Reader asks: Why isn't the lake rising?
- Katrina Elsken Lake Okeechobee News
- 5 days ago
- 2 min read
Florida’s rainy season has returned, as evidenced by frequent heavy afternoon showers.
A Lake Okeechobee News reader asked: Why isn’t the lake rising?
The Big O, the second largest freshwater lake within the confines of the continental United States, has been around 12 feet above sea level (10.74 feet NAVD88) for most of the summer.
Recent thunderstorms, often accompanied by lightning and high winds, have soaked much of the watershed around Lake O.
So where is that water going?
South Florida Water Management District (SFWMD) data shows much of the water that comes down from the skies goes right back up via evapotranspiration – the combination of evaporation and plant transpiration.
Data from the seven-day period July 28-Aug. 3 shows the lake received 11,630 acre feet of water in direct rainfall and 21,010 acre feet in surface inflows. During that same period, the lake lost 41,890 acre feet of water to evapotranspiration.
According to information shared at the July meeting of the SFWMD Governing Board, as the lake level slowly rises, water is also soaking into the soils in the marshy areas around the lake’s edge. SFWMD Applied Science Bureau Chief said these areas are rehydrating. Once the soil is rehydrated, as water comes in, the lake will rise, she explained. As the lake slowly rises, more soil around the edges is rehydrated.
At 15.5 feet, Lake Okeechobee’s marshes are completely inundated. If the lake level rises above 15.5 feet, water stacks up against the side of the Herbert Hoover Dike, an earthen berm surrounding the big lake for flood control.
A slow ascension of the lake level is just what many lake scientists, environmentalists and anglers have hoped for.
Due to damage from hurricanes and high water levels, Lake O lost most – if not all – of the submerged aquatic vegetation (SAV) that filters the water and provides critical habitat for young fish. At the end of the 2024 wet season, SFWMD officials reported the lake had less than 4,000 acres of SAV. Scott Martin, of Anglers for Lake Okeechobee, reported he found “zero” SAV on the big lake.