Description: The official FEMA floodplain for crook County. Used by the crook County planning to see if a property is close to the flood plain (100year is the category that is important for most decisions). The 100 year floodplain = 0.2 PCT ANNUAL CHANCE FLOOD HAZARD. This was provide by FEMA and was part of the orriginal FEMA floodplain maps and updated with site specific revisions.