Vertical Profiling Safeguards Drinking Water and Sheds Light on Cyanobacteria

Abstract

This report discusses a search for algal toxins in North Carolina reservoirs that evolved into an ongoing early warning system for three important drinking water reservoirs that serve two large cities. The search also yielded a greater understanding of the dynamics of blue‐green algae, or cyanobacteria, in the state's reservoir system. Building on a pair of grants from the Centers for Disease Control and Prevention (CDC) to explore key reservoirs for cyanotoxins, the Center for Applied Aquatic Ecology (CAAE), directed by JoAnn Burkholder at North Carolina State University in Raleigh, teamed up with the North Carolina cities of Raleigh and High Point to track cyanobacteria blooms throughout the water column. On the basis of continuous in situ water quality monitoring of the water column near the intake structures in three reservoirs, treatment plant operators can vary the depth at which they draw water into their plants, avoiding cyanobacteria blooms that can introduce toxins or affect taste and odor. The in situ data as well as manually collected measurements and grab samples also provide insight about the effect of weather and land use on cyanobacteria.