Sometimes it rains, and sometimes it pours and late spring has brought many significant rainfall events to Iowa this year. We have seen weather from groupings of severe thunderstorms, to tornadic activity in the month of May and then followed by remnants of Tropical Storm Cristobal this week. It is safe to say Iowa has had no lack of rainfall.
Significant rain events are often followed by flash floods. These floods can quickly overrun the capacity of Iowa’s streams and rivers. Pictured here, is the aftermath of heavy downpours and tornadic activity in Jackson County, Iowa. This is from May 23, 2020. As you can see Cedar Creek was quickly overrun by 1.5 to 3 inches of rainfall that fell in its watershed within the duration of one hour!
How can wetlands provide flood mitigation?
During flood events, wetlands often provide significant amounts of flood mitigation in many forms.
Here are some of the ways that wetlands help with flood events:
- Wetland plants including root clusters, trees, and other vegetation lessen erosion. They also slow the speed of floodwaters by dissipating water across larger areas.
- Wetlands provide significant amounts of water storage and reduce the spread and overall height of floodwaters.
- One acre of wetlands can store between 1 to 1.5 million gallons of water.
- Wetlands reduce damage to surrounding infrastructure and agriculture by providing a buffer between them and the surrounding water bodies.