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MBTA Communities Upzoning Guidelines, Explained (Plus Some Discussion and Commentary)

By Luc Schuster and Anne Calef

January 23, 2022

MAY 3, 2023 UPDATE: This article reviewed the MBTA Community Guidelines as of January, 2022. These guidelines have since been revised, and are now available at "Multi-Family Zoning Requirement for MBTA Communities." The following report is now out of date, and we encourage readers to use the revised guidelines available at the link. 

As our regional economy grows, we need more housing at a wider range of price points. But the state has left most housing policy decisions up to local governments that are not elected to meet our state or region’s shared needs. This mismatch of interests has led many communities with valuable transit access to adopt single-family-exclusive zoning rules that ban the construction of modest, diverse housing options like townhomes, duplexes and triple-deckers. In addition to rising housing costs, this has contributed to persistent residential segregation by race and income and higher CO2 emissions from car-centric development patterns. We have an intensifying housing shortage with costs rising as a result.

To work on these challenges, the state legislature passed a law in January of 2021 requiring that all “MBTA communities” develop at least one zoning district within a ½ mile of transit that legalizes multi-family housing construction. While it leaves significant latitude to individual city and town governments, this law represents an important shift, with the state taking action to ensure that most eastern Massachusetts cities and town contribute to addressing our regional housing shortage.

This brief is organized into two parts, which you can explore by scrolling down or clicking on the buttons below.

The Basics

An explanation of new draft guidelines from the Department of Housing and Community Development (DHCD) for implementing this law, designed for people without a planning background.

Discussion and Commentary

An exploration of the potential benefits, issues, and challenges that are created by the draft guidelines.


Key provisions of the original Section 3A law that passed in January of 2021

January 2021 economic development bill added a new Section 3A to the state’s zoning laws requiring that all “MBTA communities” adopt a zoning district with these features:

  • The district must be of “reasonable size.”
  • Multi-family housing must be allowed at a minimum gross density of 15 units per acre.
  • This multi-family housing must be allowed “as-of-right.”
  • The zone must be no more than ½ mile from a commuter rail station, subway station, ferry terminal or bus station.
  • Allowable housing must be suitable for families with children and have no age restrictions.

This economic development bill included other provisions to help facilitate home building in Massachusetts, including the elimination of the 2/3 majority requirement for passing certain local zoning changes related to housing production (often referred to as “housing choice” legislation) and the creation of procedures to discourage meritless legal challenges to proposed housing construction. This explainer focuses on the MBTA zoning requirement, although these reforms are all part of a combined effort by the legislature and the Baker Administration to facilitate more multi-family housing production regionwide.

As with many laws, the specific language that passed provided a broad framework, but did not on its own have sufficient detail to direct on-the-ground implementation. Therefore, DHCD was tasked with writing such guidelines. The agency spent roughly the past year drafting them and released detailed draft guidelines on December 15, 2021. DHCD is soliciting feedback on the draft through March 31, 2022 and will then finalize the guidelines in the summer of 2022.

Definition of “MBTA Community”

MBTA community” sounds like a label that only applies to municipalities with MBTA transit stops, but the state’s definition is much broader. Municipalities count either if they themselves have transit stops OR if they are located adjacent to a community with one of these stops. 

In fact, 175 cities/towns count as “MBTA communities.” That’s the vast majority of eastern Massachusetts and half of the entire state. The map shows all 175 of these communities by specific type, which affects each community’s capacity calculation, described below.

Boston is exempt from the law.

Map of 175 MBTA communities in upcoming
The 175 "MBTA Communities" 

The Core of DHCD’s Draft Guidelines: The Two-Part Test for Determining “Reasonable Size”

A primary question heading into the guidelines-drafting process was: How would DHCD define “reasonable size,” given the vague language from the original law? Planners often use a ½ mile radius for defining a reasonable walk zone around transit. Would DHCD use this full walk zone definition, or would it allow multi-family districts to be smaller than the full ½ mile radius?

Ultimately, DHCD is proposing two-part test for determining “reasonable size,” and the final determination varies by community. Multi-family zones must meet both of the following requirements:

  1. Be at least 50-acres large, with a minimum gross density of 15 units per acre. This is far less than the full ½ mile radius. For comparison, a ½ mile radius walk zone is about 500 acres, or ten times as large as this 50-acre requirement. As described below, some zones will likely be significantly larger than 50 acres, but few, if any, would have to develop zones that occupy a full ½ mile radius.
  2. Accommodate a minimum number of multi-family units (the “capacity” requirement), which varies for each community based on the calculation described below.

For “capacity,” DHCD is advancing the idea that the higher a community’s transit service level, the higher its expectation should be for producing housing; it makes sense to build more dense multi-family housing around, say, an Orange Line station in Malden than around a Commuter Rail station in Ashland. The state runs this transit network to serve the needs of the full region, and so this variable capacity expectation is a step toward requiring housing contributions that roughly match the level of transit service provided by the state.

DHCD’s approach to calculating capacity is somewhat crude, multiplying a municipality’s total number of existing housing units by a percentage that varies across four different transit service types: Subway or Light Rail (25%); Bus (20%); Commuter Rail (15%); or MBTA-Adjacent (10%), for communities that don’t have transit access themselves but that border a municipality that does. It is unclear how DHCD selected each of these percentages, but they likely reflect rough judgment calls that use round numbers.

Below are a few examples of these proposed capacity calculations. Click here for a full spreadsheet with designations and capacity calculations for all 175 MBTA communities.

capacity table examples
*See 750-unit minimum capacity discussion below for an explanation of why this percentage isn’t 10%, like it is for Chelmsford.

Community types are designated based on the highest (or most frequent) level of transit service a community receives, and since “service” is defined using a ½ mile radius as the crow flies, some communities receive a higher designation due to proximity to a higher-service transit stop in a neighboring town. Arlington, for instance, is designated “Subway or Light Rail” rather than “Bus” because the Alewife subway station in North Cambridge is within a ½ mile walk of East Arlington.

Required Zone Sizes, Allowable Zone Locations, and the Relationship to “Capacity” Calculations

As noted above, all zones must be at least 50 acres in size. Beyond this, communities have a good deal of flexibility. A few examples of this flexibility include:

  • Parts of the multi-family zone can extend away from a local transit stop, so long as at least half of it is within a ½ mile radius of that stop. For areas with insufficient developable land near a transit stop—due to things like existing wetlands and public parks—DHCD is willing to consider requests to locate the multi-family zone further away.
  • If zones maintain a minimum of gross 15 units per acre, they can be larger. This means that communities can meet their requirements by legalizing sufficient density within a 50-acre zone or they can push for more moderate density across a larger zone.  Take a community like Belmont, for instance. Belmont’s new zone must allow for at least 2,176 multi-family units. To meet that requirement, they could create a 50-acre zone around, say, Belmont Center (which has bus service) that allows for 44 units per acre, they could create a 145-acre zone that allows for 15 units per acre, or they could do something in between.
  • The entire zone need not be set at a uniform density level, so long as the district overall allows for 15 units per acre. For example, a town could zone for high density along a main street through a mixed-use sub-district and then have another sub-district on side streets that allows for lower density. This ability to use sub-districts adds gives communities flexibility to create districts that make sense relative to their existing planning initiatives and neighborhood context.
  • Communities can even comply by creating a non-contiguous overlay district, as long as at least one section is at least 25 contiguous acres and all other parts are at least 5 acres large.

Sanctions for Communities That Do Not Comply

This law is a legal requirement of all MBTA communities, meaning that they are expected to comply on their own. For those that do not comply, the state will withhold state grant money from three programs, the Housing Choice Initiative, the Local Capital Projects Fund, and the MassWorks infrastructure program. 

The three programs vary in size, but MassWorks is by far the largest, awarding $66.5 million in grants in FY 2021 to 50 communities for projects ranging from street redesign in Acton to sewer upgrades in Dartmouth. The Housing Choice Initiative (HCI) gives communities that meet state housing production and planning expectations exclusive access to the HCI grant program—much smaller, at $5 million FY 2021—as well as “bonus points” when applying to many other state grant programs. Finally, the Local Capital Projects Fund receives revenue from the casino tax and gaming license fees and has historically been used to support subsidies for public housing authorities ($8 million in FY 2021).

Click here to download a spreadsheet with MassWorks and Housing Choice grant funding by community over the last seven years.

This analysis shows that since 2011, 37 percent of MBTA communities (64 out of the 175) have not received any funds from the Housing Choice Initiative or MassWorks. So, it does seem possible that some communities could violate this state requirement and forgo these sources of state grant funding. Beyond withholding state funds, there could be legal avenues for addressing communities that do not comply. Perhaps, for instance, home builders looking to build multi-family housing near transit in a non-compliant community could sue and request a judge to demand that their permit be approved.

The 750-Unit Capacity Minimum for Smaller Towns

By requiring all districts to be at least 50 acres large at 15 units per acre, DHCD has effectively created a capacity floor of 750 units (50 multiplied by 15), even if this exceeds the percentage-based unit capacity requirement. That’s why in the table above, Ashby has an effective capacity assumption of 60 percent, even though the official capacity requirement for MBTA Adjacent communities is only 10 percent of existing housing. Just over half of all communities (79) are at this 750-unit capacity floor.

What 15 Units Per Acre Looks Like in Practice

All different sorts of housing could meet the gross 15 units per acre minimum, but in broad strokes this approach requires modest density in the range of duplexes, townhomes, carriage houses or very small apartment buildings. Fifteen units per acre is a density level far short of requiring larger apartment buildings. Even classic triple deckers with small yards are often at a density of more than 15 units per acre, since many classic Greater Boston triple deckers were built on relatively small plots of land before minimum lot size requirements were written into local zoning codes.

Maxwell's Green Townhomes
Maxwell's Green, Somerville

For one visual, see the picture (right) of townhomes at Maxwell’s Green in Somerville. There are 15 side-by-side townhomes in this development (not all shown) each with small yards and a shared green space. Together they sit on roughly one full acre. These townhouses are directly next to the forthcoming Magoun Square Green Line stop and could be used as a location for Somerville’s required multi-family zone.

The law also uses “gross density” rather than “net density,” meaning that land occupied by public rights-of-way, parks and other nonresidential uses count towards the total land included in the state’s calculations. So, if a multifamily zone has more of these other current land uses, they’ll need to allow for more housing production to meet the gross 15 unit per acre expectation.

By contrast to the townhomes above, many communities currently have zoning rules that only allow for single-family homes, even directly next to valuable transit stops. Below, for instance, are a couple of examples of single-family homes each within three blocks of the Wellesley Hills commuter rail station. We show these not to point fingers at individual homeowners—anyone living here now is living in the only type of housing currently allowed by law—but to help people who may not be familiar with these higher-income suburban areas better visualize the lack of housing density that’s currently in many of these transit-rich areas.

Single family home 1
Single family home 2

What 50 Acres Looks Like in Practice

Below are two examples of what 50-acres looks like in practice, one for Somerville and one for Winchester. Somerville is composed of 2,511 acres of developable land (according to preliminary analysis from MHP's Center for Housing Data), so a 50-acre zone represents 2.0 percent of this land area. Winchester has roughly 3,084 acres of developable land, so 50 acres make up 1.6 percent of its land.

The hypothetical 50-acre zone on the left is drawn to the north of the Davis Square Red Line station in Somerville. The dotted circle shows a ½ mile walk zone around the station (again, a full ½ mile walk zone is roughly 500 acres large).

All housing in the full ½ mile radius around the Davis station is currently very close to 15 units per acre (14.5 units per acre, according to MHP’s TODEX estimates), so much of this existing housing development could be used to satisfy Somerville’s capacity requirement, assuming it adopts multi-family zoning that meets the new guidelines.

On the right is another example of a hypothetical 50-acre zone, this time near the Wedgemere Commuter Rail Station in Winchester. This is a station area where the residential development that does exist is almost exclusively single-family, even though from here the train takes only 16 minutes to get to North Station in Boston. 

Davis Sq., Somerville

Davis Sq upzoning map

Wedgemere, Winchester

Wedgemere upzoning map

It’s worth noting that less than a mile north of the Wedgemere stop is the Winchester Center stop. Winchester could satisfy the 50-acre requirement in a portion of the land area around the Wedgmere station, leave most of the land area around that stop unchanged, and would still not even touch any of the land around the Winchester Center stop.

Unlike Davis Square where most of the area in a half-mile radius of the station is already zoned for multi-family housing, the area around Wedgemere is currently zoned for single-family homes only and is at a current density level of 2.9 units per acre, according to MHP’s TODEX estimates.

While Somerville will need to zone more than 50 acres if it zones at only 15 units per acre (to meet its 9,067-unit capacity), Winchester needs significantly less area and/or density because its capacity is just 1,627.

Some communities will be able to comply by rezoning around existing housing that’s already at 15+ gross units per acre, meaning no net new housing would result.

The law effectively sets an expectation that all MBTA communities zone for a minimum amount of multi-family housing to contribute toward meeting our region’s shared needs. Communities that have already provided some, or all, of their capacity requirement can comply without allowing for net new housing to be built. The guidelines call for districts that are largely contiguous, however, so communities cannot assemble a piecemeal collection of smaller zones around existing multi-family clusters to meet this requirement.

In a few instances, communities may have already adopted the necessary as-of-right zoning that meets their capacity requirement. It’s likely that in most others, new zoning will have to be drawn around existing housing, but in these cases, it’ll be a smaller administrative task to comply.

The Meaning of “As-of-Right”

Oftentimes what zoning rules seem to allow on paper can still in practice be very hard to build. This is because local communities can erect procedural requirements to slow or even stop projects that should meet the spirit of the zoning code.

“As-of-right” zoning is one attempt to ensure that zoning rules are implemented more fairly and efficiently, requiring that the building permit process is not more cumbersome than absolutely necessary. Specifically, these draft guidelines state that new home construction should happen without needing a special permit or variance, which can often slow the process considerably and ultimately push up housing costs. Communities may require a basic site plan review to confirm that a plan complies with the zoning ordinance, but an otherwise eligible project should go through without lengthy delays and legal costs.

How This New Requirement Is Different From 40B

The multi-family upzoning requirement is a new law that will function separately from the longstanding 40B law. Chapter 40B has been known as the state’s affordable housing law, designed to ensure that at least 10 percent of all housing units in each community are “affordable.” In some ways, these state housing laws could be thought of as complementary; 40B focuses on generating income-restricted housing for lower-income families, while the multi-family upzoning law focuses on generating new market-rate housing. These new zones could, however, still encourage more income-restricted housing through less direct mechanisms like:

  • Affordable housing developers becoming more competitive with market rate developers, as multi-family housing is legalized in many more parts of the region.
  • Families with rental vouchers gaining access to communities that don’t currently have much moderately-priced rental housing.
  • Communities choosing to add inclusionary zoning requirements to their new zones (see Discussion and Commentary section of this brief for more detail on this option).

Another key difference is that 40B functions in a one-off manner with developers appealing to build specific projects in communities currently below the 10 percent affordability requirement. Relatedly, many 40B projects are proposed in remote locations far from transit or downtowns because the sites area cheaper and have fewer abutters to potentially resist the project. The new multi-family upzoning guidelines, by contrast, expect neighborhood-level planning from each municipality, aiming to encourage more complete plans for potential new housing near transit.

The Difference Between Changing Zoning and Requiring New Housing Production

Hearing talk of zoning for multi-family housing can lead to a confusing sense that homes in existing single-family-exclusive zones would somehow have to be redeveloped into multi-family developments. That’s not the case. Zoning sets the rules for what’s allowed to be built, but it is not a requirement to build anything new on a given plot of land. Property owners in new multi-family zones could absolutely keep their single-family homes as-is. It would just give them the option of redeveloping land so that more families could live near transit, if they chose to do so.

Areas that currently have single-family-exclusive zoning on the books, by contrast, actually have eliminated all other housing options like townhomes, duplexes and modest apartment buildings. Undoing single-family-exclusive zoning would just make these sorts of homes an option in places where there’s market demand for it.

Next Steps in the Process

The Baker Administration is seeking comment on the draft guidelines until March 31, 2022, and then will issue final guidelines in the summer of 2022.

Additionally, cities and towns are already starting to think about the coming work of developing these multi-family zones. So, while this is an important window of opportunity to shape housing policy at a state level, the coming months will also be an important time for local action to start developing well-designed new zones given their local context.

Subway or Light Rail and Bus communities need plans in place by 2023. Commuter Rail and MBTA Adjacent communities need zones in place by 2024. 


Local planners, researchers and advocates have been working hard to understand the likely impacts of these draft guidelines. Implementation is tough to predict because final housing production will depend on decisions of 175 different cities and towns and of private landowners and homebuilders. And, again, all of this deals only with what’s allowable by law, rather than being a requirement to build anything on a given plot of land. At the end of the day, though, these draft guidelines do appear to represent a significant shift toward a more collective approach to housing production, with the state now expecting most communities in eastern Massachusetts to allow at least some modest multi-family housing as-of-right on a small portion of their land. This has not been the case to date, with the state’s 40B law being the only provision stopping municipalities from adopting single-family-exclusive zoning across most of their developable land.

What follows is some discussion of issues that have arisen over the course of our research. It is far from exhaustive, and we’d welcome feedback and further thoughts. This is an important opportunity to maximize the potential of these guidelines. 

The original law—and DHCD’s guidelines—include no expectation that communities provide any “affordable” units for lower-income families.

Taking a market rate housing production approach, this law is focused on improving affordability for people renting or buying homes on the open market. But we know that those who are struggling most in our region will not be able to afford most market rate housing, even if we are able to halt the cost increases we’ve seen in recent years. Therefore, there’s no question that the legislature should do more to ensure that lower-income families can afford safe, stable housing in every community in Greater Boston—through mechanisms like increased funding for rental vouchers and nonprofit affordable housing developers. The framework of the original law likely does not allow for DHCD to add a low-income affordability requirement through the guidelines-writing process, but the DHCD has made clear that communities can add affordability requirements to their new zones, as long as they are “financially feasible and do not unduly impede the construction of new multi-family housing in the district.” Communities could also create these districts through the 40R process, which includes financial incentives for including affordable units. 

It’s worth emphasizing that there’s a synergy between efforts focused on housing production and those focused on providing income-restricted housing for lower-income families. Anything we do to reduce market rate housing costs ensures that a given amount of money used to help subsidize the cost of housing for lower-income families can ultimately support a greater number of them. And even just building more high-end rental housing reduces competition for existing rental housing.

Relatedly, anything that allows for more multi-family housing construction as-of-right will help make affordable housing developers more competitive in these new zones. Along with the housing choice voting change, the conditions would likely be more favorable for affordable housing production in many suburban municipalities.

DHCD calculates “capacity” based on past housing production, rather than a forward-looking estimate of a community’s real multi-family housing potential.

While there’s likely a rough connection between current housing levels and the places where it makes most sense to concentrate further multi-family housing construction, we know that there are many transit-rich communities relatively close to the urban core that have allowed for very little multi-family housing construction to date. These places have high potential for new housing construction but low levels of current housing. Basing capacity calculations on current housing levels for communities like these serves to lock in a lower capacity expectation than might otherwise be the case.

Allowing communities to comply by rezoning around existing housing that’s already at 15+ units per acre means that this law will have less impact in our region’s most transit-rich areas.

On the one hand, this can seem like a real downside, since some of the most transit-rich areas of our region (like Malden, Cambridge and Somerville) could still accommodate significant new housing. It’s in these places that we’re likely to have the greatest climate mitigation effects since existing mixed-use neighborhoods are the easiest places to live, work and play in without depending on a car. On the other hand, perhaps this is a reasonable equalizing approach where communities that have already contributed meaningful numbers of multi-family units are expected to contribute less toward this new requirement, and communities that to date have not contributed their fair share will finally be expected to do more.

Since DHCD is adopting a variable approach to “reasonable size”—by calculating different capacity minimums for each community—it may have flexibility to shift instead to a calculation that uses “net new capacity” as the requirement, rather than the current guidelines that would allow newly drawn zones to generate little net new zoning capacity. Adjusting to a “net new capacity” would shift the approach from being an equalizing strategy to one that expects all communities to increase their effective zoning capacity, even if they’ve contributed a lot of multi-family housing to date.

The three state grant programs being used as an enforcement mechanism may not be large enough to ensure broad compliance.

As noted above, 37 percent of MBTA Communities (64 out of 175) have not received any funds from the Housing Choice Initiative or MassWorks since 2011. These programs largely fund capital projects that are one-time in nature, so although it’s possible that this sanction could compel compliance—even for communities that haven’t received funding in the last seven years—it does suggest that these specific programs are not absolutely essential for the regular functioning of many municipal governments.

Unfortunately, some of the Commonwealth’s wealthiest communities—those most able to pay for their own infrastructure needs—have also been most exclusionary and resistant to multi-family housing construction. It may be hard in some of these places to achieve an affirmative vote of the city council or town meeting to adopt a new zone that’s in compliance with the law. Compliance with the law will require that affirmative vote of the city council or town meeting, and places with open town meetings, rather than representative ones, may be especially susceptible to hyperlocal concerns about neighborhood change and less sensitive to the stick of receiving state grant funding for other programs.

This enforcement mechanism was spelled specifically in the original law, so DHCD likely has little leeway to shift it during the guidance-writing process. But state leaders can make clear to municipalities that the new law is a requirement nonetheless, meaning that they are expected to adopt zones that comply. Ultimately, if many communities do refuse to comply, there may be some legal challenges that aim to force compliance, and, ultimately, this could be an area for further legislative action to strengthen the compliance mechanism.

The 344,000-unit capacity total from these guidelines is ultimately far higher than any reasonable estimate of net new housing construction that might result.

Some discussion of the draft guidelines has focused on the potential increase in regionwide zoning capacity of 344,000 units (the total of all 175 communities’ minimum capacity requirements), generating a sense that these are very high numbers. While on the one hand, increasing the zoning capacity of our region by this much really does represent a meaningful change, it’s important to be clear that this zoned capacity only refers to what is allowable by law, rather than serving as a production mandate. As noted earlier, tens of thousands of existing units will make it easier for communities to comply with the law.

On top of that, even net new zoned capacity is far from actual new housing construction because many existing property owners will choose to keep their properties as-is or to redevelop their property to a lower level than what is allowed. In our recent Zoned Out report, Boston Indicators and the Brookings Institution modeled a similar TOD upzoning proposal for Massachusetts and we used two different scenarios for projecting likely redevelopment in suburban Commuter Rail station areas, estimating that between 5 and 10 percent of residential parcels would be redeveloped within 10 years.  

Now, to be clear, adding “just” tens of thousands of new housing units would be an important step in addressing our regional housing shortage. But nothing close to 344,000 net new housing units would likely get constructed under DHCD’s proposed approach.

Some of these new zones may end up being transit-adjacent, rather than truly transit-oriented, walkable 15-minute neighborhoods.

Developing areas that are truly transit-oriented requires more than simply producing more housing. They need good streetscape design to encourage walkability. They need a mix of uses so that people can live, work and play all within relatively close proximity. Since it’s focused only on multi-family construction, this law on its own falls far short of guaranteeing this sort of full transit-oriented vision. And given its specific design, communities do have significant leeway to locate their zones in areas that wouldn’t in practice feel very connected to the nearby transit node.

Boston Indicators and the Massachusetts Housing Partnership described a vision for more vibrant multi-modal neighborhoods in our recent paper 15-Minute Neighborhoods: Repairing Regional Harms and Building Vibrant Neighborhoods For All. Legalizing multi-family housing is a necessary precondition for developing 15-minute neighborhoods, but it isn’t sufficient on its own. Please see the policy section of that paper for discussion of many other complementary policies that are worth our consideration as a complement to this new law.

While the 750-unit capacity floor for smaller communities may seem like a lot, it applies only in communities with very little housing to begin with.

Discussing the 750-unit capacity minimum for smaller communities like Ashby as a 60 percent capacity expectation is accurate, but this framing can make the guidelines sound more ambitious than they really are. Compare this, for instance, to states like California and Oregon that in recent years have eliminated single-family-exclusive zoning by allowing duplexes as-of-right. For places that go from single-family zoning to two-family zoning (or even single-family to accessory dwelling units as-of-right), that’s comparable to a 100 percent “capacity” expectation using the DHCD framework. That framing makes it sound like a huge jump. But most planners have talked about legalizing duplexes as a bare minimum reform that legalizes missing middle housing, rather than an extreme upzoning approach.

While some of these communities feel far away from the urban core, they all do, for the most part, have some transit access in at least a portion of their town. These guidelines expect them to allow some cluster of townhome-style development relatively close to those station areas. Now, to be clear, some new housing built in this MBTA upzoning context would not meet the spirit of what most planners mean by walkable and transit-oriented. In fact, if done in places near low-ridership commuter rail stations with little other walkability, some of the development that results in these areas could actually increase vehicle miles traveled. But if this law gets some legalization of townhomes (which can hit 15 units per acre) in less transit-rich areas of the region, in addition to all the other more truly TOD upzoning, this may be an imperfect form of multi-family upzoning that’s still better than the status quo.

Requiring a 50-acre multi-family zone in 175 communities is a meaningful new requirement from the state, but it is still far short of requiring multi-family legalization municipality wide.

To many smaller communities, this new requirement will no doubt feel like an unprecedented new mandate from the state. But it’s worth keeping in mind that even for smaller geographies, 50 acres represents a small fraction of the overall municipality. As noted above, 50 acres make up roughly 2 percent of communities like Winchester and Somerville. For a larger municipality like Leominster, 50 acres constitutes just 0.4 percent of developable land.

This law focuses on encouraging multi-family housing near transit, but that’s not the only place where we need more housing.

Building more dense, walkable housing near transit makes good planning and environmental sense, and that’s the focus of this law. But it also makes sense to encourage more housing construction in communities with strong schools, so that we maximize the number of kids with access to our region’s best schools, or along existing Main Streets, to boost local economic development. The proposed guidelines allow for some flexibility of location within municipalities but is mostly silent on these other important factors in directing where housing production might be of most social benefit.

Expecting greater zoning capacity from communities with higher transit service makes sense, but placing 175 different communities into one of only four community types leads to some horizontal equity concerns.

Recent research from the Metropolitan Area Planning Council helpfully demonstrates how crude service type designations are a weak predictor of actual transit quality, as measured by access to jobs within a 45-minute commute. There is a correlation, but it’s relatively weak. Relatedly, there’s an especially wide range in service quality for communities with bus service. High-frequency bus stations could arguably be treated more like light rail, whereas commuter rail stations could arguably have higher requirements than low-frequency bus stations.

DHCD’s service type approach also generates some odd categorizations for some communities that neighbor higher-service communities. For instance, it treats Wellesley and Weston the same as Cambridge and Somerville—all are designated “Subway or Light Rail,” and are therefore expected to zone for 25 percent of their existing housing stock. Wellesley and Weston have Commuter Rail stops within their town boundaries but are treated as “Subway or Light Rail” because they’re both within ½ mile of Green Line stops in neighboring Newton, even though those stops are only marginally walkable from certain edges of town.

The fact that this law issues zoning expectations, however, and not actual production mandates, should help somewhat with these horizontal equity concerns. Our region has struggled for years with growing housing shortages caused in large part by the local adoption of single-family-exclusive zoning. As long as the law is relatively ambitious in requiring some multi-family zones in all MBTA communities, and if the capacity imbalance errs on the side of requiring more from some places like Wellsley and Weston than might have been expected, that may be for the better (assuming they ultimately comply with the law). 

Developing, and adopting, well-designed multi-family zones takes time and thoughtful community engagement, and DHCD’s timeline could be tough for some smaller communities.

Communities will have to start developing these new zones immediately this spring. Developing thoughtful zones that comply with the guidelines, generate community input and buy-in, and secure an affirmative vote of a city council or town meeting, is a big lift, even in the best-staffed municipalities. Some smaller municipalities have very lean planning teams, so these steps will be even tougher in these contexts. Commuter Rail and MBTA Adjacent communities do not need zones in place until 2024, so that does give them some more time. Subway or Light Rail and Bus communities, however, need plans in place by 2023.

DHCD says they recognize this and has offered technical assistance to all communities and is offering a range of planning grants. Additionally, planners and researchers at the Massachusetts Housing Partnership, a quasi-public agency working closely with DHCD, will be available to help all year. 

Nonetheless, this all may prove to be difficult to achieve on the current timeline proposed by DHCD. And while modest in many ways, these new expectations may feel to many communities like a significant new expectation that could take a while to get comfortable with. Therefore, one alternative to requiring full, adopted plans within a year or two could be adopting a slower phased approach where, say, communities need to pass plans that legalize 10 units by right within three years and then the full 15 units by right within five years. These new zones will hopefully shape development for decades to come, and so trading some urgency for increasing the likelihood of higher municipal buy-in could be worth considering.

This guidance process will allow for more flexibility than a regulations process would have.

The original law directed DHCD to develop guidelines, not regulations. There are several legal distinctions between these two processes, but the upshot is that guidelines are easier to change and modify over time. This gives DHCD, and outside advocates, more opportunity to shift implementation of this law over time as we learn more about its on-the-ground effects. This approach can help us all treat this law as a statement of new priorities and shared goals—that all MBTA communities should be contributing multi-family housing to help meet our shared housing needs—and encourage improvements over time to help ensure we meet these goals in practice. In fact, DHCD would be wise to communicate publicly the likely need for some tweaking and fine-tuning over the next few years as implementation is rolled out.

The original law—and therefore DHCD’s proposed guidelines—requires one transit-oriented district for all MBTA communities, even though many MBTA communities have more than one transit stop.

There is not a strong policy rationale to expect multi-family zoning near only one transit stop in a community that has, say, two commuter rail stations. Unfortunately, the original law only requires “at least 1 district,” so developing an expectation that multi-family housing be near all transit stops in our region would likely require follow-on legislation and is not something DHCD has the power to add through this guidelines process.

State zoning reform is a complex undertaking, so we should view this as a work in progress that will require regular tweaks and, likely, follow-on legislation.

Regardless of the initial guideline quality, no doubt many challenges will emerge as we work through implementation. Much will hinge on DHCD’s ability to assess the level of good-faith attempts being made by municipalities to comply. And the legislature may need pass follow-on, rather than viewing this as a one-off action. In fact, there are already efforts to expand a version of this model to some other non-MBTA communities. Companion bills H1448 and S871, for instance, would apply the law to communities with Regional Transit Authority bus service and they both include a minimum 10 percent affordability requirement. 

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