The St. Paul District of the U.S. Army Corps of Engineers will soon close three of its upper Mississippi River locks and dams north of Guttenberg, Iowa, to navigation, regardless of weather, for winter maintenance. The district's other 10 locks, all north of Guttenberg, are expected to close before then due to weather conditions. Lock and Dam 3, north of Red Wing, Minn., will close Dec. 1 until March 15, allowing the Corps to dewater and perform major maintenance.

Lock and Dam 5A, near Fountain City, Wis., will close Dec. 3 until March 1 for the installation of bulkhead slots. Lock and Dam 10, in Guttenberg, will close Dec. 8 until March 1 for continued major maintenance and rehabilitation. The St. Paul District operates and maintains 13 locks and dams on the Mississippi River, beginning at Upper St. Anthony Falls in Minneapolis and ending at Lock and Dam 10 in Guttenberg.

PAUL WALSH