Falmouth conservation meeting reviews new FEMA maps, state rules that will raise coastal building standards

Shannon Holst, a floodplain specialist with Barnstable County’s Cape Cod Cooperative Extension and WHOI Sea Grant, told the Falmouth Conservation Commission on Jan. 16 that changes to flood mapping and building codes will expand areas where the most stringent coastal construction standards apply. “Flood insurance rate maps, that’s what, the flood maps from FEMA are officially called,” Holst said, and added that “they do not incorporate sea level rise, or any changes in storms that we’re seeing.”

Holst said FEMA’s maps delineate the regulatory floodplain (the 1% annual‑chance area) but are “backwards looking,” and that state mapping and modeling that do include sea‑level rise are not yet regulatory. She said a new delineation—commonly called the limit of moderate wave action (LMWA) or “coastal A” zone—was added to some maps in 2017 and refined in 2021; where that coastal A zone exists, the state’s updated building code and proposed DEP (Massachusetts Department of Environmental Protection) performance standards would require V‑zone construction methods (open pilings, elevated utilities, no structural fill and restricted enclosures).

Why it matters: Holst and staff warned that the combination of the coastal A designation and a July 1 change in the Massachusetts State Building Code will mean more properties in Falmouth must be elevated on pilings, raise utilities above the mapped base flood elevation, and meet increased freeboard requirements. Holst said the building code raises freeboard requirements in some high‑risk areas from 2 feet to 3 feet and raises required utility elevations in A zones (previously 1 foot over mapped elevations) to 2 feet. For many coastal A areas she said, the practical effect is that structures must be built to V‑zone standards.

Details presented to the commission included: - FEMA flood insurance rate maps (FIRMs) were described as the regulatory baseline for federally backed mortgages and floodplain code provisions; Holst emphasized they are based on historical data and do not include sea‑level rise projections. - State mapping and the Massachusetts coastal flood‑risk model include sea‑level rise but are currently non‑regulatory; Holst recommended using both datasets for planning and said Falmouth’s GIS already contains the state layers. - The coastal A (LMWA) zone represents areas subject to moderate wave action (roughly 1½ to 3 feet) and, where present, will be treated under the new building code like velocity (V) zones for new or substantially improved structures. - V‑zone standards described include open‑pile foundations, elevation of utilities to the required design flood elevation, limitations on enclosed space under buildings (breakaway walls allowed but discouraged because they become storm debris), and a prohibition on structural fill to elevate building footprints within V zones. - The ‘‘substantially improved’’ threshold remains the standard test for imposing upgrades on existing buildings (generally a 50% threshold). Holst said the Cape Cod Extension recommends that towns adopt assessed value rather than applicant appraisal or market value to measure that threshold, to standardize decisions.

Commission discussion and local implications: Members and Town Building Commissioner Gary Street discussed implementation and short‑term permitting questions. Street said the town will need to enforce the new state building code when it becomes effective; panel members pressed for a GIS analysis of how much Falmouth acreage and how many parcels will newly fall into coastal A zones. Holst recommended that the commission and planning staff ask the town GIS team to quantify acreage and parcel counts so the town can gauge the scope of affected properties.

Commissioners raised practical local policy choices: several noted that building‑height limits mean required extra elevation can make homes appear taller or compressed; Holst suggested one municipal approach is to measure allowable height from the design flood elevation rather than the existing grade so buildings retain consistent proportions. The panel also discussed whether the existing 25‑foot setback from V zones could be replaced or supplemented by the LMWA line, which Holst said reflects the more current engineering and modeling.

Historic buildings: Holst explained that exemptions and special treatment exist for historic structures listed on the National Register or on certified local inventories; exemptions are narrow and applied case‑by‑case, and any relief must not negate the structure’s historic designation.

Regulatory outlook and next steps: Holst reviewed DEP’s pending performance‑standards proposals for land subject to coastal storm flowage, noting the draft included measures such as prohibiting new buildings in V zones, requiring elevation for substantially improved buildings and discouraging increases in impervious area or building footprint in hazardous coastal areas. She emphasized those DEP regulations are still pending and subject to change after public comment. The updated state building code becomes effective July 1; Holst and Town staff advised applicants that building to the new standard now can avoid having to retrofit later and may align better with lenders’ and insurers’ expectations.

Holst closed by demonstrating how to view maps at the FEMA Map Service Center (msc.fema.gov) and offered to work with town staff and planning boards on bylaw updates and GIS analyses. Street and several commissioners said they will consult with planning staff, the assessor’s office and local engineers to prepare for the code change and possible bylaw adjustments.

Ending: The commission did not take any formal votes at this session. Members were advised to expect further discussion on zoning/ wetlands bylaw changes, possible height‑measurement revisions measured from design flood elevation, and an updated list of affected parcels once the town’s GIS analysis is complete. Holst offered to follow up with staff and acknowledged some town boards on Cape Cod have already adopted stricter local standards.