What’s going on with Greenfield Lake?: UNCW marine biologist explains

WILMINGTON, NC (WWAY) — If you’ve visited Greenfield Lake recently, you may have noticed a large algae bloom.  

Amy Grogan of UNCW’s Aquatic Ecology Lab studies the lake and works with the city to help address the algae blooms.  

While the algae isn’t directly harmful to wildlife, Grogan noted blooms of this magnitude are not natural for the lake, and that one of the biggest contributing problems is stormwater runoff.   

Grogan explains that nutrients like phosphorus and nitrogen flow into the lake from the surrounding neighborhoods, causing algae levels to occasionally spike. 

“Greenfield Lake has, like I said, a lot of storm water outfall that comes into it, and there also a lot of branches or small creeks that enter the lake, and those creeks make their way through the urban environment and become very polluted,” she said. 

Grogan adds that while reactive measures like removing some of the algae carpeted on the surface can help, the best way to reduce algae is addressing the problem before it starts. She said responsible development that ensures the health of the local ecosystem, like artificial wetlands can be the first step in reducing runoff pollution.