Floods & St. Charles County
Located at the confluence between 2 major rivers, the Mississippi River and the Missouri River, St. Charles County faces a double threat. Its residents are no strangers to flooding, ranging from seasonal "minor" floods to major floods of historic proportions, such as the Great Midwest Flood of 1993 when an estimated 40% of the county flooded.
Mississippi & Missouri Rivers
The Mississippi River is the largest river system in North America. Flowing from its source in upper Minnesota, it forms the northern boundary of St. Charles County. The Illinois River joins the Mississippi River, adding volume to the Mississippi as it flows past the northeastern portion of the county.
Starting in the Rocky Mountains of Montana and Wyoming, the Missouri River is a major river in its own right, draining approximately 1/16th of the United States. It makes up the southern boundary of St. Charles County, meeting the Mississippi at the county's eastern tip.
Together, the Mississippi River, with the Missouri River and its other tributaries, form the Mississippi River Basin, the fourth largest drainage basin in the world. In total the Mississippi River Basin drains approximately 41% of the contiguous United States, between the Rocky and the Appalachian Mountains, including 31 states and 2 Canadian provinces.