The Federal Emergency Management Agency is working on floodplain maps for the Lewis & Clark and Big Sioux watersheds. That is partly a follow up to the massive Missouri River flooding in 2011 when no accurate river elevations were available.
Joe Morrow is the flood plain administrator for the City of Yankton.

The Lewis & Clark Watershed extends ninety nine miles from Gavins Point Dam to Sioux City. Morrow says the new maps should give them more accurate information.

Morrow says after the maps are produced, there will be hearings and public input.

The mapping project is a FEMA requirement for participation in the national flood insurance plan.