Water Quality

St. Charles County is among the fastest growing areas in the United States. What was just a few years ago forest, farmland or open prairie is now experiencing rapid development. The county's numerous public water providers currently serve a majority of county residents. The U.S. Environmental Protection Agency and the State of Missouri Department of Natural Resources strictly regulate public water providers.

Keeping Our Water Clean

Pure water is essential to all life on Earth, which — like our bodies — is 70 percent water. Here are tips that you and your family or business can follow to help keep our water clean:

  • Prevent erosion (sediment is the #1 pollutant of local waterways).
  • Properly dispose of waste and pick up litter that may end up in local waterways.
  • Never pour chemicals or hazardous materials on the ground or into sewers.
  • Landscape with native plants to minimize the need for fertilizers and pesticides.
  • Protect wetlands, which serve as a buffer against pollutants, erosion and flooding.
  • Report any suspicious dumping or activity to the Division of Environmental Health and Protection at 636-949-1800.
  • Form a Stream Team in your community.

Drinking Water

The majority of St. Charles County residents have public water, which comes from alluvial wells near the Missouri or Mississippi rivers. Some households have their own private wells, which use groundwater aquifers. Either way, each of us plays an important role in conserving and protecting our local water supply.

Streams & Watersheds

Everyone lives in a watershed, the land that drains into a stream, creek, river or ocean. Watersheds come in different sizes and shapes. Within each watershed, all water runs to the lowest point-a stream, river, or lake. Water travels over the surface across farms, streets, and suburban lawns, or it seeps into the soil and travels as groundwater. Large watersheds like ones for the Mississippi River and Missouri River are made up of many smaller watersheds, such as the Dardenne, Femme Osage and Big creeks here in St. Charles County.


Stormwater is generated by water runoff from land and impervious areas (streets, lawns, farms, parking lots, rooftops, construction sites, etc.). Stormwater pollution is caused by our daily activities. Rain and snowmelt run off and pick up oil, fertilizers, pesticides, dirt and other pollutants on the way to our creeks, rivers and lakes. According to the U.S. Army Corps of Engineers stormwater runoff is our most common cause of water pollution, which can make it unsafe for drinking, fishing or swimming.

ProblemEffect on Water QualityEasy Solutions
Lawn Care Products
  • Fertilizer accelerates growth of aquatic plant life, which robs waterways of oxygen when they decay.
  • Pesticides and herbicides create adverse effects on fish and water bugs, a vital component of aquatic food chain.
  • Don't apply lawn chemicals just before it rains. Follow instructions on the label carefully to prevent over-application.
  • Target your use of pesticides, herbicides and fertilizer; sweep up excess if it's in solid form.
  • Use native vegetation and grasses that don't require as much fertilizer and water! Visit Grow Native!
  • Bring your old chemicals to a free chemical collection!
Cleaning ProductsCleaning products (including those you might use to wash your car) are toxic to fish, stimulate algae and plant growth, and upset the ecosystem by impacting animal life.Use a commercial car wash, or wash your car on the lawn with a biodegradable soap.
Yard Waste
  • Grass clippings, leaves and flowers clog storm drains, cause erosion along stream banks, and robs streams of oxygen as they decay.
  • Dirt, dust and sand bury fish food and cloud the water, affecting the ability of fish to feed.
  • Mulch or compost your yard clippings.
  • Sweep dirt onto the lawn.
  • Place debris in the trash.
Pet WastePet waste releases bacteria, diseases and viruses into streams where our children play.Pick-up pet waste. Flush it down the toilet or bag it and place in the trash.
Paint & Automotive Fluids
  • Dyes and paints can interfere with the ability of fish to breathe, plants to grow, and water bugs to reproduce.
  • Antifreeze is poisonous to plants and animals, and seriously depletes oxygen in the water.
  • Paint, dirt, dust and dyes can damage fish gills, as well as reduce growth and reproduction of fish and other aquatic organisms.
  • Never pour these down a storm drain or into a gutter!
  • Dispose of dry and/or empty oil-based and water-based paint containers and brushes in the garbage.
  • Bring oil, antifreeze and other hazardous fluids to Recycle Works for proper disposal.
  • Bring excess fertilizer, pesticides, paint and other chemicals to Recycle Works for proper disposal.
  • Keep cars and gas-powered lawn mowers or blowers well-tuned, so they are not dripping toxic fluids or emitting toxic fumes.