Create or amend local wetland bylaws: Account for projected sea level rise

Adaptation Strategies and Actions

Create or amend local wetland bylaws: Account for projected sea level rise

Adaptation type:

Planning and prioritization

Policy, laws, and regulations

Strategy:

Update or create local bylaws that incorporate climate change impacts

Action

Update or create town wetlands bylaws to consider projected sea level rise

Wetlands bylaws
In Massachusetts, town conservation commissions are charged with protecting local wetland resources. Commissions regulate wetlands using the Massachusetts Wetlands Protection Act, but can also enact their own wetlands bylaws to further protect wetland resources. Wetland bylaws and any amendments must be approved at public town meetings.

These bylaws can further restrict activities deemed to have significant impact on wetland values including the following resources and functions:

public or private water supply;
aquifer and groundwater^? protection;
flooding and storm damage;
erosion, sedimentation control, and prevention of water pollution;
the protection of fisheries, shellfish and wildlife;
biodiversity; and
recreation

How to make your wetlands bylaw proactive to climate change
Local wetland bylaws present an opportunity to adaptively consider climate change impacts in the management of wetland, coastal and other water resources. To make a wetlands bylaw more proactive to coastal inundation, storms, and flooding in a changing climate, a community should consider projected sea level rise when placing restrictions on development activities in areas of special flood hazard. For example, many communities delineate and regulate lands subject to inundation by coastal storms and floods. These are often based on the historical rate of sea level rise for a particular location or 100-year flood zones. Communities could more proactively manage their coastal resources under climate change by updating their bylaw to include a specific projection for sea level rise under future climate change, thereby increasing the restricted area where development is not to be permitted due to flood hazard and impact on important lands for flood control. Similarly, communities could include language stating that the community is allowed to consider climate change and future sea level rise projections in determining lands subject to flooding.

In Hingham, MA, where the local wetland bylaw restricts activities deemed detrimental in certain zones that are subject to inundation and flooding, recent changes to the bylaw allow the commission to consider the potential impact of sea level rise when approving activities:

“For activities proposed in VE-zones and A-zones, at a minimum, the historic rate of relative sea level rise in Massachusetts of 1 foot per 100 years shall be incorporated into the project design and construction. The commission may also take other credible evidence of projected sea level rise, such as the Intergovernmental Panel on Climate Change into consideration.”

The change is small, but it now allows the Conservation Commission to use better information as it becomes available to more accurately predict the impact of sea level rise and regulate activities in lands vulnerable to flooding.

Changes to the bylaw would be developed by the town conservation commission and need to be approved at a town meeting. The town would have to already have a wetlands protection bylaw in place, or would first have to get one passed at a town meeting.

The Massachusetts Association of Conservation Commissions has a model bylaw² that towns can use as a starting place: http://maccweb.org/resources_bylaws.html. However, the model currently does not yet include explicit considerations for climate change impacts, such as sea level rise.