North Carolina Administrative Code › Title 15A - Environmental Quality › Chapter 02 - Environmental Management › Subchapter B - SURFACE WATER AND WETLAND STANDARDS › Section .0600 - WATER QUALITY MANAGEMENT PLANS › Section 02B .0624 - WATER SUPPLY WATERSHED PROTECTION PROGRAM: NONPOINT SOURCE AND STORMWATER POLLUTION CONTROL

Current through Register Vol. 39, No. 2, July 15, 2024
This Rule sets forth requirements for projects that are
					 subject to water supply watershed regulations.
(1) Implementing Authority. The requirements
				  of this Rule shall be implemented by local governments with land use authority
				  in one or more designated water supply watersheds. State agencies shall also
				  comply with this Rule insofar as required by
				  G.S.
				  143-214.5 and in accordance with Rule .0622
				  of this Section.
(2) APPLICABILITY.
				  This Rule shall apply to all new development projects, including state owned
				  projects, that lie within a designated water supply watershed, except in a
				  Class WS-IV watershed where this Rule applies only to new development projects
				  that require an Erosion and Sedimentation Control Plan. Rule .0622 of this
				  Section includes project types to which rules do not apply.
(3) PROJECT DENSITY. The following maximum
				  allowable project densities and minimum lot sizes shall apply to a project
				  according to the classification of the water supply watershed where it is
				  located, its relative location in the watershed, its project density, and the
				  type of development:
Water Supply Classification
Location in the Watershed
Maximum Allowable Project Density or Minimum Lot
								Size
Low Density Development
High Density Development
Single-family detached residential
Non-residential and all other residential
All types
WS-I
Not Applicable: Watershed shall remain undeveloped
								except for the following uses when they cannot be avoided: power transmission
								lines, restricted access roads, and structures associated with water
								withdrawal, treatment, and distribution of the WS-I water. Built-upon area
								shall be designed and located to minimize stormwater runoff impact to receiving
								waters.
WS-II
Critical Area
1 dwelling unit per 2 acres or 80,000 square foot
								lot excluding roadway right-of-way or 6% built-upon area
6% built-upon area
6 to 24% built-upon area
Balance of Watershed
1 dwelling unit per 1 acre or 40,000 square foot
								lot excluding roadway right-of-way or 12% built-upon area
12% built-upon area
12 to 30% built-upon area
WS-III
Critical Area
1 dwelling unit per 1 acre or 40,000 square foot
								lot excluding roadway right-of-way or 12% built-upon area
12% built-upon area
12 to 30% built-upon area
Balance of Watershed
1 dwelling unit per one-half acre or 20,000 square
								foot lot excluding roadway right-of-way or 24% built-upon area
24% built-upon area
24 to 50% built-upon area
WS-IV
Critical Area
2 dwelling units per acre or 20,000 square foot lot
								excluding roadway right-of-way or 24% built-upon area
24% built-upon area
24 to 50% built-upon area
Protected Area
2 dwelling units per acre or 20,000 square foot lot
								excluding roadway right-of-way or 24% built-upon; or 3 dwelling units per acre
								or 36% built-upon area without curb and gutter street system
24% built-upon area; or 36% built-upon area without
								curb and gutter street system
24 to 70% built-upon area
WS-V
Not Applicable
(4) CALCULATION OF PROJECT DENSITY. The
				  following requirements shall apply to the calculation of project density:
(a) Project density shall be calculated as
				  the total built-upon area divided by the total project area;
(b) A project with "existing development," as
				  that term is defined in Rule .0621 of this Section, may use the calculation
				  method in Sub-Item (a) of this Item or may calculate project density as the
				  difference of total built-upon area minus existing built-upon area divided by
				  the difference of total project area minus existing built-upon area. Expansions
				  to existing development shall be subject to this Rule except as excluded in
				  Rule .0622(1)(d) of this Section. Where there is a net increase of built-upon
				  area, only the area of net increase shall be subject to this Rule. Where
				  existing development is being replaced with new built-upon area, and there is a
				  net increase of built-upon area, only the area of net increase shall be subject
				  to this Rule;
(c) Total project
				  area shall exclude the following:
(i) areas
				  below the Normal High Water Line (NHWL); and
(ii) areas defined as "coastal wetlands"
				  pursuant to
				  15A NCAC
				  07H .0205, herein incorporated by reference,
				  including subsequent amendments and editions, and available at no cost at
http://reports.oah.state.nc.us/ncac.asp
,
				  as measured landward from the NHWL; and
(d) Projects under a common plan of
				  development shall be considered as a single project for purposes of density
				  calculation except that on a case-by-case basis, local governments may allow
				  projects to be considered to have both high and low density areas based on one
				  or more of the following criteria:
(i)
				  natural drainage area boundaries;
(ii) variations in land use throughout the
				  project; or
(iii) construction
				  phasing.