Secondary and Cumulative Impacts Master Management Plan - 2014

APPENDIX B – WAKE COUNTY PROGRAMS TO MITIGATE SECONDARY AND CUMULATIVE IMPACTS

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. 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

Stormwater and Impervious Surface Limits (UDO Article 9 and Article 5)

B-2