Satellite imagery shows algae potential in lake


LAKE OKEECHOBEE — The intense summer heat has brought with it algal blooms on Lake Okeechobee. Lake area fishermen have noted this is a common occurrence in the summer.

As of June 29, the lake level was at 12.36 feet, just slightly higher than the previous week’s level of 12.33 feet.

No water from the lake has been released to the St. Lucie River since March 2019. Water is only released west into the Caloosahatchee River if it is needed to prevent saltwater intrusion. Average flow at the Moore Haven Lock for the seven-day period was 216 cfs. Average flow at the Franklin Lock was 877 cfs. Under the current operating plan, when there is sufficient local basin runoff to maintain freshwater flow through the Franklin Lock at the desired levels, no water is released from the lake.

The basin runoff into the C-44 Canal continues to backflow into Lake Okeechobee. For the seven-day period ending June 29, the average flow was 269 cubic feet per second (cfs) or about 174 million gallons a day. Since the start of the rainy season, more than 19 billion gallons of water have back flowed from the C-44 into the lake, according to the U.S. Army Corps of Engineers.

According to the Department of Environmental Protection:
• On June 23, SFWMD staff collected samples at 15 sites in the northern portion of Lake Okeechobee. Five of the sites were dominant for Microcystis aeruginosa. Three of the sites were co-dominant with Microcystis aeruginosa and Cylindrospermopsis raciborskii. Other samples were mixed with no dominant species. While most samples had no toxins or very low levels of toxins, one sample taken off shore of the Port Mayaca Lock had a toxin level of 800 micrograms per liter — 100 times the level considered safe for human recreational contact. That area has been the source of some controversy this year because billions of gallons of nutrient-rich water have back flowed into Lake Okeechobee from the C-44 basin this year.
• On June 24, SFWMD collected samples at 12 more sites in the lake.
• On June 24, an algae bloom was sampled in the North Fork of the St. Lucie River in St. Lucie County. Dominant taxon was Microcystis aeruginosa. No toxins were detected.
• On June 25, an algae bloom was sampled at the Davis Boat Ramp on Caloosahatchee River in Lee County. Co-dominant taxa were: Dolichospermum circinale and Microcystis aeruginosa. No toxins were detected.
• On June 26, an algal bloom was sampled on Gator Lake in Lee County. Dominant taxon was Microcystis aeruginosa.