Current Situation: Parts of Woodland are in the 100 year floodplain for Cache Creek. The Federal Emergency Management Agency (FEMA) provides Flood Insurance Rate Maps (FIRMs) which show their determination of the boundaries of the 100 year flood. (A "100 year" flood has a 1/100 chance of occurring in any given year.) For the most part, the flooding projected for Woodland is shallow sheet flooding with depths generally less than two to three feet. This is significantly different than parts of Sacramento, which can experience depths over ten feet. The current FIRMs affecting areas around Woodland show the 100 year floodplain to be east of College and north of Clover Street.
200 Year Floodplain Depth Map
Effect of Being in a Floodplain: The FEMA floodplain is important because any new building (or building undergoing significant remodeling) within the 100 year floodplain must comply with special provisions in the Building Code (primarily that the first floor must be above the base flood elevation). Additionally, federally insured mortgages on buildings in the floodplain must have flood protection insurance (premiums are generally about $300-$400 per $100,000 assessed valuation).
Army Corps Study Findings: The Army Corps of Engineers completed a study of the Cache Creek floodplain and identified possible flood protection projects several years ago. The Cache Creek levees have a ten year level of protection (meaning 1/10 chance of breaching the levees each year). While they concluded the floodplain was more extensive than originally thought (generally the area north of Woodland Avenue from County Road 98 to East Street then generally north of Gum Avenue from East Street to County Road 102), there was little interest voiced during the related public workshops for proceeding with the projects. The local cost share was estimated at $10 million. While this study did not officially change the FEMA determination of the floodplain, it should be viewed as a matter of some concern.
Flood Insurance Rate Map (FIRM): A FIRM was issued in May 2012. Copies are available for public inspection at the Community Development Department, 300 First Street.
Flood Protection Initiatives: The City of Woodland, the state Department of Water Resources, and the Corps of Engineers are coordinating on a $3.0 million flood protection "Feasibility Study" to determine a preferred flood protection alternative for Cache Creek. The study is scheduled for completion in June 2016.