What is it? 

Lake Okeechobee is Florida’s largest lake and the eighth largest in the United States. The name comes from the Seminole language – “oki” means water and “chubi” means big. Located south of Orlando, the lake has three main tributaries that flow into it, including Fisheating Creek, Taylor Creek, and the Kissimmee River. Water from the lake is discharged through the St. Lucie and Caloosahatchee Rivers, which connect the lake to the Atlantic Ocean and Gulf of Mexico, respectively.  

The lake and its surrounding wetlands are part of the Greater Everglades watershed. The lake and wetlands are a critical component of South Florida’s flood control system which protects surrounding communities during tropical storms and hurricanes. 

Why it matters 

Over the past 30 years, Lake Okeechobee has faced rising levels of nutrient contamination, primarily from agricultural runoff, which has put a strain on the local habitats and residing organisms. This is a particularly concerning situation because the lake makes up a significant portion of South Florida’s water supply. 

Lake Okeechobee has a rich history of hurricane preparedness. It endured a Category 5 hurricane in 1928, causing over 2,500 deaths—the second deadliest in U.S. history. 

Following the Okeechobee Hurricane and massive flooding in 1947, the Herbert Hoover Dike was constructed to manage flooding, and the Okeechobee Flood Control District was established. This district later became the South Florida Water Management District which is still active today, overseeing flood control, water quality, and water conservation. 

Lake Okeechobee was transformed from a natural lake into a managed reservoir to regulate water levels and prevent flooding after hurricanes or heavy rainfall. Researchers at Florida Atlantic University have found that nitrogen from human waste and fertilizers, combined with increased rainfall, is directly tied to elevated nutrient levels in Lake Okeechobee’s waters. These pose a problem in South Florida which sees around 45 to 60 inches of rain per year and is home to more than 6.4 million people. 

The management of this lake allows artificial changes in lake levels to prevent flooding and maintain water supply. However, the output from the lake flows directly into the Everglades and the St. Lucie and the Caloosahatchee estuaries, carrying high concentrations of nitrogen, phosphorus, and ammonia—elements commonly found in fertilizers and human waste. When released into greater ecosystems such as the Everglades, cyanobacteria thrive, triggering harmful algal blooms that threaten aquatic life and water quality. 

What you can do 

Lake Okeechobee is a landmark of Florida, home to countless native species, and an important heritage site for local communities and Florida Native American tribes. It currently faces severe water quality issues and recently ranked top of the list as the most polluted lake in the United States. 

The South Florida Water Management District currently has many projects targeting the excess of nutrients from urban and agricultural runoff, the extreme high and low water levels, and invasive species. You can support these efforts by learning more on their website and preventing local flooding in your area by practicing flood control behaviors like removing debris from drainage grates. Also consider using safe fertilizers and application methods to limit nutrient runoff that harms the lake’s ecosystem and water quality.