Currently underway, the Lake Okeechobee System Operating Manual (LOSOM) planning effort intends to change how water is managed for Lake Okeechobee. A specific topic of interest is understanding how the different water management schemes will affect the risk of algal bloom formation and transport within the Caloosahatchee and St Lucie estuaries. This metric is important to reduce the potential risk of HABs within our local waters which can lead to primary effects—fish kills and human health impacts—and secondary issues, such as environmental degradation and negative impacts on the local economy.
To evaluate algal bloom risk to the estuaries, the U.S. Army Corps of Engineers (USACE) will compare discharges from Lake Okeechobee during the time of the year where algal bloom potential is highest (June – August). This evaluation is based on the concept of moving water with algae from Lake Okeechobee along the C-43 canal to the Caloosahatchee estuary. Based on the available data, an algal biomass transport hypothesis from the lake to the estuary does not paint the entire picture. Other processes contribute to algae bloom formation and transport within the Okeechobee-Caloosahatchee system.
As part of the LOSOM planning effort, SCCF provided these recommendations: developing a more robust monitoring network to assess changes in algae; evaluating algal bloom potential relative to the amount of time water moves from the lake to the estuary; and including other factors, such as temperature and light availability. Ultimately, our goal is to develop an operations plan that reduces the risk of algal blooms in the estuaries and balances the needs of the Caloosahatchee and St Lucie estuaries, Lake Okeechobee, and the Southern Everglades to improve the ecology and sustainability of our system.
By evaluating the existing science, assessing the LOSOM alternatives, and studying nutrient loading from Lake Okeechobee and the upstream basin and the resulting loads to the estuary, we are gaining a better understanding of algal dynamics within the Okeechobee-Caloosahatchee system. As water management changes for Lake Okeechobee, we continue to develop our understanding of algal and nutrient dynamics to inform management and policy decisions.
Hydrologic Modeler Paul Julian’s position is funded jointly by SCCF and The Conservancy of Southwest Florida.