The lock chamber at Lock and Dam 8, near Genoa, Wis., is dewatered in order to perform an extensive list of preventative maintenance. Rehabilitative work like this happens about every 20 years on each Mississippi River lock and dam within the St. Paul District from Upper St. Anthony Falls Lock and Dam in Minneapolis to Lock and Dam 10 in Guttenberg, Iowa. The Corps began dewatering the lock Dec. 3 in order to complete the necessary work around March 8. The anticipated cost of this project is $3.8 million. Lock and Dam 8 was last dewatered in 1992.