Unveiling The Most Polluted Lakes In North Dakota

What are considered the most polluted lakes in North Dakota?

Let's keep in mind, that even the most polluted lakes in North Dakota would be considered some of the cleanest in other states. Despite that, I decided to investigate the subject.

I spoke with several government agencies in North Dakota before I found the right department.

Joshua Wert, with the Watershed Management Program Division of Water Quality, was kind enough to discuss North Dakota lakes with water quality issues with me.

North Dakota has a total of only 14 lakes considered "impaired" by the state.

That's pretty good, considering the state manages over 400 lakes that are open for public use. This includes both natural lakes and reservoirs.

The North Dakota landscape is also dotted with large tracts of wetlands, with densities of over 150 per square mile in some areas, according to the North Dakota Game and Fish.

What exactly makes a lake "impaired" in North Dakota?

According to the Watershed Management Program Division of Water Quality, all lakes need nutrients such as nitrogen and phosphorus, but like anything else, an excess of nutrients can cause a lake to become hypereutrophic.

These nutrients occur naturally within the lakes but can also be introduced by human activities such as farming.

A lake becomes impaired in North Dakota when it reaches hypereutrophic status. These lakes can experience cyanobacteria (blue-green algae) blooms, low transparency, and low dissolved oxygen concentrations.

These lakes can also experience fish kills and likely have excessive rough fish populations, such as carp, hullhead, and suckers.

Due to the frequent algal blooms and excessive weed growth, these lakes can also be undesirable for recreational use.

If a lake in North Dakota becomes trophic status, this is directly related to the level of nutrients (phosphorus and nitrogen) entering the lake from its watershed.

Mesotrophic lakes do not experience algal blooms, while eutrophic lakes may occasionally experience algal blooms of short duration.

These are the 14 most impaired lakes in North Dakota, according to the Watershed Management Program Division of Water Quality.