Eelgrass Restoration

Measure under the Aquatic Habitat measures related to ecological infrastructure opportunities to address flood risk

Looking for more? Head back to the Measures Explorer to check out other flood and seismic measures.


Eelgrass bed in New England ©Cornell Cooperative Extension Marine Program
DESCRIPTION:
Eelgrass is a flowering underwater plant that exists completely submerged. Growth of eelgrass improves water quality as well as transparency by trapping and storing particles and dissolved nutrients. Eelgrass growth can result in wave attenuation, bottom stabilization and habitat creation.





ECOLOGICAL INFRASTRUCTURE:
WATER LEVEL RANGE: Intertidal to subtidal

SHORELINE LOCATION:
In Water




DESIGN LIFE:
ADAPTABILITY:
IMPACT ON THE WATERFRONT:
CONSTRUCTION COST:
N/A
High
Minor Intervention
TBD




COASTAL FLOOD HAZARDS MITIGATED:
Enhancements can provide flood protection when combined with other physical infrastructure





Sea Level Rise
Storm Surge
Groundwater
Waves
Erosion




MEASURES COMPATIBILITY:
ECOSYSTEM SERVICES: Measure may affect these shoreline values






Flood
Seismic
Vegetated Terraces, Revetments, Levees
N/A
Aquatic Habitat
Terrestrial Habitat
Water Quality
Carbon Storage




CONSIDERATIONS:

ADVANTAGES:

DISADVANTAGES:





  • Eelgrass beds provide a number of ecological benefits but require considerable labor and time to install and monitor.
  • Feasible sites have soft substrates, low wave energy, shallow elevation, and suitable water quality (salinity, turbidity).
  • Migration pathways for eelgrass beds should be considered in anticipation of sea level rise.

  • Eelgrasses provide wave attenuation and bottom stabilization with no additional installation of infrastructure.
  • Increase biodiversity and provides marine habitat.

  • Potentially significant construction cost.
  • Potential long-term monitoring.




CONSTRUCTION IMPACTS TO THE PUBLIC:

SEA LEVEL RISE ADAPTATION OPPORTUNITIES:

CASE STUDIES:





  • Feasible locations are generally distanced from marine traffic. Because installation and monitoring would likely occur outside of marine traffic areas and from the water, construction impacts to the public would likely be negligible.

  • Adaptable to water levels. Will migrate as water levels change if an adequate migration pathway is present.

  • None cited




DESIGN OPPORTUNITIES:





Ecological Enhancements

Urban Design

Form
  • Measure is an ecological enhancement.

  • Eelgrass beds can attract recreational water users seeking to view wildlife.

  • Form is subject to environmental conditions, and largely invisible to the public.




DESIGN CONSIDERATIONS:

  • Eelgrass will require certain design considerations to be successful, including focus on performance factors such as waves, currents, tides, turbidity, water quality, and salinity conditions.


SITE-SPECIFIC CONSIDERATIONS:

  • Water levels, waves, and currents should be well defined. Eelgrasses prefer shallow waters and low energy wave environments.
  • Eelgrass requires a soft substrate (fine gravel, sand, mud) to root.


INSTALLATION AND CONSTRUCTABILITY CONSIDERATIONS:

  • Initial installation is labor intensive and will require monitoring in order to ensure long term establishment.


OPERATIONS AND MAINTENANCE CONSIDERATIONS:

  • In early years of installation, the eelgrass will require maintenance and monitoring, but once it is established, it will be self-sustaining.



Other Types of Aquatic Habitat:
Click the images and links below to explore other types of Aquatic Habitat.


Tide Pool UnitsNearshore Reef



Floating Wetlands



Head back to the Measures Explorer to check out other flood and seismic measures.


Measure under the Aquatic Habitat measures related to ecological infrastructure opportunities to address flood risk

Looking for more? Head back to the Measures Explorer to check out other flood and seismic measures.


Eelgrass bed in New England ©Cornell Cooperative Extension Marine Program
DESCRIPTION:
Eelgrass is a flowering underwater plant that exists completely submerged. Growth of eelgrass improves water quality as well as transparency by trapping and storing particles and dissolved nutrients. Eelgrass growth can result in wave attenuation, bottom stabilization and habitat creation.





ECOLOGICAL INFRASTRUCTURE:
WATER LEVEL RANGE: Intertidal to subtidal

SHORELINE LOCATION:
In Water




DESIGN LIFE:
ADAPTABILITY:
IMPACT ON THE WATERFRONT:
CONSTRUCTION COST:
N/A
High
Minor Intervention
TBD




COASTAL FLOOD HAZARDS MITIGATED:
Enhancements can provide flood protection when combined with other physical infrastructure





Sea Level Rise
Storm Surge
Groundwater
Waves
Erosion




MEASURES COMPATIBILITY:
ECOSYSTEM SERVICES: Measure may affect these shoreline values






Flood
Seismic
Vegetated Terraces, Revetments, Levees
N/A
Aquatic Habitat
Terrestrial Habitat
Water Quality
Carbon Storage




CONSIDERATIONS:

ADVANTAGES:

DISADVANTAGES:





  • Eelgrass beds provide a number of ecological benefits but require considerable labor and time to install and monitor.
  • Feasible sites have soft substrates, low wave energy, shallow elevation, and suitable water quality (salinity, turbidity).
  • Migration pathways for eelgrass beds should be considered in anticipation of sea level rise.

  • Eelgrasses provide wave attenuation and bottom stabilization with no additional installation of infrastructure.
  • Increase biodiversity and provides marine habitat.

  • Potentially significant construction cost.
  • Potential long-term monitoring.




CONSTRUCTION IMPACTS TO THE PUBLIC:

SEA LEVEL RISE ADAPTATION OPPORTUNITIES:

CASE STUDIES:





  • Feasible locations are generally distanced from marine traffic. Because installation and monitoring would likely occur outside of marine traffic areas and from the water, construction impacts to the public would likely be negligible.

  • Adaptable to water levels. Will migrate as water levels change if an adequate migration pathway is present.

  • None cited




DESIGN OPPORTUNITIES:





Ecological Enhancements

Urban Design

Form
  • Measure is an ecological enhancement.

  • Eelgrass beds can attract recreational water users seeking to view wildlife.

  • Form is subject to environmental conditions, and largely invisible to the public.




DESIGN CONSIDERATIONS:

  • Eelgrass will require certain design considerations to be successful, including focus on performance factors such as waves, currents, tides, turbidity, water quality, and salinity conditions.


SITE-SPECIFIC CONSIDERATIONS:

  • Water levels, waves, and currents should be well defined. Eelgrasses prefer shallow waters and low energy wave environments.
  • Eelgrass requires a soft substrate (fine gravel, sand, mud) to root.


INSTALLATION AND CONSTRUCTABILITY CONSIDERATIONS:

  • Initial installation is labor intensive and will require monitoring in order to ensure long term establishment.


OPERATIONS AND MAINTENANCE CONSIDERATIONS:

  • In early years of installation, the eelgrass will require maintenance and monitoring, but once it is established, it will be self-sustaining.



Other Types of Aquatic Habitat:
Click the images and links below to explore other types of Aquatic Habitat.


Tide Pool UnitsNearshore Reef



Floating Wetlands



Head back to the Measures Explorer to check out other flood and seismic measures.


  • Thank you for learning about ways to strengthen the waterfront through the Measures Explorer! Please share your feedback on the Eelgrass Restoration measure.

    Would you like to see it prioritized as a potential solution along San Francisco's waterfront? Do you have any concerns or input you would like to share about this measure?

    The Port wants to hear from you!

    Share Feedback
Page last updated: 04 September 2020, 13:41