Our Pollution

Like most urban areas, the biggest source of pollution to our creeks is not from one point source (like a pipe pouring waste into the creeks), but rather nonpoint source pollution. The Environmental Protection Agency says that unlike pollution from industrial and sewage treatment plants, nonpoint source (NPS) pollution comes from many diffuse sources. NPS pollution is caused by rainfall or snowmelt moving over and through the ground. As the runoff moves, it picks up and carries away natural and human-made pollutants, finally depositing them into lakes, rivers, wetlands, coastal waters and ground waters. In other words, when it rains our city takes a bath.

Part of what makes St. Louis such a great city is that it's an old city. However, one of the downsides is the out-dated technology of our sewer system. A combined sewer is a type of sewer system that collects sanitary sewage and stormwater runoff in a single pipe system. Combined sewers can cause serious water pollution problems due to combined sewer overflows, which are caused by large variations in flow between dry and wet weather. This type of sewer design is no longer used in building new communities, but many older cities continue to operate combined sewers.alt

The River des Peres is listed on the Missouri Department of Natural Resources 303(d) list of impaired waters for high chloride and low dissolved oxygen with the source of impairment being urban nonpoint sources.

High chloride is likely from winter road de-icing. Low dissolved may come from combined sewage overflows and excessive lawn fertilization. Because the sources are nonpoint and therefore throughout our watershed, reducing these impairments requires that our citizens address these issues at each of their home or business. Fixes require a community effort to review and adjust the ways chemicals are used when they may come into contact with rainwater.

Metropolitan St. Louis Sewer District (MSD) is studying how our combined sewer system can be overhauled to prevent overflows, but citizens can also play a role. By educating yourself on the issues, you now know that sewer overflows happen because rainwater overloads the system. You can reduce the frequency of overflows by harvesting rainwater. Rain Barrels and Rain Gardens are simple ways you can temporarily hold water on your property to help keep the system from becoming overwhelmed. One rain garden doesn't do much, but many rain gardens can have a huge impact. Since 90% of the average annual rainfall volume occurs during rain storms of 1-inch or less, holding 1 inch of rainfall on your property helps 90% of the time! Start now and do your part to reduce pollution by installing these simple tools.

Our friends at the Deer Creek Watershed Alliance have a nice discussion on how you can reduce pollution by taking simple steps in your back yard.