Dennis Beach Committee hears Woods Hole study on Haggis Beach resilience

On Feb. 12, 2026, the Dennis Beach Committee heard a presentation from consultants with Woods Hole Group and EDR about damage to the Haggis Beach revetment and possible long‑term resilience options.

Adam Finkel, a coastal scientist with Woods Hole Group, said photos taken after the 2024 southwest storm events showed ‘‘4 to 6 foot waves’’ overtopping the structure and creating ‘‘really large voids, big enough to have a whole group of kids be able to crawl in there.’’ He said the town’s Department of Public Works performed emergency repairs to protect public safety, but the structure is approaching the end of its serviceable life and requires a planned solution.

The consultants described their scope — an existing‑conditions survey, resource‑area delineation, a coastal processes memo and conceptual alternatives — and summarized a coastal processes analysis that used historic aerials and shoreline data. Finkel reported line‑specific shoreline change rates on the Haggis Beach reach ranging from roughly 0.36 to 0.82 feet per year, with an average near 0.62 feet per year where erosion is active. He cautioned that revetments and groins can reduce apparent rates locally but cut off the dune as a sediment source.

Modeling using state flood‑risk guidance (MCFRM) showed mean high water and bands of storm conditions; consultants ran scenarios with and without the existing revetment. ‘‘If the revetment were removed or if the revetment failed, you’re looking at a loss of thirty‑forty feet of dune during a significant storm event,’’ Finkel said, adding that removing the structure at this location would be ‘‘poor engineering advice’’ because of likely flanking and loss to adjacent structures.

The team outlined upland and shoreline alternatives. Upland options include consolidating access to one primary path to protect dunes, adding a small picnic area and vendor pull‑off, improving ADA access with MobiMats and modest viewing platforms, and relocating a portable toilet. Shoreline options ranged from softer approaches (beach nourishment with sand envelopes or fiber rolls) to reconstructing an engineered revetment within the existing footprint or embedding the revetment in restored dune as a ‘‘Cadillac’’ option. Consultants emphasized trade‑offs: soft solutions on a higher‑energy shore require regular renourishment (they cited examples of roughly 1,100–1,300 cubic yards per placement in comparable projects), while engineered repairs can be costly but provide longer service life and may be permitable if paired with mitigation.

Consultants said they held a public meeting at a library last summer with nearly 60 attendees and heard a general preference for a lighter‑touch approach focused on safe access and modest increases in summer beach area rather than large upland redevelopment. Finkel said the team will issue a final report in the coming week that summarizes public feedback and refines alternatives, then present the findings at a joint public meeting with the Select Board.

Committee members asked about deliverables and cost. The consultants confirmed contract deliverables include the delineation, survey data, existing‑conditions plans and the coastal processes memo; alternatives remain conceptual until the town selects a preferred approach. On costs, the consultants said final construction estimates will require a preferred alternative, but noted opportunities to beneficially reuse existing rock and to pursue competitive grants and the town’s Beach Improvement Fund as potential match sources.

The presentation closed with consultants recommending continued public engagement and coordination with regulators; the next steps are publication of the final report and a joint Select Board meeting to review alternatives and receive public comment.