Post planting inspections conducted byAECOM divers documented emigration ofrock crab spp., sea star spp., and algae spp.(clockwise from top left)

Average number of eelgrass shoots (and

quadrat from diver inspections

Harvesting healthy eelgrass shoots from Niles Beach (left), counting, sorting (middle), and preparing fortransplantation efforts (right).

2007 and 2008 planting plots (left), schematic of 1/4m² quadrats within plots (top), and PVC frame used toorient restoration efforts (bottom)

Bundle of eelgrass shoots withhealthy rhizome

Gloucester Harbor eelgrass habitat including Niles Beach(donor bed), Stage Fort (reference bed), and Pavilion Beach(impacted area).

Existing eelgrass beds at Pavilionbeach prior to construction

In 2005, the United States Environmental Protection Agency and theMassachusetts Department of Environmental Protection mandated theCity of Gloucester, MA to implement Combined Sewer Outfall controls. TheWashington Street Drain and Outfall Project constructed at Pavilion Beachin Gloucester was completed in 2007. As outlined in the permit applicationsfor the project, the installation of the Washington Street Drain was planned toresult in temporary impacts to approximately 23,800 square feet (2,213 squaremeters) of eelgrass () habitat.

To mitigate for thesetemporary impacts, eelgrasshabitat was proposed tobe restored in place afterinstallation of the pipeline.Although temporary impactsto eelgrass were permitted,the mitigation plan wasintended to facilitate therestoration of eelgrassfunctions and values alongthe impacted work corridor.The mitigation plan included

sediment over rip-rap aswell as replanting eelgrassthroughout the entire corridorto restore the habitat to itsoriginal pre-constructioncondition. In addition, theplan included mitigation forthe 0.62 acre eelgrass areasurrounding the corridorwhich was unintentionallydisturbed during construction activities. Priorto full-scale harvesting and transplanting, a testplanting was performed in July 2007 to evaluateif the chosen methods were appropriate.In September 2008, full-scale planting wasconducted within the construction corridor aswell as the areas which were unintentionallyaffected by construction. In 2007 and 2008,approximately 32,800 individual eelgrass shootswere planted in 27 plots.

Project GoalsRestore value and function of eelgrass habitat located at Pavilion Beach to pre-construction condition

Eelgrass Restoration: Using SCUBA to Restore EelgrassBeds and Preserve Critical Coastal Habitat Nathan Henderson

(1), Jennifer Doyle-Breen

(1)

(1) AECOM- 701 Edgewater Drive, Wakefield MA 01880(2) City of Gloucester, Gloucester MA 01930

Project BackgroundPreliminary Restoration Success Eelgrass Transplantation

HarvestingHealthy eelgrass shoots were harvested by divers from Niles Beachdonor bed using the individual rhizome collection methodology (Davisand Short 1997)Harvested eelgrass rhizomes were sorted and bundled at the surface.Shoots were transported to Pavilion Beach and stored in ambientseawater

Preliminary results2 Week Test Plot Inspection

68% survival rateUnaccounted for shoots appearedto be missing rather than dead ordecaying

the base of planted shoots14 Month Test Plot Inspection

102% survival rate Five quadrats had <50 shoots Six quadrats experienced growth of >40 shoots outside the originalquadratOrange sponges on sporadic leaf blades throughout the plot

One Month Full Scale Inspection70% survival rate

The Stage Fort reference area had an average of 38 shoots per quadratThe success criteria (Short et al. 2000) for the reference bed was 52The one month success ratio (Short et al. 2000) was 90

Biota RecolonizationPseudopleuronectes americana), Cunner

(Tautogolabrus adsperus), Sea Raven (Hemitripterus americanus)Homarus americanus), Rock crab (Cancer irroratus)

Hermit crab (Pagurus spp.)Mollusks- Moon snail (Lunatia heros)Echinoderms- Sea star (Asterias spp.)Algae, sponges and other aquatic plants

Future Monitoring and Long Term Success EvaluationShoot count, biomass, and canopyheight comparison with referencearea (Short et al. 2000)Qualitative assessment ofrecolonization by marine biota

Conclusions to DateHigh survivability and observedspread of 2007 test plot suggestsmethods are effectiveShort-term survivorship of full scaleplanted plots similar to 2007 testplot suggest successful restorationfor entire construction corridorBiota recolonization providesevidence for successful restorationof Essential Fish HabitatPotential causes for shoot loss

Uprooting as a result of weather eventsAlgal, tunicate, and/or sponge growthHerbivory

ReferencesDavis, R.C. and F.T. Short. 1997. Restoring eelgrass, Zostera marina L., habitat using a new transplanting

technique: The horizontal rhizome method. Aquatic Botany 59 (1997) 1-15.Short, F.T., D.M. Burdick, C.A. Short, R.C. Davis, and P.A. Morgan. 2000. Developing success criteria for

AcknowledgementsField assistance was provided by US EPA, MA DMF and RDA Construction –this assistance was critical to the project success. The City of Gloucester,MA funded the restoration work as part of the mitigation program for theWashington Street Drain Outfall.

MonitoringShort-term survivability of transplanted eelgrass shoots was inspected bydivers on the 2007 test plot two weeks following planting, and on the shootsplanted in 2008 one month following planting. The test plot was inspected 14months following planting activities to evaluate any trend towards eelgrassbed expansion. Inspections consisted of counting the number of live eelgrassshoots present in 10 to 12 randomly selected quadrats at the impacted areaand comparing to similar inspections at the Stage Fort reference site.

PlantingDivers planted 10 bundles of 5 eelgrass shoots within the perimeter ofeach ¼ m2 PVC quadrat24 quadrats in each plot were planted27 plots (3m X 4m) were planted using the following methodology:

dig a small pit and placing 5 rhizome ends in the bottomanchor rhizomes in substrate using a bamboo skewer

were planted