Algae Blooms in Lake Norman Threaten Local Ecosystems

7/10/25 News 1 min read

PreMiEr researcher Dr. Sandra Clinton of UNC Charlotte speaks with WFAE about the surge of harmful algal blooms at Lake Norman, driven by warm temperatures and fertilizer runoff, and the risks cyanobacteria pose to people, pets, and local ecosystems.

Duke Chapel — Algae Blooms in Lake Norman Threaten Local Ecosystems

Harmful algal blooms are on the rise at Lake Norman, with more than 80 blooms reported since the beginning of June 2025, according to the NC Division of Water Resources. Warm water temperatures and fertilizer runoff are the primary drivers. PreMiEr researcher Dr. Sandra Clinton, a professor of geography and earth science at UNC Charlotte, was interviewed by WFAE on the growing threat. “Often when we talk about the harmful algal blooms, or toxic algae, we’re talking about the cyanobacteria,” said Clinton. “Some of these cyanobacteria make what we call cytotoxins. They can be harmful … when they’re high in concentration.” Even nontoxic algae cause ecosystem disruption by depleting oxygen in the water, leading to fish kills. A No Swim Advisory was issued for parts of the lake. Residents and visitors are urged to avoid green or blue-green water and to keep pets away.