How Much Do You Know About Algal Blooms?

By: Patrick Troyer, Paulding SWCD 

Recently, some may have noticed areas along the rivers and streams may have looked a bit on the green side like you would see for St. Patrick’s Day in many towns and cities. Well, we are a bit removed from that holiday where rivers are artificially died green. So what is the issue? That green color is one culprit that we have seen dominate the agricultural headlines for the last few years which would be none other than a Harmful Algal Bloom. What causes this? Is it toxic? How could we have these blooms if we are below average on rain? What are the effects? All these questions may have crossed your mind at one point or another, so let’s get some answers.

According to the US EPA, algal blooms have become a major problem in all 50 states. In Ohio, the Toledo Water Crisis a few years back was one of the worst examples on algal blooms as quite a few were left without drinking water. These blooms have severe impacts on human health, the economy, and the aquatic environment. The US EPA notes that the harmful algal blooms can appear in a green, blue, red, and even brown color that looks like paint on the water and can be both toxic and non-toxic in which case plants and animals will use this as a food source.

According to the Michigan Sea Grant, the HABs we see in our region are made up of blue-green algae which are technically classified as a type bacteria known as cyanobacteria. The blue-green algae that cause HABs thrive on high amounts of sunlight, nutrients such as phosphorus and nitrogen, slow moving water, and shallow water.

Runoff is one way the nutrients reach the waterways, but we haven’t seen much rain recently so what’s the deal? Recent calm, dry, and hot weather in the area has lowered water levels in rivers as well as streams and created still water providing the prime environment for the algae to grow in our rivers such has been seen on the Auglaize River as well as the Maumee River.

HABs are a natural occurrence in nature but have been amplified by human activities. These algae thrive on excess nutrients that they can get from sewage discharge, dishwasher detergent, phosphorus/nitrogen lawn fertilizer, and agricultural runoff. Whether we are involved in agriculture or not we all play a part in the green color we are seeing in our rivers and lakes. The National Oceanic & Atmospheric Administration (NOAA) had predicted a large algal bloom on Lake Erie for 2019, but the size is not always an indicator of how harmful the bloom may be. A larger bloom could have a less concentrated mixture of toxins compared to a small bloom.

Some may be thinking, so what is the effect of that green water they see on the river. The blue-green algae use the oxygen in the water as part of their processes and create dead zones in the water. Without oxygen plus the water being covered by the HABs, nothing is able to survive these conditions. HABS produce toxins called mycotoxins that can cause fish kills, make the water smell, contaminate drinking water which can severely sicken both humans and animals.

What can be done to deal with the algae? There are many simple things we call can do to make sure the blue- green algae (cyanobacteria) do not have the environment in which to form. The EPA notes that simple things can be done in the home such as choosing cleaners & detergents that are phosphate free, using the right amount of detergent in the washer, picking up after our pets, and inspecting our septic systems. Washing our cars can also provide the right environment for algae as many of the soaps contain some form of phosphorus, which the blue-green algae find very pleasing. When washing the car, do so on a grassy surface as the grass will act as a natural filter before the carwash reaches the stream.

The one thing that cannot be controlled is the weather, so the shallow water and hot temperatures are factors that cannot be avoided. Regardless, if we all follow the steps described above, we at least can decrease chances of having to see the green water. It is truly the little things we can do that will make a big difference! Do your part and help us maintain a clean and safe water supply for all to enjoy!

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