Potentially toxic blue-green algae found July 18 in Lake Washington is a direct concern to beachside Melbourne Utilities customers south of Pineda Causeway as the lake serves as the city utility’s primary drinking water supply.
A volunteer with the Jacksonville-based St. Johns Riverkeeper organization discovered the bloom and was sickened in the process of taking water samples.
Yet state and local officials all stress that, after treatment, the water is safe to drink.
Melbourne Utilities and officials from two state agencies tasked with water quality say recent tests show only low levels of toxins which are being neutralized by additional treatment methods, some of which have caused customer complaints of odors.
Florida Department of Environmental Protection and St. Johns River Water Management District staff reported that no microcystins, cylindrospermopsins or anatoxin-a toxins were detected, but low levels (0.06 to 0.18 parts per billion) of saxitoxins were present in the four St. Johns River Water Management District samples.
Riverkeeper volunteer Bill Zoby of the Headwaters Advisory Council became somewhat ill while taking water samples with blue-green algae from the lake, said Lisa Rinaman of Jacksonville, the head of St. Johns Riverkeeper. Zoby collects monthly samples in Lake Washington and Blue Cypress Lake.
While several factors in poor water quality such as pesticides and fertilizers can result in various algae blooms, Rinaman believes the likely direct cause of the Lake Washington blue-green algae bloom to be the trucking of South Florida’s sewage sludge (also known as “biosolids”) to Indian River, Brevard and Osceola counties.
In 2007, legislation was enacted to prohibit land application of sewage sludge from adding to nutrient pollution in South Florida waterways. Since then, more than 89,000 tons of South Florida’s sewage sludge have been disposed of within the Upper Basin of the St. Johns River, including Lake Washington, fueling harmful algal blooms, according to information on St. Johns Riverkeeper website.
Lake Washington currently shows some of the highest phosphorous levels on the entire St. Johns River, which Rinaman calls “strong evidence” it is due to the trucking of South Florida’s sewage sludge. Phosphorous is known to fuel toxic blue green algae outbreaks, she said. “Sadly, we are seeing algae outbreaks throughout Florida, but very few cities get there drinking water from surface waters,’’ she said.
Related action items proposed by Riverkeeper to address the crisis include: the state must stop the trucking of sewage sludge to the headwaters of the St. Johns; Florida needs a more protective strategy of dealing with human waste, including new technologies to deal with sewage sludge and phase out septic tanks; and the state needs to enact protective policies to keep agriculture and urban fertilizer out of our waterways.
The non-profit St. Johns Riverkeeper is a member of the Waterkeeper Alliance, considered one of the world’s fastest growing environmental movement with over 270 Waterkeeper Organizations protecting rivers, lakes and coastal waterways on 6 continents.
Anyone who sees a blue-green algae bloom should notify the FDEP Hotline at the link https://floridadep.gov/dear/algal-bloom/content/algal-bloom-contacts.