Water quality concerns come to fore

Chemicals in area streams could soon translate into both a health hazard and a greater financial burden for local municipalities.

High levels of phosphorous and especially nitrogen have led the N.C. Division of Water Quality to propose a plan, designed to comply with federal and state requirements, that would call for sharp reductions of the pollutants in the New Hope arm of Jordan Lake.

The New Hope arm is the area of the lake to which all water in the Chapel Hill-Carrboro area eventually drains.

The regulations — which call for a 35 percent reduction in nitrogen and a 5 percent drop in phosphorous — were presented to the Carrboro Board of Aldermen on Tuesday and will be given to the Chapel Hill Town Council tonight.

The foundation for the reductions should be in place by 2015.

A major part of the problem, said Chapel Hill’s storm water management engineer, Fred Royal, is that the increased chemicals act as nutrients to certain species of algae, leading them to grow rapidly and triggering blooms that kill other organisms.

“It removes oxygen for the water, or has that potential,” he said. “The bottom line, it’s toxic to fish.”

The chemicals also harm water quality for human use.

“The water quality aspect for human use becomes a health hazard,” Royal said.

Ed Holland, Orange Water and Sewer Authority’s planning director, also emphasized the nutrients’ potential impact on humans.

“Jordan Lake is kind of a regional resource that everybody uses. It’s used for drinking water downstream — we might have to drink from Jordan Lake in the future,” Holland said.

Officials say the pollution comes from both point sources, or identifiable points of origin, and less centralized nonpoint sources. An example of the former is the OWASA plant on Jones Ferry Road in Carrboro, while nonpoint sources include chemicals applied to yards and farm fields.

There are already some efforts under way to limit pollutants.

Carrboro soon will undertake a plan to label storm drains, and the OWASA plant is implementing a $50 million improvement project that will include additional water filters.

Holland said the filters should provide some reduction in phosphorous and a significant reduction in nitrogen.

Royal also said Chapel Hill’s Land Use Management Ordinance works to improve water quality through requirements such as limits on the use of impervious surfaces. Carrboro has a similar regulation.

Another important piece of the water quality puzzle is land conservation. Recently, local municipalities have purchased land to preserve undeveloped areas.

The county’s Lands Legacy Program is perhaps the most successful of those efforts.

In fact, water quality was one of the key issues cited when four local municipalities and the Triangle Land Conservancy came together to execute a complex land deal along Erwin Road.

The land, located along New Hope Creek, was slated to be sold by Duke University to a developer.

“That’s a huge part of it,” said Royal. “The more open space you have to work with … the better off we’ll be.”

Noah Ranells, Carrboro’s environmental planner, said the town is working to prioritize stream conservation practices that the N.C. Ecosystem Enhancement Program suggested in February for Morgan and Little creeks, which run through the town.

Open space and permeable surfaces help improve water quality because as water seeps through the ground or flows along undisturbed streams, impurities are stripped, leaving the water far purer than if it flowed the same distance over concrete.

But officials agree that more needs to be done, especially with older developments.

Division of Water Quality Planning Section Chief Alan Clark said gains are more difficult and expensive to realize in urban environments such as the one that drains to the New Hope arm of the lake.

“What that means is we would need to get a 35 percent reduction (in nitrogen) from developed areas, which means retrofitting, which is obviously very expensive,” Clark said.

He said retrofitting would mean ensuring that already developed properties acquire pollution-fighting features such as sand-filled trenches around parking lots.

He added that the financial burden for such changes would probably fall to local municipalities but might be offset by grants or state funding.

In addition to retrofitting, Royal also emphasized that local governments would need to work together to solve the problem.

“It’s not just Chapel Hill. The city of Durham’s got the same challenge, the town of Carrboro, the University — everybody,” he said.

“Everybody’s involved.”

Contact the City Editor at citydesk@unc.edu.