MIAMI – This dry season is one of the driest on record.

At the May 8 meeting of the South Florida Water Management District (SFWMD), Chief District Engineer John Mitnik said the month of April brought just 16% of normal rainfall, “the lowest on record for the month of April.”

Since October, the dry season has seen less than half of normal dry season rainfall.

“Hopefully wet season will start shortly,” he added.

The Upper Chain of Lakes are down to the summer pools. Lake Kissimmee is well below regulation schedule.

“It’s drier than it was last month,” said SFWMD Bureau Chief of Applied Sciences Cassandra Armstrong.

“We have very little water on the floodplain,” she continued. “But this is not unusual for the Kissimmee River.”

She said the river still has good oxygen levels for fish.

Mitnik said the northern portion of the district received a lot less rainfall over the last two years than previous years.

There is a possibility the lake will go into the water shortage management band if the wet season does not start by June, Mitnik added.

“Right now, all indicators are that we will achieve success in recovery operations,” said Mitnik. The goal is for the lake to be below 12 feet for 90 days or below 11 feet for 60 days.

“We’ll try to manage the rise and hope that it doesn’t come as one big deluge,” he said.

Armstrong said more than half of the water leaving the lake in April was via evapotranspiration (a combination of plant transpiration and evaporation).

“The intent here is to increase the ability of the SAV to regrow and produce the biomass that it can survive when the water levels go back up,” she explained.

“We are having a lot of bird usage of the lake,” she said. Mud flats on the south end of the lake have seen a lot of ducks. An annual survey of wading birds shows that foraging for wading birds is higher than last year.

“Precipitation has been quite low,” she said. “We’ve only had four rain events on the lake over the last month. The largest was 0.2 inches.”

The water quality on the lake has improved over the past couple of months, she said. In the nearshore, the dissolved inorganic nitrogen levels have dropped. She said algae are consuming the nitrogen, but they are not forming visible blooms. Cyanobacteria, commonly called blue-green algae – are part of the lake’s natural ecosystem.  About 25% of the 28 species of cyanobacteria documented in the Lake Okeechobee Waterway (the Caloosahatchee River, Lake Okeechobee, the St. Lucie Canal and the St. Lucie River) are capable of producing toxins, but do not always do so. Research has connected toxin production with high levels of nitrogen in the water.

“We are not anticipating a bloom in the near future,” Armstrong said. No toxins were detected in recent water samples.

The turbidity in the water nearshore has declined, which will make it easier for SAV to grow, she said.  

Lake releases to the St. Lucie stopped on March 29. Salinity levels are rising in the St. Lucie Estuary but are still within the optimal range for oysters there, Armstrong said.

Lake releases to the Caloosahatchee River declined in April and as a result salinity levels have increased, she continued. “However, Cape Coral is still in the optimum range for adult oysters,” she said.

In the stormwater treatment areas (STAs) south of the lake, most are at their target stage, said Armstrong.