Lake Okeechobee is just outside the CHNEP area; however, its management and water quality have a direct and significant impact on the ecological health of the Caloosahatchee River, its estuary, and watershed. The man-made dike surrounding the lake provides necessary flood protection to area residents, and the Lake's water levels are controlled by a series of water control structures to its west, east and south. However, these artificial elements and the Lake's operations have caused unintended negative consequences for the ecological health of the Kissimmee River basin and the Everglades, as well as for the St. Lucie and Caloosahatchee Rivers and their estuaries. The lake is polluted with excessive nutrients and pesticides and as a result, experiences periodic cyanobacteria algae blooms. High water levels in the lake cause concern that the dike may breach, endangering public health and safety. Additionally, high Lake levels for sustained periods can cause the Lake's submerged aquatic vegetation to die off, resulting in decreased aquatic habitat and poorer water quality.
The Caloosahatchee River and its estuary require regular, adequate and appropriate levels of freshwater flow from the Lake to maintain proper salinity in its tidal reach for maintaining conditions for its aquatic life. Therefore, proper management of Lake discharges is imperative for maintaining a ecological health Caloosahatchee River and Estuary. Lake Management and controlling the timing and amount of discharges from the Lake is a delicate balancing act that must consider public safety, the health of the lake, and the health of the estuaries. Too much freshwater flow lowers salinity excessively in the estuaries and overwhelms them with pollutants from the lake. Too little flow, and the estuaries suffer harm from low water levels and high salinity. Detailed information about the release schedule is documented in the Lake Okeechobee System Operating Manual (LOSOM).
Lake Okeechobee & Caloosahatchee Estuary Tracker
The graphs below show recent elevation levels1 of Lake Okeechobee, and the corresponding rate of discharge (flow)2 of water into the Caloosahatchee River. "Lake Management Bands" comprise the background of the graphs; these bands are defined in the LOSOM. The health minimum and maximum define the optimum ranges for lake level and river flow.
1 As measured by SFWMD station "L OKEE", which is a composite "pseudo-station" that reports the daily mean of eight elevation gages operated by the Army Corps of Engineers (ACOE).
2 Mean daily flow of water from Lake Okeechobee into the Caloosahatchee River, as measured at the WP Franklin Lock, in cubic feet per second (cfs).
* The Lake Okeechobee Lake Stage Performance Measure indicates that an elevation of 11.5-15.5 feet supports healthy lake ecology.
** The Northern Estuaries Salinity Envelope Performance Measure indicates 750-2100 cubic feet per second supports healthy river and estuary ecology in the Caloosahatchee River. [Note: daily point is 14-day moving average of previous 14 days]
- Lake Stage (ft., NGVD)
- Lake Okeechobeee Ecological Health Min/Max*
Lake Management Bands
- High - Lake deep; flood risk. Harmfully high discharges to estuaries likely, and lake ecology at great risk.
- Intermediate - Lake deep; flood risk. Potential for harmfully high discharges to estuaries, and lake ecology at potential risk.
- Low - Lake generally in range for public safety, water supply & environmental needs. Some potential for harmfully high discharges.
- Base Flow - Lake generally in range for public safety, water supply. Environmental needs may not be met and releases needed for estuary health may or may not be provided.
- Beneficial Use - Lake generally in range for public safety, but water supply and environmental needs at risk. Releases needed for estuary health may or may not be provided.
- Flow Rate (cfs)
- Estuary Ecological Health Min/Max**
- Lake Okeechobee Webpage (SFWMD)
- Current Lake Okeechobee Water Level (ACOE)
- Lake Okeechobee System Operating Manual (LOSOM) (ACOE)
- LOSOM Fact Sheet. Nov 2019 (ACOE)
- Lake Okeechobee and Vicinity Report (ACOE)
- History of Flushing Okeechobee Dates Back to 1800s (News-Press)
- Managing High Water Levels in Florida's Largest Lake: Lake Okeechobee (UF/IFAS)