( CNN ) -- At least 200 structures have been destroyed and 1,100 damaged after a dam on an eastern Iowa lake failed , unleashing a torrent of floodwaters , a spokesman for the governor said Sunday . The Lake Delhi dam , about 45 miles north of Cedar Rapids , failed Saturday as a result of `` massive rain -- a very unusually high amount this season , '' according to Jim Flansburg , communications director for Gov . Chet Culver . It was unclear how many of the structures impacted by the ensuing floodwaters were residential homes , Flansburg said . Culver planned to tour the affected areas Sunday afternoon , helping set sandbags out to stave off the rising Maquoketa River . Culver told CNN Saturday that nearly 10 inches of rain had recently fallen in a 12-hour period in the area and was `` too much water for the dam to hold . '' The roads on either side of the dam -- which were part of the cement dam 's containment measures -- apparently gave out as a result of the rainfall , Flansburg said . Video on Saturday showed massive amounts of water violently gushing from the pool behind the dam into the Maquoketa below . Nearby homes and buildings were under water up to their eaves . No injuries were reported .
It 's unclear how many of the affected structures are residential homes . The Lake Delhi dam failed Saturday as a result of heavy rainfall in the region . Iowa Gov . Chet Culver will tour the affected region Sunday . No injuries were reported in the flooding .