultant , contractor or person that allows , acts in concert , participates , directs or assists directly or indirectly in an illegal discharge shall be subject to civil penalties as follows a For first time offenders if the quantity of the discharge is equal to or less than five gallons and consists of domestic or household products , such person shall be assessed a civil penalty not to exceed 10000 per violation or per day for any continuing violation If the quantity of the discharge is greater than five gallons or contains nondomestic substances or if the person cannot provide clear and convincing evidence of the volume 59 Revised 1 08PagePage pageNumber5and nature of the substance discharged , such person shall be assessed a civil penalty not to exceed 1,00000 per violation or per day for any continuing violation b For repeat offenders , the amount of the penalty shall be double the amount assessed for the previous penalty , not to exceed 10,00000 per violation or per day for any continuing violation c The county manager or his designee shall take the following into consideration when determining the civil penalty amount 1 The degree and extent of harm to the environment , public health , and property ; 2 The cost of remedying the damage ; 3 The willfulness of the violation ; 4 The duration of the violation ; 5 The violators prior record in complying or failing to comply with this article ; and 6 The amount of money saved by the violator by noncompliance If the offender fails to pay the penalty within ten days of receiving final written notice of a violation , the county in a civil action may recover the penalty A civil penalty may not be appealed to the board of adjustment if the offender received a final written notice of violation and did not appeal to the board of adjustment within 30 days Each day that any violation continues after receipt of the final written notice of such violation shall constitute a separate violation and a separate offense for purposes of the penalties and remedies specified in this section In addition to the penalties and remedies of this section , the county may institute any appropriate action or proceedings to prevent , restrain , correct , or abate a violation of this article Ord of 1 - 2 - 2001 , § 913 Sec 14 - 387 Drainage system Stormwater shall be conveyed from a development in an adequately designed drainage system of natural drainageways , grass swales , storm sewers , culverts , inlets , and channels Drainage systems shall be designed , constructed , and maintained to encourage natural infiltration , control velocity , control flooding , and extend the time of concentration of stormwater runoff The post - development runoff rate for the one - year storm event shall be attenuated to the predevelopment runoff rate for the one - year storm The nitrogen loading contributed by new development shall be restricted to 36 pounds of nitrogen per acre per year Methodologies for determining nitrogen loading are outlined in the stormwater design manual A developer has the option of offsetting the nitrogen loading from a development by paying into the state wetlands restoration program Procedures for offset payments are outlined in the stormwater design manual When using the offset payment , the total nitrogen loading from a development shall not exceed six pounds per acre per year for residential development and ten pounds per acre per year for nonresidential development Ord of 7 - 10 - 2000 , § 95 ; Ord of 1 - 2 - 2001 , § 97 Sec 14 - 388 Stormwater permit a Except where provided elsewhere in this chapter , land disturbing activities shall not commence without obtaining a stormwater permit pursuant to the provisions of this article and the stormwater design manual The stormwater permit application shall be made by , or on behalf of , the owner or developer of the site for which the permit is 60 Revised 1 08PagePage pageNumber6sought The application shall be filed with the county on a form supplied by the county and shall be accompanied with the information identified in the stormwater design manual A stormwater permit shall not be issued until the following conditions are met 1 Approval of the stormwater management plan by the stormwater administrator 2 Submission and approval of any required easements and impervious area statements on a map to be recorded 3 Submission and approval of any required inspection and maintenance agreement and or escrow account or other legal instrument established to ensure long - term maintenance of BMPs 4 Payment of all fees b If the development requires approval of an erosion and sediment control plan , the stormwater permit will be conditional upon the owner receiving such erosion and sediment control approval The stormwater permit will be valid for one year from the date of issuance or until significant changes in the development are made that change the intent of the permit The stormwater administrator shall determine significant changes If significant changes are made , the original stormwater permit shall not be valid , and a new permit shall be required Ord of 7 - 10 - 2000 , § 94 ; Ord of 1 - 2 - 2001 , § 95 Sec 14 - 389 Fees A list of fees associated with this article is available at the office of the clerk to the board of commissioners in the county courthouse Ord of 1 - 2 - 2001 , § 96 Sec 14 - 390 Stormwater management plans Stormwater management plans shall 1 Include drawings , maps , supporting calculations , specifications , and summaries as outlined in the stormwater design manual 2 Demonstrate through accepted engineering practices described in the stormwater design manual the impacts of the proposed development Impacts of the proposed development shall include a Effects on existing upstream and or downstream drainage systems and property ; b Ability of the natural drainageway to handle additional stormwater runoff ; and c Site - specific criteria supporting the analysis of any impacts noted in subsections 2 a and 2 b of this section 3 Demonstrate through accepted engineering practices described in the stormwater design manual that stormwater runoff is adequately conveyed through the development in a drainage system designed to meet the criteria described in the stormwater design manual 4 Demonstrate through accepted engineering practices described in the stormwater design manual that stormwater facilities required to control the impacts of the development are designed to meet the criteria described in the stormwater design manual 5 Demonstrate that the nitrogen loading from the new development does not exceed the limits set forth in section 14 - 387 Ord of 7 - 10 - 2000 , § 951 ; Ord of 1 - 2 - 2001 , § 971 61 Revised 1 08PagePage pageNumber7Sec 14 - 391 Stormwater BMP inspection , maintenance and easement requirements a Maintenance agreement A written inspection and maintenance agreement in a form acceptable to the county attorney and executed by the applicant and the owner of the BMP , if different than the applicant , shall be provided prior to receiving a stormwater permit The agreement shall 1 Bind the parties thereto and all subsequent owners , successors , and assigns to maintenance and inspection of the system or structure 2 State that if the county directs the correction , repair , replacement , or maintenance of the system or structure in writing and the actions are not satisfactorily performed within a reasonable time but not greater than 120 days , the county or its contractors may , after reasonable notice , enter the land and perform all the necessary work and may assess the owner of the facility with the cost of the work performed or the county can seize all or part of the escrow or other fund set aside by the applicant for perpetual maintenance The owner served by the facility shall be jointly responsible to the county for the maintenance of the facility and liable for any costs incurred by the county pursuant to the agreement All properties are jointly subject to the imposition of the liens for such costs 3 The inspection and maintenance agreement shall be recorded in the register of deeds at the expense of the applicant b Easements Easements for stormwater BMPs shall include the area of the BMP , area of ponded water , and enough area for access and maintenance The easement shall be recorded in the register of deeds at the expense of the applicant and shall be depicted on the final plat or recorded map Ord of 7 - 10 - 2000 , § 96 ; Ord of 1 - 2 - 2001 , § 98 Sec 14 - 392 Discharges and connections a Illegal discharge No person shall cause or allow the discharge , disposal , pouring or pumping directly or indirectly to any stormwater conveyance structure , stormwater conveyance system , stream , lake , pond , wetland or other body of water , or upon the land in proximity to the same , any fluid , solid or other substance other than stormwater Prohibited substances include , but are not limited to oil , antifreeze , chemicals , animal waste , paints , garbage and litter Examples of illegal discharges are 1 Dumping of oil , antifreeze , paint or cleaning fluids 2 Untreated commercial carwash washwater 3 Industrial discharges 4 Contaminated foundation drains 5 Cooling waters , unless no chemicals are added and have a valid NPDES permit 6 Washwater from commercial and industrial activities 7 Chlorinated backwash and draining associated with swimming pools 8 Domestic wastewater 9 Septic system effluent 10 Washing machine discharges b Allowable discharges Examples of allowed discharges under this article are 1 Water line flushing 2 Irrigation 3 Uncontaminated groundwater pumping 62 Revised 1 08PagePage pageNumber8 4 Street wash water 5 Dechlorinated backwash and drainage associated with swimming pools 6 NPDES permitted discharges c Illegal connections Connections to a stormwater conveyance system or structure that allow the discharge of nonstormwater are unlawful Prohibited connections include , but are not limited to 1 Floor drains 2 Wastewater from washing machines or sanitary sewers 3 Wash water from commercial vehicle washing or steam cleaning 4 Wastewater from septic systems d Determination of connection Upon determining that a connection to a stormwater conveyance system 1 May result in the discharge of hazardous materials , may pose a threat to health and safety , or is likely to result in immediate injury or harm to human or animal life , natural resources , to real or personal property , or habitat ; or 2 Was made in violation of any applicable regulation or ordinance The stormwater administrator shall outline in a notice of violation , sent by certified mail , the time in which the connection shall be removed Failure to comply with the terms and deadlines set in the notice of violation will constitute a violation of this article Ord of 1 - 2 - 2001 , § 99 Sec 14 - 393 Riparian buffers Fifty - foot wide riparian buffers shall be maintained along both sides of a stream , river or other waterbody as required by the Neuse River Basin Nutrient Sensitive Waters Management Strategy Protection and Maintenance of Riparian Buffers , Section 3 a - b Riparian buffers shall be noted on the maps submitted for stormwater management plan approval and shall be noted on the final recorded map Determinations of exemptions as noted in 15A NCAC 2B 0233 Neuse River Basin Nutrient Sensitive Waters Management Strategy Protection and Maintenance of Riparian Buffers , Section 3 a - b shall be made by the NCDENR Division of Water Quality Ord of 7 - 10 - 2000 , § § 97 , 98 ; Ord of 1 - 2 - 2001 , § 910 Sec 14 - 394 Right to enter Any county personnel , or contractors for the county , shall be permitted to enter upon public or private property for the purposes of inspection , sampling , monitoring , testing or otherwise verifying compliance Should the county personnel , or contractor for the county , be denied reasonable access to any property , the stormwater administrator shall obtain an administrative search warrant No person shall obstruct , hamper or interfere with any such representative while carrying out his official duties Ord of 1 - 2 - 2001 , § 911 Sec 14 - 395 Variances The board of adjustment shall consider all variance requests as set out in article XI of this chapter Ord of 7 - 10 - 2000 , § 910 ; Ord of 1 - 2 - 2001 , § 912 Secs 14 - 396 - - 14 - 420 Reserved 63 Revised 1 08Page