1 Linking Land Use and Water Quality: Guiding Development Surrounding Durham County’s Drinking Watershed

Abstract Linking Land Use and Water Quality: Guiding Development Surrounding Durham County’s Drinking Watershed

By Katie Rose Levin May 2012

Cities and Counties have an obligation to provide water to their citizens in the quality and quantity necessary to support a viable existence. To meet these demands, in 1929 Durham City dammed the Flat River, creating the reservoir named “Lake Michie” in the far north eastern part of Durham County. Although located in a primarily rural area, there are signs that stormwater runoff is having detrimental effects on Lake Michie. The reservoir has already lost a quarter of its holding capacity to sedimentation, and was recently classified as Eutrophic by the USGS. Development pressure will only increase, as for the last ten years Durham County’s population has grown faster than the average across the state.

To address development concerns, Durham county and city created the Unified Development Ordinance (UDO) which provides enhanced protection for the land in the Lake Michie Watershed. The UDO limits the amount of impervious surface allowed on any one parcel in the watershed to 6%, while allowing a transfer of development between parcels to discourage urban sprawl. In addition to the protection afforded by codes, Durham managers are interested in creating a unified conservation scheme, based on preserving parcels as forested areas.

This Project provides information and maps that can be used for conservation planning. Through combining topography, soils, and land use, areas likely to have highest impact on water quality are highlighted. Using this information, parcels can be evaluated based on their relative impact on water quality. Likewise, parcels can be compared against each other for the relative impact they have on water quality, informing transfers of impervious surface areas to meet development code. By combining the scientific evaluation of land use effects with the political boundaries of parcel ownership officials can easily translate science into the politics of conservation and development. Just like the New Hope Creek and Eno River conservation maps, now Lake Michie has a scientifically based conservation map to help officials and land managers preserve water quality into the future.

Adviser: Dr. Dean Urban