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HomeMy WebLinkAboutGIHA_NOI_Project_Description_Revised_9-12-2024 Woods Hole Group, Inc. • A CLS Company _____________________________________________________________________________________________ Great Island Homeowners Association – Notice of Intent Application Page B1 of B11 Sections of Great Island Road, Yarmouth, MA B. PROJECT DESCRIPTION – REVISED SEPT. 12, 2024 Introduction Great Island is a roughly 550-acre peninsula situated between the eastern shoreline of Lewis Bay and Nantucket Sound in West Yarmouth, Massachusetts. Great Island Homeowners’ Association (GIHA) includes 43 homes (and seven open lots) that are connected to the mainland by Great Island Road located on Great Island Barrier Beach. Great Island Road provides the only means of vehicle access for residents and has become increasingly vulnerable to coastal storm flooding and damage due to climate change. Figure B-1 shows the roadway network on Great Island. Figure B-1 Great Island roadway infrastructure (gray lines). The coastal beach and dune resources along the Nantucket Sound side of the road have lost width, elevation, and volume in recent years, creating a greater risk of erosion and coastal storm damage to the road. The vulnerability of the roadway, which serves as the only means of vehicle and emergency access to the Island, is a significant concern for GIHA. With a large enough storm, damage along Great Island Road could render the roadway impassable, with potential permanent damage to the road infrastructure, including the associated utilities (i.e., fiber-optic cable, electricity) that serve the Island. Damage to any of this infrastructure could threaten public health and safety for the Island’s year-round residents. The roadway's vulnerability was exposed on December 18, 2023, when a coastal storm caused considerable damage to the beach, dune, and roadway, resulting in a severely degraded dune and over washed sand and debris in the road. During that storm, which included strong southeast winds and significant waves in Nantucket Sound, there was extensive damage to two (2) portions Woods Hole Group, Inc. • A CLS Company _____________________________________________________________________________________________ Great Island Homeowners Association – Notice of Intent Application Page B2 of B11 Sections of Great Island Road, Yarmouth, MA of the primary frontal dune protecting the south side of Great Island Road. The areas that sustained the greatest damage are indicated by the red lines, with dune photos in Figure B-2. Figure B-2 Areas of coastal dune damaged along Great Island Road during the December 18, 2023 storm. During the fall of 2023, the GIHA retained Woods Hole Group, in collaboration with Fuss & O’Neill, to conduct a vulnerability and alternatives assessment of Great Island's roadway and bridge infrastructure with the goal of developing long-term solution(s) for maintaining access to Great Island. Since the Woods Hole Group and Fuss & O’Neill team were already working on assessing the long-term resiliency of the roadway, GIHA requested that the team respond to the December 2023 storm damage with alternatives for maintaining road access. Woods Hole Group visited the site with the Town of Yarmouth's Fire Captain, Kevin Huck, on December 26 to assess public health and safety issues associated with the existing roadway. Captain Huck expressed concerns about the ability of emergency responders to reach the Island if further damage to the roadway were to occur. With two additional Sou’easters on the radar for early January, GIHA understood the need for emergency intervention to prevent the roadway from eroding. On GIHA's behalf, Woods Hole Group requested Emergency Certification to restore the primary dune and protect road access. The Emergency Certification was issued under 310 CMR 10.06 on January 5, 2024 (see Section E), and work on the project was completed on February 9, 2024. As required by the regulations, this Notice of Intent is being filed after the fact for work completed under the Emergency Certification. Project Description The emergency dune restoration activities along Great Island Road, took place over 910 linear feet of shoreline that were the most significantly damaged during the December 2023 storm. The Woods Hole Group, Inc. • A CLS Company _____________________________________________________________________________________________ Great Island Homeowners Association – Notice of Intent Application Page B3 of B11 Sections of Great Island Road, Yarmouth, MA dune restoration activities were completed in two phases. The first phase involved the installation of geotextile bags filled with sand in the areas where the primary coastal dune was significantly compromised and where the road needed protection against future storm damage. The second phase involved placing sand cover over the bags and creating a natural slope in front to mimic the dune function and aesthetics. Construction occurred along two distinct stretches of shoreline, as shown in Figure B-3. Work occurred over 810 linear feet to the north, and 110 linear feet to the south. Figure B-3 Reaches of shoreline where emergency dune repair occurred in yellow. Phase I Bulk Bag Placement – January 8th - 12th, 2024: During this first phase of work, bulk bags were filled with imported clean, compatible sand and placed along the line of the coastal dune. Then, they were backfilled with additional sand behind the bags to fill in gaps with the remaining eroded dune. Each bulk bag is made of woven coated polypropylene, measuring 35-in x 35-in x 45-in and holding approximately 1.2 cubic yards of sand that weighs over a ton. Along the northern stretch of the dune, the bulk bag footprint encompasses 2,400 square feet, made up of 213 bulk bags, along 810 linear feet of coastal dune. The bulk bag footprint encompasses 262.5 square feet in the southern area of the dune, including 24 bulk bags placed along 110 linear feet of shoreline (Figure B-4). In total, 237 bulk bags were installed, requiring approximately 280 cubic yards of sand. An additional 362 cubic yards of sand was placed behind the bulk bags in the north area as backfill. Approximately 642 cubic yards of sand were imported and put in the Project area during this phase of this work. Woods Hole Group, Inc. • A CLS Company _____________________________________________________________________________________________ Great Island Homeowners Association – Notice of Intent Application Page B4 of B11 Sections of Great Island Road, Yarmouth, MA Figure B-4 Bulk bag placement to the south along the edge of Great Island Road in place of dune damaged during the December 2023 storm (April 1, 2024). Phase II Sand Cover Placement – February 6th - 8th: During this second phase of work, the bulk bags were covered with compatible, clean sand that mimicked the existing natural dune function and aesthetic. This sand cover was also placed to help prevent the bulk bags' accelerated deterioration from UV light. The sand was placed roughly one foot over the top of the bulk bags, and then the front slope of the cover was graded on a 4H:1V slope from the top to the toe. Each end of the sand cover was feathered into the existing coastal dune to provide a smooth transition to reduce erosion. Along the southern stretch of bulk bags, sand was placed and graded only on top and in front since the bags are flush against the road, and additional sand on the back side of the bags would interfere with vehicle passage. Snow fencing was placed along the backside of these bulk bags to stabilize the sand, protect the bags from UV degradation, and improve the road's aesthetics. A total of 1,447 cubic yards of sand was placed over the north and south bulk bag arrays. The northern nourishment encompassed an area of 24,231 square feet and the southern nourishment encompassed a total area of 2,031 square feet. Woods Hole Group, Inc. • A CLS Company _____________________________________________________________________________________________ Great Island Homeowners Association – Notice of Intent Application Page B5 of B11 Sections of Great Island Road, Yarmouth, MA Figure B-5 Final grading of sand cover in the northern construction area at a 4H:1V slope facing west (April 1, 2024). Construction Methods: Each bulk bag was filled using a skid steer to hold the bags open by the lifting loops, and then a mini-excavator filled each bulk bag with sand. Once filled, the skid steers maneuvered to the placement location and lowered the bulk bags onto the dune. Bulk bags were placed in a tight single row aligned to follow the core of the degraded dune. Each bulk bag was tied shut to prevent future sand loss. The bulk bags were then tied together in groups of 10 using a line to enhance stability and reduce the chance of damage or failure during future storms. Once a section of bags was complete, a sand cover was placed behind the bags to fill the void between the bags and the edge of the road. During Phase II of construction, sand was delivered by a tri-axle truck and staged in existing sandy vehicle turn-around areas on the west side of Great Island Road. Three materials storage areas were used for the northern area, and two storage areas were used for the southern area, encompassing a total of 6,100 square feet. A front-end loader was then used to move the sand to the dune using temporary access paths across the bulk bag arrays. A skid steer was then placed and graded the material across the dune. Access to the dune restoration area for the skid steer was from the coastal beach, directly seaward of the bags. The sand was placed to a depth of roughly a foot over the top of the bulk bags, and then the front slope of the cover was graded on a 4H:1V slope from the top of the bags to the toe of the dune. Each end of the sand cover was feathered into the existing coastal dune to provide a smooth transition to reduce erosion (Figure B-6). Woods Hole Group, Inc. • A CLS Company _____________________________________________________________________________________________ Great Island Homeowners Association – Notice of Intent Application Page B6 of B11 Sections of Great Island Road, Yarmouth, MA Figure B-6 Shows Sand placement along the edge of Great Island Road, where a skid steer was used to grade sand along the top and sides of the bulk bag array (February 8, 2024). Figures B-7 and B-8 show the temporary dune access points, the limit of construction access on the Coastal Beach, and the pre-existing vehicle turnaround areas used for construction access and sand staging. Figure B-7 Construction access and staging areas used for work in the northern area. Woods Hole Group, Inc. • A CLS Company _____________________________________________________________________________________________ Great Island Homeowners Association – Notice of Intent Application Page B7 of B11 Sections of Great Island Road, Yarmouth, MA Figure B-8 Construction access and staging areas used for work in the southern area. Wetland Resources Impacted: Work for the project occurred within Coastal Dune, Coastal Beach, Barrier Beach, Estimated Habitats of Rare Wildlife, and Land Subject to Coastal Storm Flowage resources. Table B-1 describes the total area of disturbance to each resource as a result of the Project construction. Table B-1 Project’s Total Area of Disturbance. Area Shoreline Length (L.F.) Primary Coastal Dune (S.F.) Coastal Beach (S.F.) Barrier Beach, Rare Wildlife Habitat, & Land Subject to Coastal Storm Flowage (S.F.) * North 810 24,231 12,363 40,254 South 110 2,031 2,047 6,518 Total 920 26,262 14,410 46,772 * Total areas include staging areas on the west side of Great Island Road. Ongoing Maintenance: The bulk bags with sand cover are intended to be a temporary erosion control measure to prevent damage to the roadway and underlying electric utilities until the results of the alternatives analysis for long-term resiliency have been completed. The study is scheduled for completion in September 2024. The adaptations identified in the study would then be designed and permitted and ready for construction in approximately two to five years. Consequently, the emergency roadway protection will serve as temporary erosion control for approximately two to five years while different adaptations are selected, designed, permitted, and constructed. During this time, additional sand cover over the roadway protection is being requested up to 2 times per year to help maintain the longevity of the erosion control solutions and suitable slopes for protected shorebirds. Maintenance may include nourishment of up to 2,090 cubic yards of Woods Hole Group, Inc. • A CLS Company _____________________________________________________________________________________________ Great Island Homeowners Association – Notice of Intent Application Page B8 of B11 Sections of Great Island Road, Yarmouth, MA beach-compatible sand on a bi-annual basis (nourishment amount is based on the total amount used to complete Phases I and II of the existing Project) to maintain the current dune profile. Alternatives Considered: Do Nothing The December 18, 2023, storm caused significant erosion of the Coastal Dune within several feet of the roadway. The Do Nothing alternative would leave the dune and road infrastructure as is, with no changes to improve the dune's protective value. The Do Nothing alternative would risk complete erosion of the Coastal Dune with future storm activity and likely damage to the roadway and associated utilities that serve the 43 developed properties on Great Island. This alternative has the potential to cause significant damage to the roadway and possibly trap year-round residents on the island if they are not evacuated in advance of an impending storm and renders emergency access by land impossible. Storm damage to the roadway could also result in pieces of asphalt dislodging and spreading across the beach. For these reasons, this alternative was eliminated from further consideration. Dune Nourishment Dune nourishment was also considered an alternative for restoring the dunes to their pre-storm condition and footprint. Following the December 18, 2023 storm, it was estimated that restoration of the primary Coastal Dune would require 3,000 cubic yards of sediment. The viability of this alternative was questioned when it was determined that storms of a similar track and magnitude would likely continue for weeks following the December 18, 2023 storm. It was determined that any dune nourishment efforts would have only short-term effects, and the likelihood of damage to the roadway and associated utilities would remain high with this alternative. Repeated renourishment during the winter storm season would introduce significant quantities of sediment to the littoral system at a high cost to the GIHA. For these reasons, this alternative was eliminated from further consideration. Bulk Bags with Sand Cover This alternative includes the use of bulk bags with sand cover along the most severely eroded sections of the dune to protect vulnerable sections of Great Island Road. As seen in Figure B-9, this alternative proposes placing the bulk bags covered with nourishment, including backfill, to replicate the previous dune profile. The sand cover protects the bags from UV degradation and creates dune slopes suitable for protected shorebirds. The bulk bags also provide a buffer along the edge of the roadway that prevents wave action from further damaging the road and associated utilities. By maintaining sand cover over the bags with up to 2,090 cubic yards of material twice per year (as needed), this alternative will continue to provide a sediment source to the adjacent beaches and will maintain the dune profile that existed naturally on this stretch of shoreline prior to the winter storm season of 2023/2024. This alternative was identified as the best opportunity to protect the roadway from further erosion due to its increased vulnerability after the December 2023 damage. However, this alternative is seen as a temporary solution until Woods Hole Group, Inc. • A CLS Company _____________________________________________________________________________________________ Great Island Homeowners Association – Notice of Intent Application Page B9 of B11 Sections of Great Island Road, Yarmouth, MA the study for a longer-term solution(s) for access to Great Island can be identified, designed, permitted, and implemented. It is estimated that this temporary solution will need to be in place and maintained for approximately two years until the longer-term solution(s) are ready for implementation. Figure B-8 Bulk bags with sand cover which was selected as the best alternative for the emergency response at Great Island. Proposed Alterations to Emergency Bulk Bag Installation: Because of concerns voiced by the Conservation Commission regarding use of geotextile materials and loss of sand cover over some of the geotextile bags, a modified design for roadway protection has been developed for the southern section of the project site. The design includes biodegradable fiber rolls with a sand cover and beach grass plantings. The existing geotextile bags will be removed from the southern section of the site and replaced with an array of four (4) 24-inch diameter fiber rolls as shown on Sheet 3 of 3 of the plans entitled “Revised Design for Roadway Protection and Rebuilding of Primary Coastal Dune Along South Area at Great Island Road, West Yarmouth, MA”, dated 9-12-2024. The crest elevation of the fiber rolls will be set at the same elevation as the road and the rolls will be anchored in place using steel cables and duckbill anchors. Beach and dune compatible sediment will be used to restore a dune over the fiber roll array and beach grass will be planted 12 inches on center across the restored dune. The construction process will include removing the existing geotextile bags and stockpiling the sand on the upper part of the beach for use during the dune restoration. A front-end loader or mini excavator will be used to prepare the area along the edge of the road so that the fiber rolls can be installed at the design elevation. The steel cables will be looped around the fiber rolls and attached to duckbill anchors. The anchors will be driven to a depth of 10 ft to ensure that the fiber rolls will remain in place as protection for the road. Stockpiled sediment taken from the Woods Hole Group, Inc. • A CLS Company _____________________________________________________________________________________________ Great Island Homeowners Association – Notice of Intent Application Page B10 of B11 Sections of Great Island Road, Yarmouth, MA geotextile bags will then be used to cover the fiber roll array, essentially restoring the dune that existed prior to the December 2023 storm. Beach grass will then be planted across the restored dune area. The beach grass plantings will include 2-3 culms per hole, planted 12 inches on center. The construction access and staging areas will essentially be the same as used during installation of the geotextile bags in January 2024 (Figure B-8). Both sections of emergency roadway protection will be monitored in the early spring and fall for as long as they are in place. The geotextile bags (north section) and fiber rolls (south section) will be examined for damage and/or displacement. Should sections of the geotextile bags show signs of damage or deterioration, they will be replaced with biodegradable fiber rolls as designed for the south section. The monitoring will also include evaluation of sand cover to minimize degradation of the geotextile bags and fiber rolls due to UV exposure. If necessary, additional sand cover over the fiber rolls and bags will be installed up to 2 times per year using up to 2,090 cubic yards of beach-compatible sand on a bi-annual basis. Keeping the fiber rolls and bags covered with sand will help to maintain the longevity of the roadway protection and ensure suitable slopes for protected shorebirds. Proposed Beneficial Reuse of Sweetheart Creek Dredged Materials: GIHA is proposing to beneficially reuse sediment dredged from Sweetheart Creek during the Fall 2024 for sand cover on the north section (where needed) and new south section fiber roll roadway protection. The sediment will be trucked to the placement sites following the Sweetheart Creek dredge permits and placed over the roadway protection under this requested Order of Conditions. Response to MA DMF Comment Letter on NOI Dated April 24, 2024: The MA DMF comment letter indicates that the project area contains both eelgrass and horseshoe crab habitat. DMF also suggests that project work carried out under the Emergency Certification, including the ongoing sand cover required to keep the bags and fiber roll array covered, is similar to the larger Great Island Road Resiliency nourishment project that received a Superseding Order of Conditions on July 31, 2023. During permitting for the larger 77,000 cubic yard nourishment project, DMF recommended pre- and post-construction eelgrass monitoring to ensure protection of the resource. It is important to note that the current project proposes to place a small fraction of nourishment material (up to 4,180 cubic yards annually) as compared to the larger project. The material will also be constrained to the dune rather than lower on the beach as with the larger nourishment project. As such, there are few similarities between the two projects. DMF offered the following comments for the Commission to consider in issuing an Order of Conditions for the current project. Notes have been added in italics indicating whether the proposed project addresses the comments. Woods Hole Group, Inc. • A CLS Company _____________________________________________________________________________________________ Great Island Homeowners Association – Notice of Intent Application Page B11 of B11 Sections of Great Island Road, Yarmouth, MA • Time of year restriction for nourishment and beach construction activities between May 1 and June 31 of any year. The proposed project will adhere to this time of year restriction for all work on the beach. • Beach nourishment consistent with MassDEP’s Beach Nourishment Guide. The proposed project design is consistent the MassDEP’s Beach Nourishment Guide. • Planting and restoration plan for dune grass areas. The proposed project includes a planting plan for the restored dune areas. • Pre- and post-construction eelgrass monitoring plan. Due to the small scale of the proposed project and the minimum distance of 360 ft between the proposed work and existing eelgrass, adverse impacts to eelgrass resources are not expected. Pre- and post- construction monitoring of eelgrass is not warranted. • Modeling estimates of offshore migration and transport of nourishment material. Due to the small scale of the proposed project and the lack of impacts to offshore eelgrass resources, numerical modeling of cross-shore sediment transport is not warranted. • Construction equipment staged and operated upland of the intertidal habitat. The proposed project does not include use of construction equipment in the intertidal habitat. • Containment and clean up materials to be maintained onsite in the case of refueling onsite or refueling of equipment to occur offsite. Containment and clean up materials will be maintained onsite at all times.