The Florida Department of Environmental Protection (FDEP) and South Florida Water Management District (SFWMD)  monitor water quality on Lake Okeechobee as summer algal blooms continue on the big lake.

According to FDEP, cyanobacteria (commonly called blue-green algae) are part of the natural ecosystem and found in lakes, streams, canals and other waterways throughout the world. They are part of the food chain and produce oxygen. Most of the year, these microscopic organisms are invisible to the human eye. Under certain conditions -- hot weather, little water movement and available nitrogen and phosphorus in the water -- they can reproduce rapidly into a visible "bloom." 

Of the 28 species of cyanobacteria documented by the U.S. Geological Survey in the Lake Okeechobee Waterway, about 25% are capbable of producing toxins. However, toxins are not always produced by these cyanobacteria.

The World Health Organization (WHO) and Environmental Protection Agencay (EPA) consider microcystin levels below 1.0 parts per billion (ppb) to be safe for drinking water and levels below 8.0 ppb to be safe for recreational contact (swimming).

July 22-24, South Florida Water Management District staff collected eight HAB response samples, six routine monitoring samples at structures and 25 Lake Okeechobee routine monitoring samples. 

Most samples had no detectable toxins.

Three samples had toxin levels above 8.0 ppb. These sites are marked L004, L008 and  LZ40 on the map.

Dominant algal taxa and cyanotoxin results follow each waterbody name.

• Lake Okeechobee - S135LOCKDS: No dominant algal taxon; no cyanotoxins detected.
• L-47 Canal - S135LOCKUS: No dominant algal taxon; no cyanotoxins detected.
• L8 Canal - CULV10A: Microcystis aeruginosa; no cyanotoxins detected.
• Lake Okeechobee - S271: No dominant algal taxon; no cyanotoxins detected.
• Lake Okeechobee - S351: No dominant algal taxon; no cyanotoxins detected.
• Lake Okeechobee - S352: No dominant algal taxon; no cyanotoxins detected.

• Lake Okeechobee - S354: Microcystis aeruginosa; trace level (0.67 ppb) microcystins detected.
• Lake Okeechobee - Pahokee Marina: No dominant algal taxon; no cyanotoxins detected.
• C43 canal (Caloosahatchee River) - S77 (Julian Keen Jr. Lock, upstream): No dominant algal taxon; no cyanotoxins detected.
• C43 canal - S78 (Ortona Lock, upstream): No dominant algal taxon; no cyanotoxins detected.
• C43 canal - S79 (W.P. Franklin Lock, upstream): Microcystis aeruginosa; no cyanotoxins detected.
• C44 canal (St. Lucie Canal) - C44S80: No dominant algal taxon; no cyanotoxins detected.
• Lake Okeechobee - S308C (lakeside): Microcystis aeruginosa; trace level (0.38 ppb) microcystins detected.
• C44 canal - S308C (St. Lucie Lock): No dominant algal taxon; no cyanotoxins detected.
• KISSR0.0: Raphidiopsis raciborskii; no cyanotoxins detected.
• LZ2: No dominant algal taxon; no cyanotoxins detected.
• NES191: No dominant algal taxon; no cyanotoxins detected.
• L001: No dominant algal taxon; no cyanotoxins detected.
• NES135: No dominant algal taxon; no cyanotoxins detected.
• NCENTER: Microcystis aeruginosa; no cyanotoxins detected.
• EASTSHORE: Microcystis aeruginosa; trace level (0.54 ppb) microcystins detected.
• L004: Microcystis aeruginosa; 22 ppb microcystins detected.
• L008: Microcystis aeruginosa; 3.4 ppb microcystins detected.
• L005: Microcystis aeruginosa and Dolichospermum sp. co-dominant; no cyanotoxins detected.
• POLESOUT3: Microcystis aeruginosa; trace level (0.28 ppb) microcystins detected.
• POLESOUT2: Microcystis aeruginosa and Dolichospermum sp. co-dominant; no cyanotoxins detected.
• CLV10A: Microcystis aeruginosa; 1.2 ppb microcystins detected.
• LZ40: Microcystis aeruginosa; 8.8 ppb microcystins detected.
• L006: Microcystis aeruginosa; 1.3 ppb microcystins detected.
• PALMOUT3: Microcystis aeruginosa; 3.1 ppb microcystins detected.
• PALMOUT2: Microcystis aeruginosa and Pseudanabaena mucicola co-dominant; 3.0 ppb microcystins detected.
• PALMOUT1: Microcystis aeruginosa; 1.3 ppb microcystins detected.
• PALMOUT: Microcystis aeruginosa; no cyanotoxins detected.
• LZ30: Microcystis aeruginosa; no cyanotoxins detected.
• POLE3S: No dominant algal taxon; no cyanotoxins detected.
• RITTAE2: Microcystis aeruginosa; no cyanotoxins detected.
• LZ25A: Microcystis aeruginosa and Pseudanabaena mucicola co-dominant; no cyanotoxins detected.
• L007: No dominant algal taxon; no cyanotoxins detected.
• PELBAY3: No dominant algal taxon; no cyanotoxins detected.

The Florida Department of Health advises the public to avoid areas with visible algal blooms and to keep children and pets out of the water if algae is visible. If you come into contact with blue-green algae, wash off with soap and water, especially if your skin is easily irritated. 

 According to FDOH, fish tested from water with blue-green algae show that cyanotoxins do not significantly accumulate in the edible parts—muscle or filet—of fish, but can in other organs. Prior to consuming, rinse fish fillets with tap or bottled water, throw out the guts, and cook the fish well. Do not eat shellfish in waters with blue-green algae blooms.