Alcovy Watershed Protection Plan

Four counties – Walton, Newton, Jasper and Gwinnett – and thirteen municipalities within those counties hired environmental consultants Brown and Caldwell to develop a comprehensive watershed assessment plan, required under state law before a local government can increase the amount of water it withdraws or wastewater it discharges into the rivers of the state.

The UGA Office of Public Service and Outreach was hired as a subcontractor to oversee the public involvement program of the assessment and the development of an implementation plan to assure watershed protection in the future.

Hundreds of citizens were reached as a result. In addition to the normal public meeting forums, which are often poorly attended, we took a slide show about the Alcovy project on the road to where the citizens were. We sent out a letter describing the project and asking for an opportunity to share and solicit input to over 200 civic, church, and environmental groups in the watershed. Around thirty responded and invited us to present to their homebuilders associations, Sierra Club chapters, cattlemen associations, etc. Input from these meetings substantially shaped the recommendations we made regarding implementation.

Modeling showed that if the counties within the watershed grow at the rate projected in their comprehensive plans, and only implement watershed protection strategies mandated by the state, they will substantially exceed water quality standards for many pollutants by the year 2030.

The BASINS hydrologic model was used to determine how conservation subdivisions, riparian buffers, stormwater ordinances and other tools would affect water quality as the Alcovy Basin develops over the next 20 years. Modeling showed that a stormwater ordinance was the single most effective tool for preventing water quality degradation. To be effective, the ordinance must provide incentives for minimizing impervious surface and include water quality standards. The best way to prevent water quality degradation from a high level of development, however, is to combine a stormwater ordinance with a combination of tools, such as stormwater management ordinances, riparian buffers, conservation subdivisions, improving erosion and sedimentation programs, they could continue to grow AND meet water quality objectives.

In the final report to our clients, we included detailed information about each of these land use planning tools, model ordinances, recommendations for funding the implementation, etc. We recommended a suite of tools to each county; and of course the recommendations varied according to the population, planning expertise and political will of each of the counties.

Though the Watershed Assessment Project is complete, we continue to work with Gwinnett County and Covington under other contracts to protect the Alcovy watershed.

Alcovy Watershed
chart

Amount of total phosphorus, a common aquatic pollutant, in the Alcovy River under current (2000) conditions, projected conditions in 2020 without additional growth management policies, and 2020 conditions with various policies in place. These data were generated by Limnotech, Inc., Brown and Caldwell, Inc. and the Institute of Ecology using the BASINS model as part of the Alcovy Watershed Protection Project. “Cons. Sub.” indicates the use of a conservation subdivision ordinance; “Rip. Buffers” a riparian buffer ordinance; “Better E&S Control” represents a well-enforced erosion and sedimentation control ordinance; and “Stormwater” is a comprehensive stormwater management ordinance that includes incentives for reducing impervious surfaces along with water quality control requirements. “All” is a combination of all policies.