In Nebraska, UP raised seven miles of track near Ogallala.
Union Pacific railroad is repairing flood-damaged tracks in Colorado, and working to protect its main line crossing Nebraska as floodwaters flow east into the Plains.
Union Pacific spokesman Mark Davis says flooding damaged about 20 miles of its line west over the mountains out of Denver and damaged another 19 miles of track between Denver, Colorado and Cheyenne, Wyoming.
Davis says the north-south track was expected to reopen Wednesday afternoon, but the line over the mountains will likely be closed for repairs until October 1st.
UP is rerouting the 10 trains a day that normally use that line, and Amtrak is busing passengers over the mountains.
In Nebraska, UP raised seven miles of track near Ogallala 4 inches and piled rock along tracks between Julesburg, Colorado and Big Springs, Nebraska.