New report reveals troubling water quality trends in Old Tampa Bay

The results of a recent study by the Tampa Bay Estuary Program revealed some concerning trends regarding levels of algae known for posing a health risk to wildlife and people.

Reducing the levels of Pyrodinium bahamense has been a recurring challenge for water quality managers over the years.

However, According to a new report, while other bays reported algae levels below target criteria, Old Tampa Bay did not.

Some of the data collection was inhibited by COVID-19, however, water quality experts say this is still concerning because algae in the water column can cause shading and die-offs of seagrass and seagrass is the foundation of a healthy bay.

Also, harmful algal blooms can deprive the water of oxygen, leading to fish kills and impacts on the whole ecosystem. 

"Once it is present in a water body it produces cysts that fall to the bay bottom and rest in the sand and sediment. These cysts act like seed banks for future bloom development. The cysts germinate and begin to grow mostly as the temperatures begin warming up in the springtime. They are able to capitalize on a variety of food sources (nutrients) and thrive in areas with poor circulation (like Old Tampa Bay)," says Maya Burke, Assistant Director for Tampa Bay Estuary Program.

To date, bay managers have focused their efforts on continuing to reduce nutrient pollution to the affected portion of the bay. However, those efforts haven’t been enough to control blooms of Pyrodinium in Old Tampa Bay.

Now, bay managers are exploring new options to address the issue. This includes improving circulation in the bay by altering the causeways on the Courtney Campbell, Howard Frankland, and Gandy bridges. Another option is utilizing oysters and clams to consume and remove the algae from the bay. Also, whether restoring more natural freshwater flows from tidal creeks and canals could prove to be effective.

You can read the full report at