The Missouri Department of Conservation is working with natural flooding cycles to eventually build up and stabilize the access.
The Missouri Department of Conservation (MDC) has closed Truman Access on the Mississippi River in Jefferson County to public use until further notice due to flood damage. According to a release on Thursday, MDC intends to harness the natural flooding cycles to eventually accumulate enough silt to utilize in making the flood-prone access more resistant to overtopping.
Truman Access is extremely susceptible to flooding. Flood events over the last several years have continually destroyed MDC’s efforts to regrade and re-rock the access and parking lot, including trucking away sentiment only to have more deposited again during flooding.
“The flood from last summer deposited anywhere from 2-to-6 feet of sediment over the entire access area and parking lot after being under water for many weeks,” said MDC St. Louis Regional Infrastructure Maintenance Supervisor Mike Norris. Norris went on to note that MDC lost all the surface rock it installed, and that this cycle has occurred every time the river has flooded in recent years.
However, MDC St. Louis Regional work crews are planning to turn the problem into its own solution.
Elsewhere in the state, MDC crews have found success with river access in similar situations by “going with the flow.” The strategy is to close an access for a period of time, allowing an ample amount of sediment and silt to build up over multiple flood events. Construction crews have then used the deposits as building material to shore up the accesses. The existing silt is bulldozed into place, graded, and surfaced with rock. This has proved successful in raising the accesses high enough, so they are no longer susceptible to overtopping.
“We have worked this strategy at a river access in southeast Missouri that was in the same situation as Truman and they were able to raise the elevation there after a few years. Now the frequency of the river overtopping it has been reduced significantly,” Norris explained.
Like much in natural resource management, the strategy does require time and patience to enact. Norris said that MDC will reevaluate the situation at Truman access on an annual basis to determine when the accumulation of sediment would be enough to rebuild the access. Norris estimates the earliest window to begin work might be January 2022, depending on flood activity.
During the Truman Access shut down, river users should consider the following alternative access point:St. Mary’s Access, down river of Truman Access in Ste. Genevieve County. This access is south of the Highway 61/Route U junction on the east side of Highway 61. Users should note that when the Chester river gauge reads 24.5, water covers the parking area.
Additionally, due to this closure the U.S. Fish and Wildlife Service’s nearby Harlow Island Access, is accessible by foot only with no parking available.
For updates on Truman Access, visit MDC’s online atlas at https://short.mdc.mo.gov/ZLc.