IT’S TIME TO GET YOUR IT’S TIME TO GET YOUR MIND IN THE GUTTER! MIND IN THE GUTTER!

Overview of Proposed Coastal Overview of Proposed Coastal Stormwater RulesStormwater Rules

February 14, 2008February 14, 2008

Rules Affect ALL Land in Rules Affect ALL Land in Twenty Coastal Counties With Twenty Coastal Counties With

Disturbance Greater Than Disturbance Greater Than 10,000 Sq. Ft.10,000 Sq. Ft.

Beaufort, Bertie, Camden, Carteret, Beaufort, Bertie, Camden, Carteret, Chowan, Craven, Currituck, Dare, Gates, Chowan, Craven, Currituck, Dare, Gates, Hertford, Hyde, Pamlico, Pasquotank, Hertford, Hyde, Pamlico, Pasquotank, Pender, Perquimans, Tyrrell, Washington Pender, Perquimans, Tyrrell, Washington

AND Phase II Counties - Brunswick, New AND Phase II Counties - Brunswick, New Hanover and Onslow.Hanover and Onslow.

Understanding the Rules:Understanding the Rules:Definition of TermsDefinition of Terms

• Land Disturbing ActivityLand Disturbing Activity

• Built-Upon AreaBuilt-Upon Area

• Lot CoverageLot Coverage

• Vegetative BufferVegetative Buffer

• SA WatersSA Waters

Land Disturbing ActivityLand Disturbing Activity

DWQ Definition:DWQ Definition:

Any use of the land that results in a Any use of the land that results in a change in the natural cover or change in the natural cover or topography that may cause or topography that may cause or contribute to sedimentation.contribute to sedimentation.

Built-Upon Area (BUA)Built-Upon Area (BUA)

That portion of a project that is covered by That portion of a project that is covered by impervious or partially impervious surface impervious or partially impervious surface including, but not limited to, buildings; pavement including, but not limited to, buildings; pavement and gravel areas such as roads, parking lots, and and gravel areas such as roads, parking lots, and paths; and recreation facilities such as tennis paths; and recreation facilities such as tennis courts. courts.

Does not include a wooden slatted deck, the water Does not include a wooden slatted deck, the water area of a swimming pool, or pervious or partially area of a swimming pool, or pervious or partially pervious paving material to the extent that the pervious paving material to the extent that the paving material absorbs water or allows water to paving material absorbs water or allows water to infiltrate through the paving material. Septic infiltrate through the paving material. Septic systems/drain fields are not impervious surfaces.systems/drain fields are not impervious surfaces.

BUA – How is it measured?BUA – How is it measured?

• Built-upon area is a measure of the hard surfaces Built-upon area is a measure of the hard surfaces or impervious cover for a site. For each piece of or impervious cover for a site. For each piece of land, divide the amount (area) of impervious land, divide the amount (area) of impervious surface (i.e.:  structures, roads, parking lots) surface (i.e.:  structures, roads, parking lots) located on-site by the total land area under located on-site by the total land area under consideration. Multiply the resulting fraction by consideration. Multiply the resulting fraction by 100 to get the percent built-upon area. 100 to get the percent built-upon area.

• If disturbing more than one acre of land for If disturbing more than one acre of land for residential development, or 10,000 sq. ft. for non-residential development, or 10,000 sq. ft. for non-residential development, wetlands cannot be residential development, wetlands cannot be included in total land area under consideration.included in total land area under consideration.

Lot CoverageLot Coverage

• Defined by each municipality and Defined by each municipality and County.County.

• Do not confuse with Built-Upon Area.Do not confuse with Built-Upon Area.

• Prior built-upon area low density Prior built-upon area low density thresholds (25%/30%) may have thresholds (25%/30%) may have been more flexible than local lot been more flexible than local lot coverage allowance. coverage allowance.

Vegetated BufferVegetated Buffer

• "Vegetative Buffer" means an area of natural or "Vegetative Buffer" means an area of natural or established vegetation directly adjacent to established vegetation directly adjacent to surface waters through which stormwater runoff surface waters through which stormwater runoff flows in a diffuse manner to protect surface flows in a diffuse manner to protect surface waters from degradation due to development waters from degradation due to development activities. activities.

• The width of the buffer is measured horizontally The width of the buffer is measured horizontally from the normal pool elevation of impounded from the normal pool elevation of impounded structures, from the bank of each side of streams structures, from the bank of each side of streams or rivers, and from the mean high water line of or rivers, and from the mean high water line of tidal waters, perpendicular to the shoreline."tidal waters, perpendicular to the shoreline."

Will I Need A Stormwater Will I Need A Stormwater Permit?Permit?

Section ASection A

• ResidentialResidential

Permitting threshold is Permitting threshold is one acreone acre of land of land disturbance.disturbance.

If you are clearing, If you are clearing, grading, etc. one acre grading, etc. one acre or more –you will need or more –you will need to apply for a state to apply for a state stormwater permit.stormwater permit.

• Non-ResidentialNon-Residential

Permitting threshold is Permitting threshold is 10,000 sq. ft. of land 10,000 sq. ft. of land disturbancedisturbance

Includes projects that Includes projects that disturb less than disturb less than 10,000 sq. ft. but are 10,000 sq. ft. but are part of a larger plan part of a larger plan for development or for development or sale. sale.

SA WatersSA Waters

• Commercial shellfishing waters.Commercial shellfishing waters.

• Domestic Wastewater Discharges are Domestic Wastewater Discharges are not allowed.not allowed.

• Provisions for stormwater controls. Provisions for stormwater controls.

• Class SA Waters also carry a Class SA Waters also carry a supplemental designation of HQW supplemental designation of HQW (High Quality Water) or ORW (High Quality Water) or ORW (Outstanding Resource Water).(Outstanding Resource Water).

Dare County SA Waters MapDare County SA Waters Map

http://h2o.enr.state.nc.us/admin/maps/couhttp://h2o.enr.state.nc.us/admin/maps/counties/documents/dare.pdfnties/documents/dare.pdf

Boundaries on map includeBoundaries on map include land “within ½ mile of SA waters” land “within ½ mile of SA waters”

No SA WatersNo SA Waters

• Part of Kill Devil Hills, Kitty Hawk, Part of Kill Devil Hills, Kitty Hawk, Southern Shores, Duck, Currituck Southern Shores, Duck, Currituck Outer BanksOuter Banks

• Majority of downtown ManteoMajority of downtown Manteo

• East LakeEast Lake

• Bertie, Camden, Chowan, Currituck, Bertie, Camden, Chowan, Currituck, Gates, Hertford, Perquimans, Tyrell, Gates, Hertford, Perquimans, Tyrell, Washington Washington

Residential ExclusionResidential Exclusion

If your lot is part of a larger subdivision If your lot is part of a larger subdivision that was issued a stormwater permit, that was issued a stormwater permit, you do not need to do anything for you do not need to do anything for stormwater runoff – you’re already stormwater runoff – you’re already

covered under that permit!covered under that permit!

I Need a Permit – Next Step:I Need a Permit – Next Step:Determine Built-Upon AreaDetermine Built-Upon Area

• As noted previously, wetlands cannot be As noted previously, wetlands cannot be included in the overall project area to included in the overall project area to calculate impervious surface density calculate impervious surface density (BUA).(BUA). – This does not mean that wetlands cannot be This does not mean that wetlands cannot be

impacted – the BUA percentage is only used to impacted – the BUA percentage is only used to determine whether your project needs to determine whether your project needs to comply with LOW DENSITY or HIGH DENSITY comply with LOW DENSITY or HIGH DENSITY stormwater requirements.stormwater requirements.

I Need a Permit:I Need a Permit:New Buffer RequirementNew Buffer Requirement

• A 50-foot vegetated buffer is required A 50-foot vegetated buffer is required whether low or high density; a lawn would whether low or high density; a lawn would qualify as “vegetated” – Buffer is similar to qualify as “vegetated” – Buffer is similar to “setback”. Buffer rules are different in the “setback”. Buffer rules are different in the Tar-Pam and Neuse River Basins. Tar-Pam and Neuse River Basins. (Increased from 30-foot)(Increased from 30-foot)

Buffer (con’t)Buffer (con’t)

• 30-foot buffer for redevelopment30-foot buffer for redevelopment– provided there is no net increase in impervious provided there is no net increase in impervious

surfaces and the redevelopment incorporates surfaces and the redevelopment incorporates equal or better stormwater controls that the equal or better stormwater controls that the previous development. previous development.

– Provision allows for the rebuilding of homes, Provision allows for the rebuilding of homes, businesses and other structures in the event of businesses and other structures in the event of natural disasters without mandating strict natural disasters without mandating strict compliance with the new provisions in the rules.compliance with the new provisions in the rules.

I Need a Permit – Am I Within I Need a Permit – Am I Within One-Half Mile and Draining to One-Half Mile and Draining to SA Waters SA Waters • SA Waters Map - DWQSA Waters Map - DWQ

• Land Quality Map Land Quality Map

• Streams or Tributaries on Property Streams or Tributaries on Property – If rated as a stream or tributary but not If rated as a stream or tributary but not

appearing on a map – requirements will appearing on a map – requirements will still need to be met and the “within ½ still need to be met and the “within ½ mile” rule would include areas adjacent to mile” rule would include areas adjacent to the stream or tributary. (Make sure a the stream or tributary. (Make sure a ditch is a ditch!)ditch is a ditch!)

Yes – I’m Within One-Half Mile Yes – I’m Within One-Half Mile ……What is the BUA?What is the BUA?• Low Density – 12% or Less BUALow Density – 12% or Less BUA

– Runoff transported by vegetated Runoff transported by vegetated conveyancesconveyances

OROR• High Density – Over 12% BUAHigh Density – Over 12% BUA

– Control systems must be infiltrations Control systems must be infiltrations systems, wet detention ponds, bioretention systems, wet detention ponds, bioretention systems, constructed wetlands, sand filters systems, constructed wetlands, sand filters or ALTERNATIVE STORMWATER or ALTERNATIVE STORMWATER MANAGEMENT SYSTEM.MANAGEMENT SYSTEM.

High Density (con’t)High Density (con’t)

• Systems will need to control and treat runoff from Systems will need to control and treat runoff from all impervious surfaces by one and one-half all impervious surfaces by one and one-half inches or rainfall or the DIFFERENCE in the runoff inches or rainfall or the DIFFERENCE in the runoff from pre and post-development conditions for the from pre and post-development conditions for the one-year 24-hour storm – whichever is greater. one-year 24-hour storm – whichever is greater. (In Dare County, the one-year 24-hour storm (In Dare County, the one-year 24-hour storm condition is approx. 3 ½ inches of rain)condition is approx. 3 ½ inches of rain)

• If INFILTRATION meets the requirements under If INFILTRATION meets the requirements under the rules then it will be acceptable as an the rules then it will be acceptable as an alternative system.alternative system.

All Permits - Low All Permits - Low andand High High Density RequirementsDensity Requirements

• Prohibit new points of stormwater dischargeProhibit new points of stormwater discharge

• No expansion of existing conveyance No expansion of existing conveyance systems draining to SA waterssystems draining to SA waters

• No increase in net amount or rate of No increase in net amount or rate of discharge through existing outfallsdischarge through existing outfalls

• Infiltration of the one-year 24-hour storm? Infiltration of the one-year 24-hour storm? Intent is “No NEW runoff from the 1-yr 24-Intent is “No NEW runoff from the 1-yr 24-hour storm. (Confusing and needs hour storm. (Confusing and needs clarification)clarification)

I Need a Permit but I’m Outside I Need a Permit but I’m Outside of One-Half Mile SA …., ETC.of One-Half Mile SA …., ETC.• Low Density – 24% or Less BUALow Density – 24% or Less BUA

– Runoff transported by Vegetated ConveyanceRunoff transported by Vegetated Conveyance

OROR

• High Density – Over 24% BUAHigh Density – Over 24% BUA– Control systems must be infiltrations systems, Control systems must be infiltrations systems,

wet detention ponds, bioretention systems, wet detention ponds, bioretention systems, constructed wetlands, sand filters or constructed wetlands, sand filters or ALTERNATIVE STORMWATER MANAGEMENT ALTERNATIVE STORMWATER MANAGEMENT SYSTEM.SYSTEM.

– Must be designed to STORE, control and TREAT Must be designed to STORE, control and TREAT runoff generated by one and one-half inch or runoff generated by one and one-half inch or rainfall.rainfall.

Requirements of Structural Requirements of Structural ControlsControls

• Same as Phase IISame as Phase II– Remove an 85% average annual amount of Remove an 85% average annual amount of

Total Suspended SolidsTotal Suspended Solids– For detention ponds – draw down the For detention ponds – draw down the

treatment volume no faster than 48 hours, treatment volume no faster than 48 hours, but no slower than 120 hours.but no slower than 120 hours.

– Discharge volume at a rate = or less than Discharge volume at a rate = or less than pre-development for 1-year, 24-hour storm.pre-development for 1-year, 24-hour storm.

– Meet General Engineering Design Criteria.Meet General Engineering Design Criteria.

Structural Controls and High-Structural Controls and High-Water Table SeparationWater Table Separation

• For controls that require separation from For controls that require separation from seasonal high-water table, a seasonal high-water table, a minimumminimum of of two feet is mandated.two feet is mandated.

• Need 12 inches of naturally occurring soil Need 12 inches of naturally occurring soil above the seasonal high water table with a above the seasonal high water table with a minimum soil hydraulic conductivity of minimum soil hydraulic conductivity of 0.52 inches per hour. 0.52 inches per hour.

Summary – Summary – Permitting Requirements – Permitting Requirements –

Sec. ASec. A• If disturbing more than one acre If disturbing more than one acre

residential or 10,000 sq.ft. non-residential or 10,000 sq.ft. non-residentialresidential– Stormwater permit required andStormwater permit required and– 50-ft. vegetated buffer for new development; 30 50-ft. vegetated buffer for new development; 30

ft. for redevelopmentft. for redevelopment• Definition of vegetated buffer different in Neuse and Definition of vegetated buffer different in Neuse and

Tar-Pam River Basins (can be disturbed; buffer can be a Tar-Pam River Basins (can be disturbed; buffer can be a lawn in Dare County) andlawn in Dare County) and

– No credit for wetlands in computing built-upon No credit for wetlands in computing built-upon area.area.

Summary (con’t) Summary (con’t) - Permitting Requirements- Permitting Requirements

• If < ½ mile from and draining to SA watersIf < ½ mile from and draining to SA waters– No new points of discharge; no increase in flow to SA waters.No new points of discharge; no increase in flow to SA waters.– Level spreaders to diffuse any flow through wetland areasLevel spreaders to diffuse any flow through wetland areas– 12% or less built-upon area = low density12% or less built-upon area = low density

• No engineered stormwater controls required on siteNo engineered stormwater controls required on site• Stormwater must be primarily conveyed by vegetated Stormwater must be primarily conveyed by vegetated

conveyancesconveyances– Greater than 12% built-upon area = high densityGreater than 12% built-upon area = high density

• Structural stormwater controls required or any BMPStructural stormwater controls required or any BMP• For structural controls, minimum separation of 12” of natural For structural controls, minimum separation of 12” of natural

soil above seasonal high water tablesoil above seasonal high water table• Need to control and treat the difference in runoff from pre-Need to control and treat the difference in runoff from pre-

development/post-development one-year 24-hour storm development/post-development one-year 24-hour storm conditions within property boundary.conditions within property boundary.

Summary (con’t)Summary (con’t)- Permitting Requirements- Permitting Requirements

• If > ½ mile from and draining to If > ½ mile from and draining to SA watersSA waters– 24% or less built-upon area = low density24% or less built-upon area = low density

•Stormwater conveyed primarily by vegetated Stormwater conveyed primarily by vegetated conveyancesconveyances

– > 24% built-upon area = high density> 24% built-upon area = high density•Structural engineered controls required or any Structural engineered controls required or any

BMPBMP•Will need to store, control and treat runoff Will need to store, control and treat runoff

from one and one-half inch of rainfall.from one and one-half inch of rainfall.

No Stormwater Permit Needed No Stormwater Permit Needed – –

But Part of the Rules! But Part of the Rules! Sections B and CSections B and C• New residential development with land disturbance New residential development with land disturbance

over 10,000 sq. ft. but less than an acre AND BUA over 10,000 sq. ft. but less than an acre AND BUA is greater than 12% within ½ mile and draining to is greater than 12% within ½ mile and draining to SA waters SA waters

OROR

New residential development with land disturbance New residential development with land disturbance over 10,000 sq. ft. AND BUA is greater than 24% over 10,000 sq. ft. AND BUA is greater than 24%

outside of ½ mile SA waters.outside of ½ mile SA waters.

If lot is part of a larger subdivision that was already If lot is part of a larger subdivision that was already issued a stormwater permit, then you should not issued a stormwater permit, then you should not

have to comply with these rules. (This is not clearly have to comply with these rules. (This is not clearly stated in Sections B and C and needs to be stated in Sections B and C and needs to be

clarified!)clarified!)

Within ½ mile….Within ½ mile….

• Collect all rooftop runoff from one-year 24-hour Collect all rooftop runoff from one-year 24-hour storm in rain barrels or cisterns. All uncovered storm in rain barrels or cisterns. All uncovered areas to be paved need to be constructed of areas to be paved need to be constructed of permeable pavement or other pervious material permeable pavement or other pervious material OR OR

• Direct all rooftop runoff from one-year 24-hour Direct all rooftop runoff from one-year 24-hour storm to a rain garden. All uncovered areas to be storm to a rain garden. All uncovered areas to be paved need to be constructed of permeable paved need to be constructed of permeable pavement or other pervious material ORpavement or other pervious material OR

• Install any other BMP to control and treat the Install any other BMP to control and treat the difference in runoff from pre-development/post difference in runoff from pre-development/post development one-year/24-hour storm conditions.development one-year/24-hour storm conditions.

Outside of ½ mile, ETC.Outside of ½ mile, ETC.

• Collect all rooftop runoff from the first 1.5 inches Collect all rooftop runoff from the first 1.5 inches of rainfall in rain barrels or cisterns. All uncovered of rainfall in rain barrels or cisterns. All uncovered areas to be paved need to be constructed of areas to be paved need to be constructed of permeable pavement or other pervious material permeable pavement or other pervious material OR OR

• Direct all rooftop runoff from the first 1.5 inches Direct all rooftop runoff from the first 1.5 inches of rainfall to a rain garden. All uncovered areas to of rainfall to a rain garden. All uncovered areas to be paved need to be constructed of permeable be paved need to be constructed of permeable pavement or other pervious material ORpavement or other pervious material OR

• Install any other BMP to control and treat the Install any other BMP to control and treat the runoff the first 1.5 inches of rainfall. runoff the first 1.5 inches of rainfall.

CHALLENGES OF RULESCHALLENGES OF RULES• Intent/PurposeIntent/Purpose• DWQ has no statute authority to mandate that local DWQ has no statute authority to mandate that local

governments enforce or monitor sections B and C.governments enforce or monitor sections B and C.• Sections B and C will be self-regulating and compliance Sections B and C will be self-regulating and compliance

will be complaint-driven.will be complaint-driven.• Sections B and C do not specifically exclude lots in Sections B and C do not specifically exclude lots in

subdivisions already under a stormwater permitsubdivisions already under a stormwater permit• As written, under Section A-2-C combined with A-2-B – As written, under Section A-2-C combined with A-2-B –

lots may be unbuildable. lots may be unbuildable. • Official Maps?Official Maps?• Interpretation by local officers?Interpretation by local officers?• Incorporating local rulesIncorporating local rules• Vested Rights?Vested Rights?• COST $$$$COST $$$$

What’s Next?What’s Next?

• Rules go before Rules Review Commission Feb Rules go before Rules Review Commission Feb 2121stst..

• If sent for Legislative ReviewIf sent for Legislative Review– Changes and clarifications may be made.Changes and clarifications may be made.– If no action taken by Committee, rules as presented If no action taken by Committee, rules as presented

become effective August 1, 2008.become effective August 1, 2008.

• Local Cooperation/ControlLocal Cooperation/Control– Lot coverage definition – Can we come up with ONE Lot coverage definition – Can we come up with ONE

county-wide definition?county-wide definition?– Setback Requirements?Setback Requirements?– County-wide USMP?County-wide USMP?

Universal Stormwater Management Universal Stormwater Management Plan (USMP)Plan (USMP)

• Local control of stormwater rulesLocal control of stormwater rules• Supersedes Coastal Stormwater RulesSupersedes Coastal Stormwater Rules• Permitting threshold would be 10,000 Sq. Ft. of Permitting threshold would be 10,000 Sq. Ft. of

land disturbanceland disturbance• Plan would have to meet minimum requirements Plan would have to meet minimum requirements

approved by DWQapproved by DWQ• Permit issued locally – municipality or CountyPermit issued locally – municipality or County• Rule language: Rule language:

http://h2o.enr.state.nc.us/su/documents/Microsofthttp://h2o.enr.state.nc.us/su/documents/MicrosoftWord-USMP-FinalEffectiveRule_.pdfWord-USMP-FinalEffectiveRule_.pdf

• More info: http://h2o.enr.state.nc.us/su/usmp.htmMore info: http://h2o.enr.state.nc.us/su/usmp.htm

Additional info:Additional info:

Division of Water Quality – Tom ReederDivision of Water Quality – Tom ReederEnvironmental Supervisor - 919-733-5083 x Environmental Supervisor - 919-733-5083 x

528 tom.reeder@ncmail.net528 tom.reeder@ncmail.netFAX: 919-733-9612FAX: 919-733-9612

Website on Stormwater Rules: Website on Stormwater Rules: http://h2o.enr.state.nc.us/su/coastal.htmhttp://h2o.enr.state.nc.us/su/coastal.htm

Questions?Questions?

Willo Kelly – Government Affairs DirectorWillo Kelly – Government Affairs DirectorOuter Banks Home Builders AssociationOuter Banks Home Builders Association

Outer Banks Realtors AssociationOuter Banks Realtors Associationwillokelly@gmail.comwillokelly@gmail.com