About half of the 351 municipalities in the Commonwealth currently have their own wetlands protection bylaw or ordinance (collectively, “bylaw”), which is administered by the city’s or town’s conservation commission in conjunction with the state Wetlands Protection Act (the “WPA”).

Some of these communities already have provisions that address climate change. Others are contemplating amending their existing bylaws and regulations to do so. Still others, like the City of Boston, are considering adopting for the first time a local wetland permitting program.

Wetland resource areas, already regulated to protect their ability to mitigate flooding and storm damage as well as to protect surface and groundwater quality, are naturally poised to help mitigate the similar effects of climate change on a community. To preserve these functions, municipalities are placing a greater emphasis on regulating work in or near wetland resource areas, such as marshes, vegetated wetlands, floodplains, beaches, banks, dunes, rivers, streams, lakes, and ponds.

A municipality can adopt a wetland bylaw under its Home Rule authority as long as the provisions are more stringent than the WPA. Being more stringent might include protecting additional interests, or functions, beyond the eight protected by the WPA, such as protection of wildlife, natural scenic beauty, or recreation. It also might mean regulating a greater geographic area than the Act, such as isolated (not just bordering) vegetated wetlands, areas within 100 feet of water bodies, or vernal pools (even if outside a vegetated wetland). It also might mean having stricter requirements (or “performance standards”) such as a mitigation ratio of greater than the 1:1 generally required in the WPA and MassDEP’s implementing Wetland Regulations (310 CMR 10.00).

These are but a few of the myriad of ways a wetland bylaw and the regulations promulgated thereunder can be more stringent than the WPA and its regulations.

With sea level rise being one of the most commonly discussed impacts of climate change, it is not surprising that several coastal towns have provisions in their wetlands bylaws to consider this during project review.

For instance, Duxbury requires the design and construction of projects in the FEMA- designated “A-zone” portion of the 100-year floodplain to take into account sea level rise at a rate of 2.8 feet per 100 years. Hingham has a similar requirement, but also applies it to projects proposed in the velocity zone (“V-zone”). Hingham specifies that a rate of 1 foot per 100 years “or other credible evidence” such as from the Intergovernmental Panel on Climate Change be used. Falmouth has one rate (“at least” 1 foot per 100 years) for work in AE-zones and a higher rate (“at least” 2 feet per 100 years) for work in the VE-zone.

As sea levels rise, coastal wetland resource areas are predicted to shift landward. Scituate requires landward migration of resource areas in response to sea level rise to be incorporated into the design and construction of structures proposed in the coastal floodplain. The lowest floor of a structure in a FEMA-mapped AE-zone must be at least 1 foot above the base elevation, and the lowest horizontal structural element must be at least 2 feet above the base flood elevation – unless a higher elevation is determined by the Commission. Falmouth says that any activity within the 10-year floodplain cannot have an adverse effect by impeding the landward migration of other resource areas within this sub-area of the floodplain.

Recognizing that FEMA’s 100-year floodplain mapping can be inaccurate or outdated, many coastal communities allow the coastal floodplain, usually called Land Subject to Coastal Storm Flowage (“LSCSF”), to be defined by the FEMA maps, surge of record, or flood of record, whichever is greater. Similarly, recognizing that coastal bank function as a barrier to coastal storm flooding, some communities define the top of coastal bank at a higher point than MassDEP would under the WPA.

Inland communities are also using their wetland permitting programs to build climate change resiliency. The Arlington Conservation Commission recently added to its wetland regulations a new “Climate Change Resilience” section which requires an applicant, “to the extent practicable and applicable as determined solely by the Commission, integrate considerations of adaptation planning into their project to promote climate change resilience so as to protect and promote resource area values into the future.”

An applicant must address in a narrative: 1. Design considerations to limit storm and flood damage from extreme weather events; 2. Storm water surface runoff mitigation and reduction of impervious surfaces; 3. Vegetation planting plans to improve climate change resiliency; and 4. Protection of proposed structures to minimize damage from potential climate change impacts. With the introduction of new terms, the Commission added the definitions to its regulations, such as “adaptation”, “extreme weather event”, “impacts of climate change”, and “resilience.”

Many eyes are now on the City of Boston as it considers enacting its first wetland protection ordinance. Entitled, “Ordinance Protecting Local Wetlands and Promoting Climate Change Adaptation in the City of Boston”, the proposed draft explicitly and comprehensively integrates climate change resiliency measures into a local wetland permitting program. The current draft draws on approaches and definitions of other communities and expands on them. For instance, LSCSF is defined not as the more common FEMA 100-year floodplain, but the FEMA 500-year floodplain. “Special Transition Areas” landward of salt marsh, barrier beaches and coastal dunes are created to allow transition of those areas landward, so must be kept in a natural state as much as possible. Stormwater calculations must be based on “best available measures of precipitation” frequency. Also, the Conservation Commission is directed to consider eight factors when considering a project’s adaptation to potential climate change impacts.

In conclusion, Massachusetts cities and towns are not waiting for the state or federal governments to begin enacting laws to help build climate change resilience in their communities, but are turning to their own wetland regulations.