What is Eutrophication?


Eutrophication is the release of excess nutrients into bodies of water. This can be a natural process that develops aquatic ecosystems, but it can also be an indication of nutrient imbalances as a result of pollution. 

Want a hot take? While the cycle of nutrients is a natural process, human-driven eutrophication accelerates this process so much that what was once great for a water system is now toxic. 

Sum it up? You got it. Human Activity > Pollution > Eutrophication > Harmful Algal Blooms > Oxygen Deficit > Dead Zone

Is Eutrophication “good”?

Eutrophication is bad news. Excess nutrients may sound like a good thing (who doesn’t want extra nutrients, right?), but eutrophication has a sinister impact — it can cause algal blooms, which deplete the water of oxygen and slowly kill aquatic ecosystems. Plants need nutrients to survive like any other living organism, but too much of a good thing can be a problem. While nutrients like nitrogen and phosphorus occur naturally, the overabundance of these nutrients in water systems mainly stems from human activities. Algae feed on these nutrients, causing them to grow and spread rapidly, oftentimes turning the water green. These harmful algal blooms (aka HABs) block sunlight, have an awful smell, and can even release toxins into the water system. This algal growth jumpstarts another process whereby bacteria breaks down the algae when they die. When bacteria breaks down algae it requires a lot of oxygen that is dissolved in the water. Believe it or not, fish actually need oxygen to survive too, and when bacteria is decomposing the dead algae, it requires a lot of oxygen and can deplete a water system so much that there is not enough oxygen to sustain life. Areas in the water that experience these “hypoxic” conditions are called dead zones because no life can exist under the water in that area. 

What kind of products cause Eutrophication?

Unfortunately, it’s tough to pinpoint exactly which products lead to eutrophication because human activities and sources like fertilizers, wastewater/greywater, automobile exhaust, and animal waste all contribute to the overabundance of these nutrients in water systems.

Are there certifications I should look out for?

There are no certifications specific to eutrophication, but there are steps you can take at home to help prevent it.  A great prevention measure is recycling your greywater. If you or a commercial business want to set up a greywater system you would have to obtain certain permits and certifications. One of them is the NSF/ANSI 350, which establishes clear and realistic guidelines for testing of greywater and wastewater reuse treatment systems.

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