8.5.4 Riparian Buffers Protected | Durham Unified Development Ordinance

This section shall apply to any activity conducted within any riparian buffer, and to any activity conducted outside of any riparian buffer that has hydrologic impacts upon that buffer in violation of the diffuse flow requirements of paragraph 8.5.5, Diffuse Flow Requirements. There is no disturbed area minimum for regulated activities and they include but are not limited to activities conducted pursuant to building permits. As stated in paragraph 8.5.2, Applicability, compliance with this entire section is required even where State standards are less stringent. Within the Neuse River Basin, final review by the City or County shall occur after any State action is completed.

a. Riparian buffers as depicted on the table below shall be required adjacent to the following surface waters: intermittent streams; perennial streams; modified natural streams; lakes; and ponds including beaver ponds.

b. The table includes the additional buffer width required for certain surface waters in watershed protection overlays. It does not include the 10-foot setback required under paragraph 8.5.9C below.

c. A lake or pond shall receive the same buffer as the stream to which it is connected at the point of initial connection.

d. A gap of 300 feet or less in a stream, as determined by the City or County, shall receive the same buffer as the upstream portion of such stream, including culverted or piped streams approved and installed after the effective dates listed in paragraph 8.5.4C.3.a.

Commentary: UDO Sec. 17.3, Defined Terms, defines “adjacent” as “[p]roperty abutting directly on the boundary of, touching, or sharing a common point.” The applicable state rules define “modified natural stream” as “an on-site channelization or relocation of a stream channel and subsequent relocation of the intermittent or perennial flow as evidenced by topographic alterations in the immediate watershed. A modified natural stream must have the typical biological, hydrological, and physical characteristics commonly associated with the conveyance of water.”

Key:
P – Perennial
I – Intermittent
NA – Not applicable because not located therein
M/LR-A – Lake Michie/Little River Critical Area
M/LR-B – Lake Michie/Little River Protected Area
E-A, E-A(2) – Eno River Critical Area
E-B – Eno River Protected Area
F/J-A – Falls/Jordan Critical Area
F/J-B – Falls/Jordan Protected Area

Tier	Watershed Protection Overlay
	None		M/LR-A		M/LR-B		E-A, E-A(2)		E-B		F/J-A		F/J-B
Downtown and Compact Neighborhood
Stream Type	P	I	P	I	P	I	P	I	P	I	P	I	P	I
Width	50	50	NA	NA	NA	NA	NA	NA	NA	NA	NA	NA	100	50¹
Urban
Stream Type	P	I	P	I	P	I	P	I	P	I	P	I	P	I
Width	50	50	NA	NA	NA	NA	NA	NA	100	50¹	NA	NA	100	50¹
Suburban
Stream Type	P	I	P	I	P	I	P	I	P	I	P	I	P	I
Width	50	50	150	50	150	50	150	50	100	50¹	150	100	100	50¹
Rural
Stream Type	P	I	P	I	P	I	P	I	P	I	P	I	P	I
Width	50	50	150	50	150	50	NA	NA	100	50¹	150	100	100	50¹

1Stream buffer minimum of 100 feet if a high density option is utilized per paragraph 8.7.2B.1

Riparian buffers shall be required adjacent to reservoirs pursuant to Sec. 8.6, Water Supply Reservoir Buffer.

Riparian buffers shall be required adjacent to wetlands pursuant to Sec. 8.9, Wetlands Protection Standards.

4. Wetlands adjacent to, or within 50 feet of, surface waters shall be considered part of the riparian buffers but are regulated pursuant to 15A NCAC 2B .0230 and .0231, 15A NCAC 2H .0500, 15A NCAC 2H .1300, and Sections 401 and 404 of the Federal Water Pollution Control Act.

Riparian buffers shall be measured as follows:

1. For intermittent and perennial streams, begin at the top of the bank and extend landward the required distance on all sides of the surface water, measured horizontally on a line perpendicular to a vertical line marking the top of the bank.

2. For ponds, lakes and reservoirs located within a natural drainage way, begin at the normal water level and extend landward the required distance, measured horizontally on a line perpendicular to a vertical line marking the normal water level.

3. Where an intermittent or perennial stream begins or ends, including but not limited to when it goes underground, enters or exits a culvert, or enters or exits a wetland, begin at the top of the bank and extend landward the required distance in a radius around the beginning or end.

a. The radius requirement shall apply to culverts or piping present within the riparian buffer as of July 22, 1997 within the Neuse River Basin, or as of the effective date of this section (November 4, 2010 for the City; November 8, 2010 for the County) outside of the Neuse River Basin, and has continued to exist since that time.

b. Paragraph 8.5.8, Piping Streams, shall apply to culverts or piping that were approved and installed after such effective dates.

4. Where an intermittent, perennial, or modified natural stream contains a gap of 300 feet or less, as determined by the City or County, extend the upstream buffer in a straight line through the gap, or in an alternative manner if approved by the Planning Director or designee, until it meets the downstream buffer. This shall include culverted or piped streams approved and installed after the effective dates listed in paragraph 8.5.4C.3.a.

1. Riparian buffers shall be clearly indicated on all development plans, site plans, preliminary plats, final plats, sedimentation and erosion control plans, any other plans required before, during, or after construction, and any other documents as required under applicable law or policy.

2. Signs or other mechanisms that clearly demarcate riparian buffer boundaries shall be required for all new development or redevelopment.

a. Temporary signs shall be installed before clearing and grading begins and maintained until permanent signs are installed. Tree save or silt fencing may be used in lieu of temporary signs with prior approval from the City or County as appropriate.

b. Permanent signs shall be installed prior to issuance of certificate of occupancy and maintained in perpetuity.

c. All signs shall be posted at intervals of one per parcel or every 50 feet, whichever is less.

d. Each sign shall be [at least, City only] four inches by six inches in size, shall face away from the buffer, and shall read “Riparian Buffer – Do Not Disturb Except as Authorized by the City [County] of Durham”.

e. All signs must be placed on metal or wood posts installed securely in the ground, except that permanent signs may be placed on permanent fencing along the buffer boundary. If wood posts are used they must be at least two inches by two inches in size and be made of treated wood. Posts must extend a minimum of three feet above ground and be sunk at least two feet below ground.