Conservation
Cleaning up Jordan Lake
May 2006
The May 10th program meeting brought together three experts on the state’s efforts to clean up the nutrient pollution in Jordan Lake.
First, Elaine Chiosso, Executive Director of the Haw River Assembly, discussed the factors that make the lake vulnerable to nutrient pollution. Data analysis suggests that one third of the excess nitrogen and phosphorus comes from point sources such as water treatment plants, two thirds from nonpoint sources such as runoff from land populated by about 900,000 people. The point sources are already being addressed, with improved plants in Greensboro, Chapel Hill, and Durham. Problems still to be reckoned with include old leaking pipes going into the plants, aging septic systems, and the new spray irrigation systems slated to be built in the new developments approved by Chatham County. The shape of the lake is another factor contributing to the shape it’s in—it has two arms, the Haw River arm and the New Hope arm, which moves much more slowly (it takes over a year for water to move through it as opposed to 5 days for the Haw arm). It is not surprising that the recent fish kills in March of 2006) took place in the New Hope arm of the lake.
Next, Joe Rudek, senior scientist with Environmental Defense, explained how excess nutrients kill fish: Excess nutrients foster the growth of excess algae (some of which are poisonous). As algae die, they sink to the bottom; as they rot, they consume oxygen, which can result in areas where oxygen levels are too low for fish and other organisms to survive. Rudek then outlined a number of techniques that can slow runoff from developed land, thus allowing more nutrients to be absorbed before the water drains into sewers, streams, and, ultimately, the lake. These include riparian (vegetative) buffers for streams and rivers, swales, rain gardens, and porous pavements.
Amy Pickle, attorney with the Southern Environmental Law Center, detailed the legal framework for the new rules being written by the North Carolina Environmental Management Commission, including several federal and state laws. In 1983, almost immediately after the dam was closed to form the lake, the lake was declared nutrient sensitive. In 2002, the Upper New Arm was declared impaired. When a lake is considered impaired because 10% of samples don’t meet the standards, the federal government fixes a Total Maximum Daily Load (TMDL) to establish a limit on the nutrients an area will be allowed to contribute. In 2003, the Division of Water Quality set targets for reduction. The target for the Upper New Hope arm was 35% reduction in N and 5% reduction in P. The target for the Haw arm was 8% reduction in N and 5% in P. The year 2003 also saw the convening of the Jordan Lake stakeholders and the beginning of the process by which the EMC is writing the new rules for inhabitants of the lake’s watershed to achieve those reductions.
According to the most recent schedule, in the spring of 2007, there will be a public comment period on the draft of the rules, with final approval by the state legislature in 2008. Among the methods for achieving the required reductions:
Training for farmers and landscapers on the application of fertilizers, a strengthening of requirements for riparian (vegetative) buffers and other storm water structures described earlier by Joe Rudek for new developments, and retrofits for existing developments
Discussion included some of the complexities of attempts at amelioration, for instance what happens if you control one substance more effectively than another and change the balance in the ecosystem, how many different weather conditions can be reflected in the predictive studies, and whether or not conditions could change by the time the new rules were implemented. Talk also broached the possible role of the Rules Review Commission and how the state will balance the pressure for new development with the drive to clean up the lake.
Armed with information like that offered by the panel, Sierra Club members will be ready to make public comments that could support efforts to clean up Jordan Lake.
— Report by Judith Ferster and May Becker
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