Lake Okeechobee is in good shape to handle what Mother Nature may send, according to U.S. Army Corps of Engineers (USACE) Hydraulic Engineer Savannah Lacy, who spoke to reporters in a media conference call on Aug. 2.

Lacy said USACE is actively tracking potential tropical storm Debby. “The forecast is uncertain,” she added. Currently, the forecast calls for about 5 inches of rain in the Kissimmee River Basin and up to 7 inches of rain over Lake Okeechobee and the water conservation areas (WCAs).

“With the current forecast that we have, we feel like we are in a really good place to accept this rainfall,” said Lacy. She said they do not believe the expected rainfall will trigger any Lake O releases.

She stressed the forecast can change.

In anticipation of the storm, USACE is opening water control structures south of the lake to try to move more water under the Tamiami Trail to Everglades National Park and Florida Bay before the storm. On Thursday, flow under the road was about 2,200 cubic feet per second (cfs).

She said the S-12s, 333s and 343s (water control structures) are already open and maximized but the S-10s and 11s have been closed. “We’re opening those today and allowing it to flow to the park,” she explained. “We’re targeting 2,000 cfs at S-10 and 2,000 cfs at S-11.

“We should see an increase of the flows across the trail,” she said.

Lacy said the WCAs have been above schedule since June due to direct rainfall south of Lake O.

“With WCAs already above schedule it’s unlikely we’ll be able to send any water south out of the lake,” she explained.

Lake Okeechobee’s level has had almost no change for the last month. Lacy said inflows are around 4,100 cfs. Outflows are around 100 cfs. Most of the water leaving the lake is via evapotranspiration – a combination of evaporation and plant transpiration.

 No lake water is being released to the St. Lucie Canal (C-44 canal). Lacy said the C-44 reservoir is currently 6.75 feet deep. The reservoir was originally designed to hold water up to 15 feet deep, but is currently only rated to store water 10 feet deep. Lacy said there is sufficient capacity in the reservoir to accept runoff from the C-44 basin if a storm hits.

 For the seven-day period ending Aug. 1, flow at the Julian Keen Jr. Lock (S-77) at Moore Haven averaged 348 cfs. Flow at the W.P. Franklin Lock (S-79) averaged 2,687 cfs. The target for the Caloosahatchee is 2,000 cfs, measured at the W.P. Franklin Lock, which is more than 43 miles from Moore Haven. If local basin runoff meets or exceeds that target, no lake water is released.

Heavy rainfall south of Lake O has meant no lake water has been needed for irrigation of crops or water supply for the urban areas. The direct rainfall has also meant the stormwater treatment areas (STAs) and water conservation areas (WCAs) have no capacity to accept lake water.

According to the NOAA satellite imagery, the algal bloom potential on Lake Okeechobee dropped considerably this week from more than 400 square miles to around 220 square miles, but moderate bloom potential remains along the northwest shoreline.

Lacy said USACE staff has not seen any visible blooms in or near the Lake Okeechobee Waterway structures or in the water control structures on the lake.