FEMA Mapping Process

FEMA Releases Preliminary Revised Yolo Flood Maps

The Federal Emergency Management Agency (FEMA) is revising the county’s Flood Insurance Rate Maps (FIRMs), including the map panels for the City of Davis. These map the Special Flood Hazard Areas (SFHAs). The SFHAs are FEMA’s determination of property that has a 1% chance of flooding in any given year. The SFHAs, or so-called “100-year flood” designation, is the criteria banks must use when the mortgages are backed by a Federal loan program. In these cases, homes within the flood hazard area must have flood insurance, through the federal flood insurance program. Even if the mortgage is not through a federal loan program, lenders may require flood insurance, if their policies so provide.

Yolo County is in a natural floodplain. SFHAs run along the Colusa Basin Drain near Dunnigan and Knights Landing, Cache Creek and the Sacramento River, including the Yolo Bypass. In the City of Davis, south of I-80, the current “100 year” SFHAs stop at the west levee along the Yolo Bypass.

As a result of levee failure and severe floodwater damages sustained nation-wide, FEMA requires certification of existing levees to meet or exceed quality standards established in 1986 for design and maintenance. As a result, even though the quality of the local levees hasn’t changed, none of the Yolo County levees met certification standards prior to the deadline for the current mapping effort, and this will result in tens of thousands of people throughout Yolo County being required to obtain flood insurance by spring 2010.

In addition to FIRM revisions due to the lack of levee certification, there are other map changes shown in the preliminary maps as a result of changing from an earlier map format to a digital format (DFIRM). Local agencies, including City of Davis, are working with FEMA to ensure accuracy. FEMA will evaluate the information provided by the local agencies, and intends to issue the official DFIRMs in September 2009. Once they have issued the maps, they will become effective six (6) months later, anticipated to be March 2010.

To see the Preliminary FEMA Flood Insurance Rate Maps, visit http://www.map9-m.com/projects/yolo/MAPIX-M-RegionIXCoordinationSite--YoloCountyCA.shtm


City of Davis, California
23 Russell Blvd.
Davis, Ca. 95616