Where is the South Grand River Watershed?

If you live in Cass County, Missouri, chances are that you live in the South Grand River watershed? Most of Cass County, along with portions of seven other Missouri counties and two in Kansas, lie within this watershed of more than 2,000 square miles. Many smaller watersheds (East Creek, Massey Creek, Middle Big Creek, Big Creek, Crawford Creek, Camp Branch, Poney Creek, Tennessee Creek, Eightmile Creek, Sugar Creek, Rocky Branch, North Sugar Creek, Mormon Fork, Walnut Creek, Knob Creek, Lick Branch, East Branch South Grand River, and South Fork South Grand River in Cass County) drain into the South Grand River which in turn empties into the Truman Reservoir.

Each of these small watersheds is also made up of even smaller watersheds—such as a small ditch or low-lying grassy field. These are known as the headwaters. Water begins its journey in a watershed via these headwater streams. They often have water in them only during times of rain but, if they are fed by a groundwater source, may contain water at other times as well. These small waterways and their role in the watershed are often not understood or recognized and, as a result are routinely severely impacted by human activity. However, they are crucial to the quality of water in the entire watershed and it is essential that they be protected and restored for their significant function in the watershed.

High quality riparian corridors (buffer zones) of natural vegetation along the headwater stream serve to filter out sediments and other pollutants, slow the stormwater so they can infiltrate into the groundwater, reduce flooding downstream, and provide essential habitat for a number of species. If there is a quality riparian corridor, the journey of the waters has a quality beginning. However, if the riparian corridor has been removed and replaced with impervious surfaces such as parking lots, streets, rooftops and urban lawns or plowed fields, the resulting runoff will carry sediments and pollutants of many types and water quality will be impaired throughout the system.

Since headwater streams make up at least 75% of a watershed, it is easy to see that they have an impact on the quality of water in our rivers. Degradation of water quality can be minimized by protecting existing riparian corridors of native vegetation and by restoring these corridors where they have been eliminated. Practices such as Low Impact Development, bio retention areas in parking lots, rain gardens, and using native plants in landscaping are also practices that can reduce contaminated runoff. Individual actions such as reducing use of chemicals on lawns and agricultural crops are other practices that can reduce harmful impacts to our water resource.

As John Muir, naturalist and conservationist said. “When one tugs at a single thing in nature, he finds it attached to the rest of the world.” This is certainly true of our headwater streams. If we work together to protect them, we will also be protecting the water in our rivers, lakes, and groundwater.

Learn more at www.sgrwa.org