Gov. Mike Johanns said the storms that pummeled southeast Nebraska caused $8.5 million in damage to public property.
He said it will be sometime before an estimate is available for damage to homes and private property.
Meanwhile, President Bush approved Johanns' request to declare Lancaster, Cass Gage and Saline Counties as disaster areas.
Johanns stressed that other counties could be added to the list. Saturday's storms spawned 19 confirmed tornadoes, killed a 73-year-old Hallam woman and injured 37 people. They also destroyed 158 homes and damaged at least 57 others in Lancaster, Saline, Gage and Cass counties. Norris High School near Firth also sustained heavy damage.
Hardest hit was the village of Hallam, south of Lincoln, nearly every structure in the town of 276 was damaged.
Nearly 500 volunteers showed up Tuesday to help with the recovery effort.