The flooding of the Redwood River historically had been a problem in Marshall. The city experienced a series of floods in the 1940s and 1950s. Diversion canals were constructed between 1961 and 1963, though occasional flooding still occurs, notably in 1993. Another project in 1997 removed of sediment from the diversion channel. The diversion channel and Redwood River underwent major upstream and downstream improvements, completed in December 2000. During the spring and fall of 2010, the Marshall area experienced unseasonably high amounts of moisture, but the Redwood River remained within its banks through town.