Gates and Barriers: Flood Adaptation Measure


The Foss Barrier, a 16 tonne gate built in 1989, is lowered into the River Foss
to stop the Foss levels from rising flood waters on the River Ouse - York, England
©Michael Jagger/Foss Flood Barrier/CC BY-SA 2.0



PHYSICAL INFRASTRUCTURE
SHORELINE LOCATION:
In Water




DESIGN LIFE
ADAPTABILITY
IMPACT ON THE WATERFRONT
CONSTRUCTION COST
50+ Years
Low
Major Intervention
TBD


COASTAL FLOOD HAZARDS MITIGATED:
Sea Level Rise
Storm Surge
Groundwater
Waves
Erosion


MEASURES COMPATIBILITY:
ECOSYSTEM SERVICES: Measure may affect these shoreline values
Flood
Seismic
Levee, Offshores Seawall, Floodwalls
All
Aquatic Habitat
Terrestrial Habitat
Water Quality
Carbon Storage


DESCRIPTION:
A flood barrier, surge barrier or storm surge barrier is a specific type of floodgate, designed to prevent a storm surge or king tide from flooding the protected area behind the barrier. The gates most often remain open and allow passage of water between the mouth. Gates and barriers come in many forms and types which are suitable for different opening widths and required vessel drafts.


CONSIDERATIONS:
ADVANTAGES:
DISADVANTAGES:
  • Signifcant structure with large impact on waterfront.
  • Would need to be paired with adjacent shoreline protection to prevent outflanking.
  • Potential opportunity for urban design improvement with creek crossing.
  • Limited applicability to coastal storm risk faced within the Bay (assuming closure for daily high tides is not tenable).
  • High cost and environmental impact.
  • Potential upland stormwater discharge impacts.
  • May cause water quality concerns within closed creeks.


CONSTRUCTION IMPACTS TO THE PUBLIC:
SEA LEVEL RISE ADAPTATION OPPORTUNITIES:
CASE STUDIES:
  • Dependent on location and siting.
  • Impacts could be significant if located near shore, or less if in offshore location.
  • Limited adaptability.
  • Could be paired with deployables and shoreline floodwalls as additional protective elements.
  • Lake Borgne Storm Surge Barrier, New Orleans
  • Maeslantkering Storm Surge Barrier, Netherlands
  • Venice MOSE, Italy.


DESIGN OPPORTUNITIES:
Ecological Enhancements
Urban Design
Form
  • N/A
  • N/A
  • N/A


DESIGN CONSIDERATIONS:

  • Requires tie into cut-off wall that will disrupt the water column and allow for full closure in the event of a storm surge or king tide.
  • High seismic region will provide a challenge to maintain operability of the gates in the event of moderate to high seismic event.
  • Need to ensure circulation of natural channels is not lost, which may require supplemental pumping to move water and sediment.
  • Extensive permitting process and high level of environmental study.

SITE-SPECIFIC CONSIDERATIONS:

  • Siting requires recognizing federally navigable channels at Mission and Islais Creek.

URBAN DESIGN CONSIDERATIONS:

  • Closure structures could provide pedestrian cycling access. While closed, closure structures would prevent navigation from the creek to the Bay.

INSTALLATION AND CONSTRUCTABILITY CONSIDERATIONS:

  • Costly installation with long lead time and overall construction duration.

ARCHITECTURAL CONSIDERATIONS:

  • Significant visual impact on current shoreline.
  • Certain types of gates could be made publicly accessible which could provide opportunity for creek crossing.

HISTORICAL RESOURCE CONSIDERATIONS:

  • Abutments for gates would need to recognize adjacent historic resources and account accordingly.

OPERATION AND MAINTENANCE CONSIDERATIONS:

  • Extensive maintenance and monitoring costs require active operation to ensure they are utilized when needed to protect infrastructure upland.


Download the Gates and Barriers Factsheet.

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


The Foss Barrier, a 16 tonne gate built in 1989, is lowered into the River Foss
to stop the Foss levels from rising flood waters on the River Ouse - York, England
©Michael Jagger/Foss Flood Barrier/CC BY-SA 2.0



PHYSICAL INFRASTRUCTURE
SHORELINE LOCATION:
In Water




DESIGN LIFE
ADAPTABILITY
IMPACT ON THE WATERFRONT
CONSTRUCTION COST
50+ Years
Low
Major Intervention
TBD


COASTAL FLOOD HAZARDS MITIGATED:
Sea Level Rise
Storm Surge
Groundwater
Waves
Erosion


MEASURES COMPATIBILITY:
ECOSYSTEM SERVICES: Measure may affect these shoreline values
Flood
Seismic
Levee, Offshores Seawall, Floodwalls
All
Aquatic Habitat
Terrestrial Habitat
Water Quality
Carbon Storage


DESCRIPTION:
A flood barrier, surge barrier or storm surge barrier is a specific type of floodgate, designed to prevent a storm surge or king tide from flooding the protected area behind the barrier. The gates most often remain open and allow passage of water between the mouth. Gates and barriers come in many forms and types which are suitable for different opening widths and required vessel drafts.


CONSIDERATIONS:
ADVANTAGES:
DISADVANTAGES:
  • Signifcant structure with large impact on waterfront.
  • Would need to be paired with adjacent shoreline protection to prevent outflanking.
  • Potential opportunity for urban design improvement with creek crossing.
  • Limited applicability to coastal storm risk faced within the Bay (assuming closure for daily high tides is not tenable).
  • High cost and environmental impact.
  • Potential upland stormwater discharge impacts.
  • May cause water quality concerns within closed creeks.


CONSTRUCTION IMPACTS TO THE PUBLIC:
SEA LEVEL RISE ADAPTATION OPPORTUNITIES:
CASE STUDIES:
  • Dependent on location and siting.
  • Impacts could be significant if located near shore, or less if in offshore location.
  • Limited adaptability.
  • Could be paired with deployables and shoreline floodwalls as additional protective elements.
  • Lake Borgne Storm Surge Barrier, New Orleans
  • Maeslantkering Storm Surge Barrier, Netherlands
  • Venice MOSE, Italy.


DESIGN OPPORTUNITIES:
Ecological Enhancements
Urban Design
Form
  • N/A
  • N/A
  • N/A


DESIGN CONSIDERATIONS:

  • Requires tie into cut-off wall that will disrupt the water column and allow for full closure in the event of a storm surge or king tide.
  • High seismic region will provide a challenge to maintain operability of the gates in the event of moderate to high seismic event.
  • Need to ensure circulation of natural channels is not lost, which may require supplemental pumping to move water and sediment.
  • Extensive permitting process and high level of environmental study.

SITE-SPECIFIC CONSIDERATIONS:

  • Siting requires recognizing federally navigable channels at Mission and Islais Creek.

URBAN DESIGN CONSIDERATIONS:

  • Closure structures could provide pedestrian cycling access. While closed, closure structures would prevent navigation from the creek to the Bay.

INSTALLATION AND CONSTRUCTABILITY CONSIDERATIONS:

  • Costly installation with long lead time and overall construction duration.

ARCHITECTURAL CONSIDERATIONS:

  • Significant visual impact on current shoreline.
  • Certain types of gates could be made publicly accessible which could provide opportunity for creek crossing.

HISTORICAL RESOURCE CONSIDERATIONS:

  • Abutments for gates would need to recognize adjacent historic resources and account accordingly.

OPERATION AND MAINTENANCE CONSIDERATIONS:

  • Extensive maintenance and monitoring costs require active operation to ensure they are utilized when needed to protect infrastructure upland.


Download the Gates and Barriers Factsheet.

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