New Technology will Alert us to Algal Blooms in Lake Okeechobee
June 1st is the official beginning of hurricane season, but this year it was also the beginning of Lake Okeechobee discharges to the St. Lucie River. Above- average rainfall in May has forced the Army Corp of Engineers to open the locks and send water to the coast. This is the only option because the Herbert Hoover Dike is weak, there are people that live below the lake, and, frankly, the land between Lake Okeechobee and Florida Bay is so saturated that more water cannot be forced south through an outdated canal and levee system. Our estuaries are designed as the relief valve for Lake Okeechobee when it gets too high, and discharges will continue until we complete many infrastructure projects. To make matters worse, blue-green algae blooms have already been spotted in Lake Okeechobee this year.
Harmful Algal Blooms (HAB’s) often occur when salinities are low, nutrients are available, and warmth and sunlight are prolific. In addition to stormwater runoff in our local basins, Lake Okeechobee discharges reduce the salinity of our estuaries, and this increases algal growth. Excess nutrients are available to feed the algae from sources such as leaching septic systems, sewer failures, fertilizers, and even pet waste. Lastly, Florida is the land of sunshine and warmth, making conditions ideal for algae to multiply.
In 2016 blue green algae, otherwise known as cyanobacteria, stacked up in the St. Lucie River and portions of the Indian River Lagoon, making it unpleasant for recreation, causing trouble for businesses, and even effecting people’s health. Impacts to our health increase when cyanobacteria turn toxic, therefore understanding this organism is very important!
To gain more knowledge, NASA, Florida Atlantic University’s Harbor Branch Oceanographic Institute and the South Florida Water Management District are teaming up in June to install a SeaPRISM on a tower in Lake Okeechobee. This automated technological device is the second of its kind to be installed in a lake, with Lake Erie being the first.
PRISM stands for Portable Remote Imaging SpectroMeter. A SeaPRISM instrument has specific filters and is programmed to measure the sea and sky radiance. It is set up to take photos every 30 to 60 minutes which will be transmitted to NASA for evaluation.
What exactly, are they looking for? “Cyanobacteria,” according to Dr. Jim Sullivan at Harbor Branch, “has a specific color to it that the SeaPRISM can track.” The photos are taken at different wavelengths and the color of the water will help researchers map the algae content and the turbidity.
This information is more accurate than simple satellite imagery, and when combined with other monitoring such as water quality testing, a more complete picture will develop. This data will be publicly available as a part of NASA’s Aeronet Aerosol Robotic Network at https://aeronet.gsfc.nasa.gov
While we a long way to go before we can stop the Lake Okeechobee discharges, at least SeaPRISM can give us more notice before a large algal bloom is headed our direction.