Lakes in Union County, Iowa      Green Valley Lake Lake Afton Lake McKinley Spring Valley Lake Summit Lake Thayer Lake Three Mile Lake Twelve Mile Lake OTHER COUNTIES NEARBY Adair County Adams County Audubon County Carroll County Cass County Clarke County Dallas County Decatur County Guthrie County Lucas County Madison County Page County Polk County Pottawattamie County Ringgold County Taylor County Warren County Gentry County Grundy County Harrison County Holt County Mercer County Nodaway County Putnam County Sullivan County Worth County Iowa Lakes