After two decades of work, water storage and treatment facilities east, west and south of Lake Okeechobee are ready to use … just waiting on Mother Nature.

So far this wet season, Lake Okeechobee has stayed at around or just below 11 feet above sea level. So far, most rainfall has been offset by evapotranspiration – the combination of evaporation and plant transpiration.

C-43 reservoir

West of Lake Okeechobee, the C-43 reservoir, south of the Caloosahatchee River west of LaBelle, was completed last summer. Testing could have started then, but was delayed by lack of water. The primary purpose of this reservoir is to store excess freshwater from the Caloosahatchee River in the wet season and release that water, as needed, in the dry season. While in the reservoir, the water will be treated to reduce the phosphorus content. Most of the flow to the Caloosahatchee estuaries in the wet season is local basin runoff. Due to flood control measures, that watershed drains much faster than nature designed.

Too much or too little freshwater flow disrupts the salinity levels in the estuaries.  

During the dry season, for decades the river has depended on freshwater flow from Lake Okeechobee to prevent saltwater intrusion in the river. In drought years, the river suffers when flow from the lake lessens. The 10,000-acre reservoir, which can hold up to 170,000 acre-feet of water, was designed to alleviate that problem.

C-44 reservoir

East of Lake Okeechobee, the C-44 reservoir was designed to hold excess basin runoff from that basin, protecting the St. Lucie River estuary from damaging freshwater flows. The 3,400-acre reservoir is operational and approved to hold water up to 10 feet deep. Water from the reservoir is treated in a 6,300-acre stormwater treatment area before being released back into the C-44 canal (St. Lucie Canal). As of July 17, the water level was about 3.6 feet. The reservoir was designed to hold water up to 15 feet deep, but after initial testing was only approved to 10 feet. Additional work is underway to add the capacity up to 15 feet. The reservoir and STA have been operational since 2021.

A-2 STA

South of the Lake, the A-2 STA was completed last year and is also waiting on rainfall. This stormwater treatment area can accept water directly from Lake Okeechobee or from the Everglades Agricultural Area (EAA) reservoir. (The EAA reservoir is still under construction.) The 6,500-acre A-2 STA is designed to hold water about 18 inches to 2 feet deep, maximizing the water treatment provided by vegetation, which will remove phosphorus and nitrogen from the water naturally. The EAA STAs, which were designed both for flood control and to treat runoff from the EAA, hold water up to 4 feet deep. The shallower A-2 STA is better suited to treat water directly from Lake Okeechobee, which is often higher in phosphorus than the runoff from the EAA. The STA was designed to treat up to 360,000-acre feet of water per year. Clean water will be released south, under the Tamiami Trail, to Everglades National Park and Florida Bay.

Tamiami Trail

Since the 1920s, the biggest roadblock to moving water south has been the Tamiami Trail, which bisects the Southern Everglades from Tampa to Miami. For decades, the road acted as a dam, backing water up on the north side, flooding the water management areas and drowning the tree islands. Culverts under the road were not sufficient for the flow, and some water control structures were closed 9 months of the year to protect the nesting grounds of a subpopulation of the endangered Cape Sable Seaside Sparrow. Work is underway to raise more portions of the road to allow water levels north and south of the trail to equalize. According to information shared at the July meeting of the South Florida Water Management District Governing Board, that project should be completed later this year.