English: Des Moines, Iowa, July 24, 2004 -- This tornado shelter for 400 campers at the Iowa State Fairgrounds outside Des Moines was completed in 2003. The 5,200 square-foot shelter is 100 feet long by 71 feet wide. When not in use as an emergency shelter, the large multi-purpose building is used by both the fairground staff and campers for restrooms, showers, a laundry area, offices, and meeting space. The shelter, funded through a $600,000 grant from FEMA's Hazard Mitigation Grant Program with the Iowa State Fair funding the remaining $150,000. In June 1998, a storm with winds in excess of 100 miles per hour (mph) caused over $465,000 in damage to the State Fair complex, severely impacting the campground with fallen trees and limbs. Fortunately, no one was hurt during this event, but the potential for disaster and loss of human life was obvious.

The roof and the unique curved walls of the structure are constructed of 12- inch-thick, precast concrete panels. The concrete uses a special formwork that retains the overall curved shape. The pie-shaped panels enable the roof to be the required width without exceeding a maximum span of 32 feet. The roof and wall panels are connected with welded steel plates. On the east side of the structure, a concrete canopy mounted on concrete piers provides weather protection. The canopy has been designed to withstand 250-mph winds and to prevent them from becoming a debris hazard themselves during a high-wind event. A future canopy on the west side is planned to cover the entry to the shelter from the road. The canopy on the east side of the shelter provides cover for gatherings at the campground such as small musical groups and social events; descending steps radiating from beneath the canopy promote its use as a stage.

FEMA Photos/Tom Hurd