Dry-season operations: an update on current Lake Okeechobee releases

February 12, 2021

The Army Corps has begun what they call “dry season operations,” which is essentially an approach to managing Lake Okeechobee differently in the dry, winter months when less rain is expected.

Check out this update from Captain Chris Wittman on what that means for you, what to watch for, and what Captains has to say about all of it.

Lake Okeechobee management by the numbers
  • Lake height: 15.39 ft. (2.5 ft. higher than this time last year—needs to come down)
  • Lake recession rate: 4 in. over the past month (pretty good)
  • Flows to the Caloosahatchee: increase from 1,500 to 2,000 cubic feet per second (cfs)
  • Flows to the St. Lucie: maintained at 0 cfs
  • Flows south: increased to 200 cfs as some capacity has become available
Flows increase to the Caloosahatchee—the takeaways

Under their dry-season operations, the Corps is being aggressive to get the lake levels down now to prevent high-volume discharges during the summer when harmful algal blooms (HABs) are more likely. The intent of the Corps increasing flows to 2,000 cfs now is to get the level of the lake down leading up to the wet season and to provide the Caloosahatchee with minimum beneficial flows during the dry season.

During the dry season, when the Caloosahatchee is not receiving much rainfall, the upper estuary can benefit from minimum flows to balance salinity levels. The sweet spot in the dry season is around 1,000-2,000 cfs, so current releases are around the upper limit. 1,000-2,000 cfs in the dry season is much different and more manageable than those same flows during the wet season, when the system is also dealing with rainfall and local basin runoff, which compound the amount of freshwater in the system.

These minimum flows to the Caloosahatchee may be necessary to balance salinities in the dry season, but they shouldn’t be used as a “tool” for lowering the lake and creating capacity. In the current situation, they are being used as a tool, but they’re really more of a band-aid that the Corps is being forced to implement because there is a lack of capacity south of the lake right now.

Ideally, the primary strategy to lowering the lake in the dry season would be through sending more water south to the Everglades and Florida Bay—something that Everglades restoration projects like the EAA Reservoir will help to facilitate.

Why can’t they send more water south right now?

Due to record rainfall last year, many components of the current system—like the water conservation areas (WCAs)—have been at capacity and inundated with water. Thankfully, some capacity has become available, but 200 cfs is a very small amount. The Corps does anticipate being able to increase flows south as more capacity becomes available throughout the dry season.

Why aren’t they releasing any flows to the St. Lucie?
  1. That canal is much smaller—it simply doesn’t move as much water.
  2. Although the Caloosahatchee needs some minimum flows to maintain salinity balances during the dry season, the St. Lucie absolutely does not.
What about the threat of red tide?

Although there is still some red tide present out there, reports have shown good signs ecologically in the Caloosahatchee and along the Gulf Coast, and releases of 2,000 cfs now allow for enough mixing in the river to prevent any sort of large plumes pushing out into the gulf. Those large plumes—which are more likely to occur this summer if lake levels aren’t lowered now—pose a much greater threat of seriously intensifying red tide.

Bottom line, if we have to take releases, it’s better to take them now, rather than during the wet season. Ultimately however, the end goal—and what we’re all fighting for—is to send that water south to the Everglades and Florida Bay, where it’s desperately needed to balance salinity levels during the dry season.