Floodplain Ordinance Amendment
Public Works Department
City Council
May 7, 2024
Purpose of Revision
• Wholesale Rewrite based on Model Ordinance from
State Department of Water Resources
• Meet Community Rating Service Requirements
• Conforms to California Building Code
• Implement Climate Adaptation and Resiliency Plan
• Implement the General Plan Safety Element
National Flood Insurance Program
• FEMA Administered Program
• Provides flood insurance and disaster assistance
to all Alameda residents
• Over 1,000 Structures in 100-year Floodplain
• New or Substantially Improved structures must
minimize flood risk
• All Federally backed mortgages in the floodplain
must have flood insurance
Flood Zones in Alameda
Blue - 100-year Floodplain, ~El. 10ft
Regulated Floodplain
Brown - 500-year Floodplain, ~El. 11ft
Risk Assessment, Insurance Premium
Fernside Blvd
East Shore Dr
Beach Rd
Maitland Dr
Flood Zones in Alameda
Fernside Blvd
East Shore Dr
Beach Rd
Maitland Dr
Blue - 100-year Floodplain, ~El. 10ft
Regulated Floodplain
Brown - 500-year Floodplain, ~El. 11ft
Risk Assessment, Insurance Premium
Community Rating System (CRS)
• Voluntary Program to exceed NFIP minimums
– Education and Outreach
– Preservation of Open Space
– Increased Standards
• Alameda is a Class 8 Community - 10% discount
• 1-foot freeboard (~El. 11 ft) requirement
• Alameda is recertifying our CRS in 2024, must revise
Floodplain Ordinance to maintain Class 8 rating
NFIP , CARP, and Sea Level Rise
• FEMA Flood Maps DO NOT account for Sea Level Rise
• Should we protect to a higher elevation (i.e. El. 12ft)? – Substantially expanded area (500-yr floodplain)
– Small fraction of homes protected
• Part of larger discussion about Sea Level Rise
• Recommend to Revisit at future CRS Recertification
Substantive Changes
• Incorporate California Building Code requirements
– New or SI Structures elevated 1-foot above the BFE (~El. 11ft) – No practical change, 2018 CBC requirement
• Define Substantial Improvements to be cumulative over a 5-year period (CARP strategy, CRS credit)
• Require a Non-Conversion Agreement (CRS credit)
Recommendation
• Introduce an Ordinance Amending the
Alameda Municipal Code and Adopting a
New Chapter XX, Floodplain Management
9