Zoning Codes: Flood and Seismic Adaptation Measure


Northeast Waterfront and Financial District ©trekandshoot/iStock

POLICY and EMERGENCY PREPAREDNESS
SHORELINE LOCATION:
Asset Specific




MEASURES COMPATIBILITY:
LIKELY IMPLEMENTING AUTHORITY:
Flood
Seismic
San Francisco Planning Department, BCDC
All
All


DESCRIPTION:

Zoning code updates to address coastal hazards could include:

  • Height restriction exemptions for raising buildings and/or measurement of building elevation from the DFE
  • Encouraging density/clustering of development in locations with lower risks and/or to preserve open space for flood mitigation
  • Rolling easements to restrict particular activities within the easement area (such as constructing buildings or shoreline structures) and/or the removal of existing structures within the easement
  • Building retrofit ordinances to require implementation of flood protection measures within a certain timeframe
  • Increased and/or elevated setback requirements to create a buffer from the shoreline
  • Creation of a flood risk overlay zone to account for expansion of the flood plain due to sea level rise and add requirements for protection in those areas
  • Establish minimum elevations that account for sea level rise or require floodproofing for mechanical equipment and ground floors


CONSIDERATIONS:
ADVANTAGES:
DISADVANTAGES:
  • Increased flood protection requirements in zoning codes can increase development costs, which are likely to be passed on to consumers. This could increase rents and place homeownership further out of reach for economically disadvantaged residents
  • Building code updates do not address neighborhood connectivity and transportation flooding.
  • New zoning ordinances may reduce the cost of future floods for building workers or inhabitants.
  • Relatively low cost to implement with sustained benefits over time as the waterfront is redeveloped.


  • Zoning changes or overlay zone designation that is accompanied by new land use restrictions, or will be in the future, may face legal challenges as a regulatory taking.
  • Changes in zoning generally only influence new construction and significant remodels, which means existing structures would not be protected by zoning changes.
  • Zoning changes do not ensure public safety during flood events.

CASE STUDIES:
  • The City of Goleta (CA), adopted a Hazard Zone Overlay District that imposed real-estate disclosures for coastal hazards, building code revisions, and development setbacks that account for accelerating sea level rise and erosion.
  • The City of Miami Beach has passed several zoning ordinances that increase resilience requirements (e.g., freeboard changes, grade elevations, building height)

ENVIRONMENTAL JUSTICE CONSIDERATIONS

  • Increased flood protection requirements in zoning codes can increase development costs, which are likely to be passed on to consumers. This could increase rents and place homeownership further out of reach for economically disadvantaged residents

HISTORIC PRESERVATION CONSIDERATIONS

  • Building retrofit ordinances will need to be carefully crafted to determine their applicability and appropriate implementation at historically designated sites.

UTILITY AND MOBILITY CONSIDERATIONS

  • Zoning updates do not address neighborhood connectivity and transportation flooding.

INSTALLATION AND CONSTRUCTABILITY CONSIDERATIONS

  • N/A

OPERATIONS AND MAINTENANCE CONSIDERATIONS

  • N/A


Download the Zoning Codes Factsheet.

Learn about other types of measures from our Measures Explorer page.



Northeast Waterfront and Financial District ©trekandshoot/iStock

POLICY and EMERGENCY PREPAREDNESS
SHORELINE LOCATION:
Asset Specific




MEASURES COMPATIBILITY:
LIKELY IMPLEMENTING AUTHORITY:
Flood
Seismic
San Francisco Planning Department, BCDC
All
All


DESCRIPTION:

Zoning code updates to address coastal hazards could include:

  • Height restriction exemptions for raising buildings and/or measurement of building elevation from the DFE
  • Encouraging density/clustering of development in locations with lower risks and/or to preserve open space for flood mitigation
  • Rolling easements to restrict particular activities within the easement area (such as constructing buildings or shoreline structures) and/or the removal of existing structures within the easement
  • Building retrofit ordinances to require implementation of flood protection measures within a certain timeframe
  • Increased and/or elevated setback requirements to create a buffer from the shoreline
  • Creation of a flood risk overlay zone to account for expansion of the flood plain due to sea level rise and add requirements for protection in those areas
  • Establish minimum elevations that account for sea level rise or require floodproofing for mechanical equipment and ground floors


CONSIDERATIONS:
ADVANTAGES:
DISADVANTAGES:
  • Increased flood protection requirements in zoning codes can increase development costs, which are likely to be passed on to consumers. This could increase rents and place homeownership further out of reach for economically disadvantaged residents
  • Building code updates do not address neighborhood connectivity and transportation flooding.
  • New zoning ordinances may reduce the cost of future floods for building workers or inhabitants.
  • Relatively low cost to implement with sustained benefits over time as the waterfront is redeveloped.


  • Zoning changes or overlay zone designation that is accompanied by new land use restrictions, or will be in the future, may face legal challenges as a regulatory taking.
  • Changes in zoning generally only influence new construction and significant remodels, which means existing structures would not be protected by zoning changes.
  • Zoning changes do not ensure public safety during flood events.

CASE STUDIES:
  • The City of Goleta (CA), adopted a Hazard Zone Overlay District that imposed real-estate disclosures for coastal hazards, building code revisions, and development setbacks that account for accelerating sea level rise and erosion.
  • The City of Miami Beach has passed several zoning ordinances that increase resilience requirements (e.g., freeboard changes, grade elevations, building height)

ENVIRONMENTAL JUSTICE CONSIDERATIONS

  • Increased flood protection requirements in zoning codes can increase development costs, which are likely to be passed on to consumers. This could increase rents and place homeownership further out of reach for economically disadvantaged residents

HISTORIC PRESERVATION CONSIDERATIONS

  • Building retrofit ordinances will need to be carefully crafted to determine their applicability and appropriate implementation at historically designated sites.

UTILITY AND MOBILITY CONSIDERATIONS

  • Zoning updates do not address neighborhood connectivity and transportation flooding.

INSTALLATION AND CONSTRUCTABILITY CONSIDERATIONS

  • N/A

OPERATIONS AND MAINTENANCE CONSIDERATIONS

  • N/A


Download the Zoning Codes Factsheet.

Learn about other types of measures from our Measures Explorer page.