The train has left the station. Let’s keep our eyes on the destination.

By Tom Hopper and Ellen Marya, Center for Housing Data at MHP

In early 2021, then Governor Charlie Baker signed Section 3A of M.G.L. Chapter 40A into law (often referred to as just “3A,” or more colloquially, the “MBTA Communities Law”). This important zoning reform requires 177 municipalities in eastern Massachusetts to have at least one zoning district where multifamily housing is permitted by right. Following the law’s enactment, the state Executive Office of Livable Communities (EOHLC) formerly the Department of Housing and Community Development (DHCD) released guidelines for implementation. These guidelines set the requirements and rules for communities to achieve compliance. For those looking for a basic overview of the law, this video produced by MHP is a good place to start.

This research brief provides a snapshot of how far along the 177 MBTA Communities are on their path to compliance with Section 3A, aimed at providing a sense of how much momentum has already been built around these much-needed zoning changes. The brief will also introduce an analytical approach to evaluating potential development opportunities in approved 3A districts, and make the case for a coordinated, forward-looking approach to MBTA Communities rather than a reactive, defensive posture in response to a relatively small group of detractors.

Despite press coverage that highlights opposition and grandstanding by a few small groups, the MBTA Communities Law is moving ahead and working as intended.

The path toward compliance differs across municipalities subject to the law because each community is starting from a different point, but these general stages describe the process for most places:

Planning and analysis: In this stage, communities look at existing housing patterns and review prior planning efforts, such as a housing production plan, comprehensive plan, or sources of community input around development. Town planners, often with the assistance of a consultant, use these planning priorities to develop zoning alternatives to explore. Many come up with a range of options, perhaps choosing one or more locations and varying levels of dimensional requirements (e.g., building heights, parking requirements, rules determining lot coverage or setbacks from the property line, etc.). Using a compliance model developed by the state to measure zoning districts against program requirements, communities analyze which options will help them achieve their 3A obligations. Many municipalities begin engagement with community members even at this early stage in the process to keep the public informed about potential changes, explain the law and the complex set of requirements associated with it, and seek initial input on what community members hope to see in a district.

Pre-adoption review and community engagement: Once planners have determined they have a viable district plan, they are advised to submit a “pre-adoption review” application to the state and request feedback on their district within a 90-day window. This step allows communities to make sure they have run the compliance model correctly and understood the rules before they have voted and approved a district. Often simultaneously, and since this pre-adoption review can take time, communities expand their public engagement efforts at this time, aimed at building support and comprehension of the proposed zoning.

Adoption: Once a district has been proposed and the municipality feels confident that it will both be adopted and bring the community into compliance with 3A, the approving body will hold a vote to adopt the district. This process varies by form of government; the approving body could be participants at Town Meeting, or might be a city council, or another authorized decision-making body.

District compliance application: After a district is adopted, the municipality must assemble and submit an application to the state that includes detailed information and thorough analysis of the proposed zoning district. The municipality is deemed to be in official compliance with Section 3A only once the state has issued an affirmative compliance determination.

Implementation of the MBTA Communities Law began over a year ago, and every MBTA Community is somewhere in the above process. Millions of dollars in technical assistance have been deployed to connect municipalities with needed professional services and expertise, and most communities are diligently using these resources to move toward compliance. These efforts have not been as widely covered in the media as some of the critical points of view around the law, yet the law is already producing demonstrable results that deserve broader attention. While tracking is complex, the analysis below is our best estimate of where communities are in the planning and compliance process as of March.

35 communities have passed multifamily zoning districts or already had a district in place. Of these, 25 have applied for district compliance determinations from EOHLC, including 11 of the 12 rapid transit communities that had a deadline of December 31, 2023. These 35 communities have followed the guidelines and planned for the best locations for multifamily development, rallying community support to move forward and pass zoning ordinances. While receiving a compliance determination may take some time, the zoning is in place and active while the state’s review process occurs. New permitting could take place imminently in some of these new zoning districts. 3 of these municipalities — Lexington, Arlington, and Salem — have received either final or conditional determination of compliance with the law. The state has not rejected any compliance determination applications to date.

32 additional communities have submitted pre-adoption applications for EOHLC review. The state uses this pre-adoption review process to provide feedback on a proposed zoning district before a community takes the bylaw to a vote. These 32 communities have planned for districts they believe will achieve compliance and are looking for confirmation or feedback on necessary changes from the state before holding a vote and submitting a final compliance application.

Combined, this totals 67 communities that have been formally engaged with the state around specific district plans to reach compliance.

While that is already substantial progress, it does not fully capture the widespread ongoing planning efforts by many communities diligently working toward compliance deadlines. According to interagency technical assistance tracking, 162 communities (92 percent) have received technical assistance from the state or partners, such as MHP or their Regional Planning Agency. Planners and boards in these communities have been working proactively to find locations in their communities most suitable for multifamily housing within the guidelines and framework of the state compliance model. Many are already conducting or moving toward community engagement strategies to make sure residents and approval bodies understand and support the proposed changes. These efforts have been well-funded, and planners across the state have stepped up in amazing ways to figure out how to do this.

Non-compliance is being addressed. It can’t be a distraction.

Only two communities are currently out of compliance with the law: Milton and Holden. Despite good-faith efforts by planners and advocates in these communities to achieve compliance, the vocal obstinance emerging from a subset of community members and leaders has generated the appearance of controversy around a law that in many places has been far less controversial. It is not surprising the communities pushing back the hardest have a history of exclusionary housing behavior and an anemic track record of permitting multifamily housing. In contrast, those communities that have been working to unlock housing opportunities prior to the passage of 3A have also emerged as the ones most ready to comply. But we cannot continue to rely on proactive good actors to meet our regional housing needs. Changing this dynamic is certainly one of the aims of Section 3A.

The state should avoid capitulating to detractors by adjusting requirements. The guidelines were developed over an intensive period of research, discussion, and engagement with leaders and stakeholders to ensure there is sufficient flexibility to allow for context-sensitive decision-making without forfeiting impact. Key components of the guidelines emerged through this process, such as the consideration of affordability requirements and allowance for inclusion of Mixed-Use Development Districts. The fact that so many communities have already navigated the guidelines to plan for and approve zoning districts indicates the guidelines do not pose a hurdle too high to overcome.

While continued support to help Milton, Holden, and any other reluctant communities achieve compliance is paramount (MHP and other state, regional, and local partners will absolutely do our best to support these outcomes), the pro-housing community should be forward-looking. It was always a possibility that some communities may not comply with the law. The scope, scale, and enforcement of consequences for non-compliance will become clear over time, but we cannot continue to focus solely on this at the expense of forward momentum.

The bulk of our professional time would be better spent supporting and rewarding those communities that have pursued and achieved zoning that aligns with their community goals and our broader regional needs. Planners have created districts, stood in front of their communities to explain the changes, and in many cases adopted zoning aimed not only at ticking a compliance box but also at fulfilling longstanding community planning priorities. Those of us working in state government, advocacy, legislation, and other capacities who have a role to play in housing policy owe it to these communities to bring resources, strategies, and attention to bear on these new districts so that we are best positioned to support emerging housing opportunities.

The work is ahead of us, not behind us. Let’s invest in the success we are already seeing in communities that have adopted multifamily zoning pursuant to 3A. Communities that fight change may eventually be compelled to come along or else surrender the benefits that change can bring. But more importantly, communities that comply, and the people who live there now and in the future, will begin to see the benefits sooner if we all pivot towards investing in their efforts now.

Getting the most out of 3A districts requires effort and coordination.

Zoning sets the rules for how much housing is allowed and where it can go, but zoning doesn’t build housing or make great communities by itself. Moving forward means recognizing that zoning is a critical component of housing production, but it is merely one tool. The reality is that we must want to actually see change in these neighborhoods and we will have to put in the work to make the most of this new zoning. Think of zoning as a menu; there are plenty of delicious options to choose from, but until someone orders a menu item and the chef cooks it, nothing is actually produced.

Existing programs and funding decisions must be aligned with these important zoning changes. Funding for infrastructure, complete streets, and other great programs can be prioritized for communities that have met their 3A commitments. Executive orders, such as EO623 can more readily leverage public land for housing development. A statewide housing plan is in the works that will likely reflect the same housing, transportation, and climate imperatives that drove the MBTA Communities law. The newly formed state Commission to Unlock Housing Production will identify barriers to development and propose solutions to lower or eliminate those obstacles. Affordable housing subsidies can be targeted to promote and preserve economic and racial diversity within these changing neighborhoods. Legislation is an important part of the strategy, too, and the Affordable Homes Act has key measures including allowing accessory dwelling units (ADUs) by right statewide. Additional legislation targeting zoning may also be appropriate, especially since the MBTA Communities law does not include Boston, western Massachusetts, or significant parts of Central Massachusetts and the Cape and Islands.

Approved districts need to be analyzed for opportunities, which will vary by community.

Moving forward, each community will take a different path influenced by their zoning district decisions and unique local context. New zoning rules are being applied to existing neighborhoods with existing development patterns and differing levels of opportunity. An important next step is to uncover those opportunities and identify potential roadblocks, such as infrastructure needs, pedestrian and bike impediments, limited existing transit service, or insurmountable development costs. Spurring progress will require bringing attention and resources to complementary strategies to address these limitations.

Analysis of development potential, especially at a neighborhood scale, can be a complex endeavor. Luckily, the state has approved three districts so far, and the MHP Center for Housing Data team has taken an initial look at how the zoning in these districts relates to existing development patterns. This preliminary analysis is intended to provide a broadbrush sense of the potential development opportunities in these areas and should not be considered a definitive or thorough exploration of how much housing or new development these neighborhoods may see.

A brief explainer may be helpful in navigating this section of the brief. One important requirement of the law is that each community adopts a district that meets its required “unit capacity” minimum. This requirement has been a point of confusion for many, and given how technical and formulaic it is, it’s not difficult to imagine why. In the most basic terms, unit capacity measures the theoretical maximum number of residential units that could be produced on a given site (parcel) under the zoning, treating the site as undeveloped. This exercise is conducted for every parcel in a proposed district in an automated and consistent way by the Section 3A compliance model and these results are summed to measure the district relative to the total required unit capacity for the community. Below is a simple graphic explaining how to apply the unit capacity concept to a location that already has a building on it, in this case a duplex.

In the above example, while we use the unit capacity of four units to measure compliance, we know it does not reflect the net new housing units that the site can potentially accommodate based on the zoning rules. However, a simple subtraction of existing housing units from the estimated unit capacity provides us with an estimate of the net new housing potential on each site (the maximum possible housing units under zoning minus the number of housing units existing on the site). In the above example, the net new housing potential would be 2 (unit capacity of 4 minus existing units of 2 = 2).

To explore the utility of this net new housing potential metric, our team tested this method on the first three communities that have received final district compliance determinations from EOHLC: Arlington, Lexington, and Salem. We compared the parcel-level unit capacity calculations from these communities’ compliance applications to the parcel-level residential unit counts and standardized land use codes we’ve assembled for our density-explorer website, Residensity (check out the site; we have housing counts and residential density estimates for every square inch of the Commonwealth).

In the table below, we have summarized the net new housing potential within these districts by existing use. For example, on the table below, we’ve separately summed the net new housing potential for sites that are currently commercial, industrial, tax-exempt, mixed-use, vacant, or already residential.

The summary table indicates most of the parcels within these 3A districts are already developed to some extent as only a small share is currently vacant land. In Arlington, over 85 percent of the net new unit capacity is on parcels already developed with residential uses. In contrast, Lexington and Salem have about half of their potential new units on commercial parcels. The different composition reflects communities’ varying approaches and priorities in designing their districts and will have implications for how neighborhoods may change over time and how quickly. More detailed analysis will need to determine each community’s and district’s blend of development, redevelopment, and infill strategies for housing production.

However, even this initial analysis indicates that Arlington would greatly benefit from strategies and support for densification of existing housing sites while Lexington and Salem might benefit from strategies aimed at commercial conversions, including mixed use development or demolition and remediation of obsolete commercial properties.

Overall, the net new housing potential numbers presented in the table are promising, with ample additional capacity across all three communities. While much attention has been paid to the “unit capacity” metrics used to determine legal compliance, these numbers are a better measure moving forward of how zoning translates to development potential. However, it is critical to view these numbers with an understanding that development and redevelopment do not happen overnight. Salem is a great example as to how the city was able to comply with Section 3A using an existing zoning district, meaning these zoning rules have already been in place for some time. While some development has taken place in this district since its adoption, the above table shows that there is still additional capacity to leverage for multifamily housing, and finding and deploying the right resources and strategies will be critical to fulfilling this full potential for production.

This capacity may not be easy or quick to leverage, however, and may never come to fruition, making it difficult to interpret or estimate exact impacts. While metrics are important and necessary for determining compliance with a zoning law, they can also lead to misunderstanding and confusion if not properly contextualized. Therefore, further analysis and quantification of new housing development opportunities will go a long way toward demystifying the nebulous impacts of zoning, and this exciting research work is underway by multiple teams across the state. New tools and insights will emerge from this work, and these products will be instrumental in guiding effort and resources to the right places.

The success of the MBTA Communities Law will come from coordinated community development that improves our quality of life and regional accessibility.

While some coverage of 3A has made the point that the potential impact has been overstated because it is only about zoning, that framing, while correct in many ways, fails to recognize several important points.

First, zoning may be just a change to the rules, but it is also a key that unlocks the door for other strategies. We already have so many tools to explore and take advantage of the potential more permissive zoning brings. With a streamlined permitting process and the knowledge that a community has intentionally planned for multifamily housing, our existing planning, development, and financing mechanisms can be brought to bear. So, while zoning has long been the tool that was missing from our toolbox in many locations, we already have many of the other tools we need to build once that door is finally unlocked (e.g., housing subsidies, streetscape improvements for pedestrians/cyclists/micromobility, infrastructure funding, energy efficiency strategies, etc.). So much of the multifamily housing development in Massachusetts has been approved through lengthy and onerous special permitting processes. With a widespread regional increase in low-threshold by-right permitting, there are prospects for increasing the reach and efficacy of these existing tools.

Second, Section 3A implementation has already begun recalibrating how we approach issues of housing and zoning at the state, regional, and local level. This piece presented a case for increased coordination of resources across state agencies and a concerted effort to deploy resources to take advantage of emerging opportunities in 3A districts. Furthermore, the coalitions, relationships, and financial support mechanisms that have already been created during the zoning implementation process will serve the community development needs that lie ahead. We have not seen this level of state leadership, resource deployment, and coordination around housing policies in quite a long time. This outcome, while perhaps not an explicit goal of Section 3A, is a development that gives the Commonwealth a better chance of capitalizing on new zoning opportunities.

Third, it is tempting to look at Section 3A as an endpoint. For many years housing advocates have pushed for zoning reform like this, and the passage of the law and subsequent district adoptions feel like tremendous progress already. That is not, and never was, the end goal, and a “wait and see” approach for newly adopted zoning districts will never get us the denser, vibrant, mobility-rich communities we need in Massachusetts to meet our housing, transportation, climate, and socioeconomic goals. We must step into our sense of agency in the coming years and put in the hard work of neighborhood development within these targeted districts. That will take time and resources, but the investments will be worth it. Zoning is not the end goal, but a steppingstone toward a more functional region with neighborhoods and housing opportunities that increase the quality of life for all residents.

For additional information about this brief or upcoming topics, contact Tom Hopper or Ellen Marya.

For more information contact MHP Communication Manager Lisa Braxton, (857) 301-1526.