HomeMy WebLinkAboutCons_Comm_Presentation_8-15-24_CJG1
08/15/2024
Great Island Homeowners
Association – NOI for Dune
Restoration and
Maintenance Along Great
Island Road
Dec. 18, 2023 Storm Damage
Areas of Significant Damage:
•810 ft area NE of ‘S’ curve
•110 ft area SW of ‘S’ curve
Concerns:
•Loss of vehicle access to island
•Year-round residents that require
access to/from island
•Loss of access by emergency
services (fire and EMS)
•Forecast for 2 more significant
storm events in January
Emergency Certification Issued Jan. 5, 2024
Emergency Certification Allowed:
•Installation of 350 sandbags at
1 cy each
•Sand fill behind, on top and in
front of bags to create a dune
width and slope like pre-existing
conditions
•Bags to be joined together and
monitored for
damage/displacement
•Any displaced bags to be
retrieved
•Woods Hole Group and Fuss &
O’Neill to oversee installation
Emergency Work
•Bags installed Jan. 8-12
•Sand cover placed Feb. 6-8
•NOI filed Apr. 11
810 ft
110 ft
Impacts to Wetland Resources
•Coastal Dune – sandbags
•Coastal Beach – construction
access only
•Barrier Beach
•Estimated Habitats of Rare
Wildlife – NHESP issued no
“take” letter, recommended
TOY
•Land Subject to Coastal
Storm Flowage Area Shoreline
Length (ft)
Coastal Dune
(sq ft)
Coastal Beach
(sq ft)
Barrier Beach,
Rare Species
Habitat, LSCSF
(sq ft)*
North 810 24,231 12,363 40,254
South 110 2,031 2,047 6,518
TOTAL 920 26,262 14,410 46,772
* Includes staging areas on west side of Great Island Road
Alternatives Considered
Do Nothing
•Risk of road damage & loss of
vehicle access
Dune Nourishment
•Potential for loss of nourishment
material with upcoming storms
•Continued risk of road damage
•Potential need for repeated
nourishment
•Impacts from truck traffic
Geotextile Bags with Sand Cover
•Protects road from damage &
undermining
•Geotextile bags readily available
(biodegradable materials were
not available at the time)
•Minimizes impacts associated
with repeated nourishment
(trucking and continual sediment
transport into coastal system)
Recommended Conditions
1.Monitor sandbags monthly with report/photos to Conservation Commission.
2.Inspect sandbags following storms with report/photos to Conservation Commission within
2 days following storm.
3.Keep sandbags covered with sand with up to 2,090 cy of beach compatible sand twice
annually.
4.Notify Conservation Commission in advance of nourishment activity and follow up with
report to Commission.
5.Nourishment to occur before March 1 and after August 31.
6.If bags become damaged, they will be removed immediately to prevent loss of geotextile
fabric into the coastal environment.
7.Replacement of existing sandbags with new geotextile bags is not allowed.
GIHA Plans for Maintaining Access to Island
Short-Range Plan (1-5 years)
Protects against erosion while intermediate- to long-range plan is implemented
•- Seek an Order of Conditions proactively for installation of biodegradable fiber
rolls/envelopes in new areas of vulnerability, as needed
Intermediate- to Long-Range Plan (3-50 years)
Protects against high tide flooding through 2050/2070, protects against ‘low energy’ storm
related flooding/erosion through 2050.
•- Raise sections of road
•- Retreat sections of road
•- Replace Bridge