Simi Valley residents will get their first look tonight at a map that shows which areas of the city would be threatened by a once-in-a-century flood, and whose insurance requirements might rise as a result.
The new flood plain map, produced by the Federal Emergency Management Agency, shows where flooding would occur when water rises to a level it is expected to reach only once every 100 years. The map is tentative, and FEMA is not expected to adopt a final version until October.
Neither FEMA nor the city has calculated the acreage of the newly measured flood plain, nor the number of people living in it.
A 1974 study by the U.S. Army Corps of Engineers showed that 250 Simi Valley residences are in the flood plain. But because of growth and topographical changes, "now, we're talking about many thousands," Mike Kuhn, senior planner for the city, said.