Carolina Green: Campus seeks
to stop soil erosion

Rapid growth and construction throughout the Triangle in recent years has increased the amount of sediment entering area streams and lakes. In many water bodies the benthic, or bottom dwelling, life has been smothered completely. State regulations do not require erosion control measures until a construction site exceeds five acres in size. Tighter federal water quality standards that discourage sediment loading will come into effect in spring 2003.

At Carolina, a University-driven erosion and sediment control (ESC) plan was developed this year by the Environment, Health & Safety Department. Environmental specialist Sharon Myers obtained input from campus faculty and surveyed best practices employed elsewhere. The best management practices called for in the plan will be incorporated in all future capital projects, regardless of their size. They will apply to the sites for new buildings, roads and utilities. The plans are further evidence of the University’s commitment to agreements made with the town regarding the Development Plan.

Similar to a tree protection plan, the erosion and sediment control plan will assess the challenges and the control measures required at each prospective building site. Identifying areas with a high susceptibility to erosion, limiting disturbance on steep slopes and restricting clearing to only those areas necessary for construction are critical components of the strategy.

Reducing the length of time an area is exposed substantially reduces the risk of erosion. At Carolina, contractors will be required to cover areas unworked for seven days with straw mulch or other means. Straw mulch is a cost-effective control strategy that reduces sediment concentrations in runoff by more than 90 percent. Areas unworked for 30 days must be planted.

An erosion and sediment control coordinator, designated by the project contractor, will be responsible for daily maintenance and review of adopted site measures. Keeping soil in place on a construction site is important because once the soil is “entrained” in stormwater, it is virtually impossible to remove completely. Even partial removal is a costly challenge. Fortunately, the logging mats used to protect campus trees also assist in keeping soil intact.

The Sonja Haynes Stone Black Cultural Center on South Road is the first campus project to incorporate an improved erosion and sediment control plan. The building site is on a slope directly adjacent to Meeting of the Waters Creek. Turbidity and other environmental variables in the creek are already measured by an electronic monitoring station. Data is downloaded daily and published for all to see at www.ehs.unc.edu/environmental/water_quality

Erosion and sediment control reviews have also been conducted for several additional projects. In the future, all capital projects, regardless of their size, will incorporate an erosion and sediment control plan.

Sponsored by Facilities Services
Writer: Cindy Pollock Shea, sustainability coordinator

University GazettUniversity Gazettee