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APPENDIX B – WAKE COUNTY PROGRAMS TO MITIGATE SECONDARY AND CUMULATIVE IMPACTS
B-2
of the potential SCI discussed in Section 5 of the Town’s SCIMMP. Only programs
affecting to the Planning Area are discussed not all portions of Wake County.
B.1
Local Regulations and Programs
Environmental protection is a cornerstone value in the County. The County has
developed several programs to meet its internal goals for providing a high-quality life
for its residents. To meet those goals, the County established a Consolidated Open Space
Plan that includes protection of important habitat areas, growth management strategy to
protect water quality, and land use plans that encourage growth in certain areas and
discourage growth in other areas. The County also revised its ordinances to modify its
cluster and open space development provisions to encourage the preservation of more
open space around environmentally sensitive areas within new residential
developments. These regulations don’t allow for higher densities than that allowed by
the zoning district—instead they allow for lot sizes to be reduced below the standard
requirement with the land “saved” by the reduced lot size being preserved as open
space—for example in R-40W instead of creating 40,000 square-foot lots, the developer
can create 20,000 square-foot lots with the 20,000 square-foot difference being preserved
as open space. In addition, the County developed a riparian protection program,
floodplain program, erosion and sediment control program, and stormwater program to
protect water quality and in-stream habitat. Table B-1 summarizes the programs that
impact development procedures. Table B-2 illustrates the environmental resources that
the various programs protect.
TABLE B-1
Summary of Selected Wake County UDO Protection Measures
Program
Summary
Erosion and
Sediment
Control
(UDO Article 10)
An erosion and sediment control permit is required for land disturbing activity over 1 acre.
Silt fences and construction entrances are required on all sites, even those that are less
than 1 acre.
Sediment basins (sized according to drainage area), silt fencing, perimeter ditches, and/or
other approved measures are required to control sediment from development activity.
Soil stabilization by establishing a grass cover or mulching and tacking must occur within
the current NCDENR stabilization timeframes.
Plans to identify areas subject to severe erosion, limit time of exposure, and limit exposed
area are required.
Land disturbance in proximity to a lake or natural water course requires an undisturbed
50-foot-wide buffer, provided that the undisturbed zone is of sufficient width to confine
visible siltation within the first 20 feet.
Encourages contractor education and training related to erosion and sediment control.
Stormwater and
Impervious
Surface Limits
(UDO Article 9
and Article 5)
Post-development site runoff curve number for residential development may not exceed
target curve numbers contained in Article 9, Part 2 of the UDO based on precipitation
depth of 3 inches over a 24-hour period. Stored water must be drained over a period of not
less than 2 days or more than 5 days.
Stormwater credit system provides incentives for better site design and locating new
development that causes less impact to aquatic resources. Approved methods include:
disconnected impervious surfaces, reforestation, and cluster and open space subdivisions.
Practices reduce generation of stormwater as well as size and cost of stormwater storage,
and provide partial removal of pollutants.
Impervious surface limits in water supply watersheds range from 6 to 30percent for
residential areas and up to 30 percent for non-residential areas. Stormwater best