Overview on Flooding
Anywhere it rains, it can flood. Flooding is the most common and costly disaster in the United States resulting in billions of annual property damage and one of the highest losses of life due to natural disaster. The National Flood Insurance Program (NFIP), established in 1968, is a voluntary Federal program that enables property owners in participating communities to purchase insurance protection against losses from flooding. It is important for the City of Murfreesboro landowners to understand the effects flooding may have on their lives and property so that they can make informed decisions on purchasing or renting properties located in flood prone areas, purchasing flood insurance, what can be done to reduce flood damage and how they can prepare for flood events.
The City of Murfreesboro is located within the Stones River Watershed that has a drainage area of 556.2 square miles inside the entire county. The most critical flooding period is December through April, when frequent, widespread, high-intensity storms take place. The major flooding sources in the City are sinkhole flooding, the West Fork Stones River and Lytle Creek. Flooding can also occur in areas away from waterways during extreme weather events. Sinkholes and other geologic features that are commonly used for stormwater runoff storage and disposal may flood when significant rain events overwhelm the handling capacity of these features.
Floods of large magnitude have occurred in the vicinity of Murfreesboro and have caused extensive damage to bridges, highways, railroads, homes, businesses, farm lands, and public facilities. These floods occurred in 1902, 1944, 1945, 1948, 1955, 1963, and 1975; each having estimated peak discharges in excess of 20,000 cubic feet per second (cfs) (FIS 2008).
Todds Lake Sinkhole flooding is a major problem in Murfreesboro. Flooding in the sinkhole region occurs when large depressions in the natural ground, with little or no outlets, simply store the rainwater. During the flood of March 1975, 12 homes on Johnson Street were damaged by sinkhole flooding, with a water depth reaching nearly 7 feet on the first floor.
West Fork Stones River At the Murfreesboro gage, the West Fork Stones River has risen over 15 feet in less than 12 hours during several major floods. The other relatively smaller streams in Murfreesboro rise even faster than West Fork Stones River and reach flood peaks in only a few hours.
The maximum flood stage recorded on West Fork Stones River occurred on February 13, 1948, reaching at stage of 22.73 feet NGVD, with an estimated peak discharge of 38,000 cfs. The March 28, 1902 flood stands as the highest known flood. This flood crested at 25.0 feet NGVD with an estimated peak discharge of 50,000 cfs. Velocities of water during major floods range up to 12 fps (approximately 8 miles per hour) in the channel. Velocities in the floodplain vary widely, depending on location, but generally are less than 4 fps. (FIS 2008).