Recent record-setting heat is causing serious problems in some parts of the country; recent pavement blowups in Iowa have forced the Department of Transportation to issue a warning to motorists, urging them to pay special attention to pavement surfaces when driving in temperatures above 90 ° F.
Pavement blowups occur when a wet period is followed by periods of extreme heat. Water stays in the cracks in pavement surface, then thermal expansion forces the pavement to buckle and shatter. The blowups pose a safety risk for motorists as well as costing the state additional money for repairs. The Iowa Department of Transportation estimates that pavement blowups cost the state $400,000 annually in road repair as well as an additional 2-4,000 hours of manpower making temporary repairs.
Motorists are urged to use caution and reduce speed when approaching broken pavement areas.