DULUTH, MN (KDAL) - The spring runoff of melting snow has caused water levels to rise on many streams and ditches in St. Louis County. At least five roads have been closed and several others are being monitored by Public Works crews. Signs are posted and motorists are reminded that the roads could be closed for several days. Warning signs are also up on roads that have water on the roadway but remain open. Caution is advised because water levels can change rapidly.