What is that blue-green algae, is it really dangerous, and can it be treated?
One of New Hampshire’s distinguishing features is our nearly 1,000 lakes and ponds that are larger than 10 acres. We host an additional 3,000 small ponds scattered throughout the state. Lucky for us, most of that water is relatively healthy. However, if you live in the water during the summer months, you may well have been warned off one of your favorite swimming beaches by cyanobacteria warnings. Here at Secondwind, we always love digging into gross stuff, even when it’s not something we really treat. These blooms of bacteria qualify.
What Is Cyanobacteria?
According to the New Hampshire Department of Environmental Services Environmental Fact Sheet on Cyanobacteria, “Cyanobacteria are bacteria that photosynthesize. Many species of cyanobacteria grow in colonies to form surface water “blooms.” Blooms are usually blue-green in color and consist of thousands of individual cells.” They are eaten by many ‘grazers’ within the ecological system of the lake. When the water temperature rises, the bacteria, which spends most of the winter at the bottom of the lake or pond, rises to the surface. As light reaches it, it forms a scum or surface on the top of the water. They usually start showing up in mid-to-late summer. As of this writing, in NH we’ve already had a few warnings popping up throughout the state.
Are Blooms of Cyanobacteria Dangerous?
A few types of Cyanobacteria, at certain levels, are toxic to humans, pets, and livestock. The EPA lists health advisories for only two types of cyanobacteria. You can read extensive information from the EPA about cyanobacteria here.
Most humans feel the impact of this bacteria after drinking it, however, swimming in it has also caused problems for many people. When ingested, cyanobacteria can cause people to have symptoms with their nervous system and brain. It also impacts main organs and the digestive system (eating contaminated fish or shellfish can also affect the digestive system). Contact while swimming can irritate the skin, throat, and eyes as well as cause a fever.
More and more we hear about the danger to pets, mostly our canine companions. Dr. Justine A. Lee, DVM, writing for the Pet Health Network advises avoiding any lake or pond that has blue-green algae, or cyanobacteria in it. Dogs can go into deep respiratory distress as well as liver failure when ingesting water that has this toxic substance in it.
A Vigilant Watchdog
The NH Department of Environmental Services closely monitors NH’s lakes and ponds for these blue-green algal blooms to help keep our residents and visitors safe. They have a whole process that you can learn about here. But you can always just check their website and handy beach advisory map, to look for warnings. Also know that they post very clearly at any beaches that are not currently safe.
Does Secondwind Treat Cyanobacteria?
The State of NH does not recommend drinking lake water, treated or otherwise. Treatment technologies do exist that can handle the contaminants that might be found in lake water. We do have municipalities in NH that use lake water for their main source of water and they work very diligently to maintain quality during the warm summer months. We also have residential customers who pull lake water for use in their summer camp.
In all these cases a careful consideration of maintenance requirements and risk must be done before deciding that this is a good approach.
Stay Informed – Have Fun
There is really no reason to fear plunging into our beautiful waters this summer. Just pay attention to the information provided by local and state authorities, keep your eyes out for that blue-green yuck, and hold your nose and jump in! The water is juuuuuuusst fine.
