On a hot South Carolina afternoon, a pond can look calm and harmless until it doesn’t.
The water turns a blue-green color. Livestock continue to drink and wade. Dogs swim. Animals get sick. Families wonder if the water is safe.
Across South Carolina, harmful algal blooms are becoming more common. Often caused by cyanobacteria, sometimes called blue-green algae, these blooms thrive in warm, nutrient-rich water and can appear quickly.
Some blooms create thick mats and foul odors. Others are nearly invisible. But both can be dangerous.
According to the Centers for Disease Control and Prevention, toxins produced by harmful blooms can cause skin irritation, stomach illness, liver damage, neurological problems and, in severe cases, death in people and animals.
For pond owners, farmers and families who spend time around lakes and waterways, the risks are real.
This is where Clemson University researchers and Cooperative Extension Service specialists are stepping in to help communities identify blooms earlier, reduce risks and protect water resources before problems escalate.
Turning concern into action
An important first step is to be aware of changes in water.
“Unusual color changes, surface scums or algal mats forming, are signs that something may be wrong,” said Heather Nix, Clemson Extension Upstate regional water resource agent.
Recent hot temperatures, nutrient runoff and dry weather have created ideal conditions for blooms across South Carolina.
Residents can check conditions on public lakes through the South Carolina Harmful Algal Bloom Monitoring Map or report suspected blooms to the South Carolina Department of Environmental Services.
Steps to prevention
While these blooms occur naturally, Clemson experts say they can be prevented.
The biggest factor is excess nutrients entering the water through fertilizer runoff, sediment and other sources.
“Practical steps such as reducing fertilizer runoff, planting vegetation along shorelines and limiting sediment entering ponds can help reduce the risk of blooms,” said Sarah White, Clemson water quality and treatment specialist.
When harmful blooms are suspected, people should avoid contact with the water and keep pets and livestock away until testing is complete.
South Carolina residents can get help from their local Clemson Extension offices to identify suspicious growth. Samples can also be submitted to the Clemson Plant and Pest Diagnostic Clinic.
The Clemson Home and Garden Information Center provides instructions for collecting samples and conducting simple screening tests.
Additionally, Kendall Kirk, precision agriculture engineer, is developing a WebApp monitoring system designed to identify bloom conditions.
Predicting blooms before they appear
Clemson researchers are also working on ways to detect blooms before they become visible.
Debabrata Sahoo, Clemson water resources engineer, is leading a research project funded by the U.S. Army Engineer Research and Development Center Environmental Laboratory.
The project is focused on developing an artificial intelligence-powered surveillance system capable of detecting bloom conditions early, sometimes before blooms are visible.
The system combines water-quality data, mapping technology and predictive modeling to track conditions linked to algal growth. Eventually, it could alert water managers and landowners when blooms may be developing, giving them time to respond sooner.
Sahoo expects the system to be available within two years.
Supporting South Carolina communities
Clemson Extension offers programs statewide focused on water quality, conservation and land management, helping residents, farmers and local communities protect South Carolina’s water resources.
From pond management training to youth environmental education programs, the goal is simple: to give people the knowledge and tools they need to keep waterways healthy and safe.
