Sediment: a natural water pollutant

  • Published
  • By Nicole Johnston, 460th Civil Engineer Squadron Stormwater Project Coordinator
When you see muddy tire tracks on the street, what is the first thing you think? Maybe you think of your own 4-wheeler, or maybe it reminds you of how muddy it's been lately from the melting snow and rain. I'm sure the last thing you might think is that sediment is a pollutant.

Sediment is the loose sand, silt, clay and other soil particles that settle at the bottom of a body of water and pollutes our streams, rivers and oceans.

You might be asking yourself, how can sediment be a pollutant? Isn't sediment found in nature?

Sediment becomes a pollutant when erosion occurs. In fact, the United States Environmental Protection Agency lists sediment as the most common pollutant in rivers, streams, lakes and reservoirs. This acceleration can cause many problems.

One of the biggest causes of pollutants entering our streams, rivers and wetlands occur through storm sewer drains or drainage ditches. When pollutants enter a storm sewer drain or drainage ditch, they will eventually make their way into streams, rivers and oceans. Stormwater runoff is not treated before being discharged into drainage collection systems.

Besides sediment polluting our water, it also increases the potential for flooding our roads and homes when it clogs storm drains, as well as harming our ecosystem and food chain.

Sediment clouds water which prevents animals from seeing food, while at the same time clogs fish gills making it harder for them to breathe. Murky water also prevents natural vegetation from growing, which in turn destroys the habitat of small stream organisms, ultimately declining the fish population.

Sediment buildup in streams, lakes and oceans is essentially impossible to control. However, below are a few things we can do to help slow the process.

The most common cause of sediment pollution is from construction activities. Mud or dirt that ends up on the pavement needs to be cleaned up as soon as possible by both scraping it with shovels and sweeping by hand, or by mechanical sweepers. Using perimeter control Best Management Practices on a construction site helps control sediment from leaving the site.  A Vehicle Tracking Control pad also minimizes the amount of sediment leaving a site by removing it from vehicle tires. 

Off-road vehicles are also a big culprit of expedited erosion.  It becomes difficult for water to seep into the soil once it is compacted and it is challenging for re-vegetation to occur. Off-road vehicles also track sediment onto paved roads. Cleaning up that muddy mess has been expensive for the Buckley Air Force Base Operations Group recently. By not driving or parking off-road, you can prevent multiple problems.

The above examples are just a few things we can do to keep sediment from polluting our water. Keeping our water clean is everyone's responsibility. By being aware of the problem, we can be part of the solution.