MATTOON -- Blue-green algae blooms are continuing to cause strong odors at Lake Paradise but they do not appear to be getting worse, city officials reported.
Public Works Director Dean Barber said the city is waiting for a consistent set of water test results that will indicate whether or not the blooms are starting to dissipate. In the meantime, he said, the blooms do not appear to be getting worse at Lake Paradise southwest of Mattoon.
Due to the high levels of blooms in Lake Paradise, the city has switched to drawing water from Lake Mattoon to the south as a precaution. The 210-acre Lake Paradise is the city's primary water source and 1,050-acre Lake Mattoon is the secondary source. The city's water system is designed to switch between the two lakes as needed. The Little Wabash River flows into both lakes.
Barber said the city has been regularly testing the water at Lake Mattoon and has not found blue-green algae blooms to be an issue there.
The Illinois Environmental Protection Agency issued a notice earlier this year about blue-green algae bloom levels being high during the summer in several lakes and rivers. In addition, Barber said that the Minnesota Pollution Control Agency has issued an informative report about blue-green algae and that the blooms are at high levels throughout much of Florida.
"People all the way from Minnesota to Florida are going through similar things," Barber said.
The Minnesota Pollution Control Agency reported that when temperatures climb and the summer sun beats down, conditions are ripe for lakes to produce algae blooms, some of which can be harmful to pets and humans.
"Blue-green algae are not algae at all, but types of bacteria called cyanobacteria that are normally present in many lakes. This type of bacteria thrives in warm, nutrient rich water. When conditions are right, the bacteria can grow quickly, forming blooms," the Minnesota report stated.
According to this report, the blooms are often described as looking like pea soup or spilled green paint. However, blooms are not always large and dense, and can sometimes cover small portions of the lake with little visible algae present. Blooms can also produce a swampy odor when the cells break down.
The Minnesota Pollution Control Agency reported that blue-green algal blooms produce toxins from bacteria that can make humans and animals sick. People can become sick if they swallow or have skin contact with water that has harmful algae, of if they breathe in airborne water droplets. Symptoms can include vomiting, diarrhea, rash, eye irritation, cough, sore through, and headache.
"There is no way to tell if a blue-green algal bloom is toxic just by looking at it. Adults, children and animals should avoid contact with water with blue-green algae. Toxins can persist in the water after a bloom. Watch for signs of recent blooms, such as green scum on the shoreline. When in doubt, stay out. If you or your pet go into water where there may be a bloom, wash off with fresh water immediately afterwards," the report states.
The Minnesota Pollution Control Agency reported that blue-green algae cannot be eliminated from a lake because they are an inherent part of the overall algal community. The agency reported that the intensity and frequency of the blooms can be controlled by reducing the amount of phosphorus and nitrogen nutrients that run off from surrounding land and feed the algae.