Brookline Trails Boston-Area Peers on Housing Target
How much housing is Brookline permitting compared to its metro-Boston peers? A recent Boston Globe article prompted me to dig into this question. The article describes an initiative undertaken by the Metro Mayors Coalition (MMC) - a consortium of 17 Boston-area municipalities, including Brookline - to produce 185,000 new housing units between 2015 and 2030; this target was based off of economic and demographic analyses.
The MMC’s initiative provides a rare opportunity to step back from the rhetoric on housing policy and look at results in Brookline and among its regional peers. Through the first ten years (2015-2024), the MMC municipalities permitted 76,628 units, which puts them on track to produce only 62% of their goal, or 114,000 homes, by 2030.
How many housing units did each of the MMC communities permit between 2015-2024?
The MMC’s data shows that Brookline permitted 1,052 housing units during this ten-year period, ranking 13th out of the 17 communities. Perhaps unsurprisingly, Boston permitted the most housing - over 36,000 units - which was about 34 times more than Brookline.
But Boston is much larger than Brookline - we wouldn’t expect smaller municipalities to permit housing at the same scale as a major city. And while the Globe article provided additional context, it ultimately didn’t get at the question I want to answer: which municipalities are permitting more housing relative to their size.
What was Brookline’s permitting target?
The MMC housing target is a collective goal and municipalities did not publish individual targets for themselves. Brookline, despite having several planning documents related to housing development, also does not appear to have its own overall permitting target for housing that feeds into the MMC’s collective goal.
The town’s Housing Production Plan (HPP), last approved in 2024, specifically concentrates on developing affordable housing units to ensure Brookline is in compliance with the Commonwealth’s affordable housing law (Chapter 40B). This law requires municipalities to maintain a subsidized housing inventory of at least 10% of its total housing supply. The HPP set a goal of creating 139 subsidized housing units per year for as long as the town remained under the 10% benchmark. However, this plan does not present an overall permitting target and it was authorized at the end of the period we are looking at for this analysis, so it’s not particularly helpful in understanding how many housing units Brookline anticipated permitting for this MMC initiative.
Another potential source for a housing target is Brookline’s Comprehensive Plan, which is currently being updated and will touch on housing and land use priorities, among other topics. The town’s last comprehensive plan was published in 2005 and did not include housing development targets, though one of the inputs for its population growth forecast for the town was an increase of 107 new housing units per year, which was the 30-year average annual growth trend between 1970 and 2000. But yet again, this plan did not cover the period we’re looking at and it didn’t set overall housing goals.
In the absence of specific targets from Brookline and the other communities, we’re left to derive our own. For this analysis, I created equitable targets for each community by weighting the total annual target of 12,333 units by each municipality’s proportion of the region’s population. Another alternative would be to use each municipality’s proportion of the region’s total land area, but I feel the former is more representative of each community’s relative size.
Of the 1.6 million residents in the MMC region, Brookline’s population accounts for approximately 3.7% (and for those wondering, its 6.8 square miles is 4.1% of the region’s land area). That translates to a target of 458 units each year, 4,580 units through the first 10 years of the initiative, and 6,870 units by 2030.
For context, during a period of growth in the 1960s, Brookline added an average of 358 housing units per year. Is 458 units per year a reasonable contribution target for this regional initiative, and did communities expect to share the housing goal proportionately? I’m not sure, but weighting the overall target normalizes each municipality’s permitting performance and allows for fairer comparisons.
How many housing units did Brookline and the other MMC communities permit relative to their size?
After accounting for each municipality’s relative size, only two communities were on target through 2024: Everett and Revere, which combined permitted nearly 4,600 units above their goal. Despite permitting over 36,000 homes, Boston was on pace for only 71% of its target after accounting for its size. Meanwhile, Brookline produced only 23% of its target, which was lower than all but two communities.
To achieve its equitable target at this point, Brookline would need to authorize an additional 5,800 units from 2025-onward. That’s nearly 1,200 units each year - an unprecedented pace that’s more than 10 times higher than the 105 units it permitted per year between 2015-2024.
But isn’t Brookline already densely populated? Why should it permit housing at the same rate as these other communities?
Although Brookline is more densely populated than much of the state, it’s actually less so compared to many of the MMC communities. Before the MMC initiative began, nine of the 17 communities were more densely populated than Brookline, and of those nine communities, eight permitted housing at a higher rate than Brookline.
Cambridge and Somerville, each more than twice as densely populated as Brookline, permitted housing at a rate approximately 3 times that of Brookline. Everett and Revere permitted at a rate 6-7 times that of Brookline despite already being more densely populated.
Less densely populated communities, like Quincy and Watertown also permitted housing at a higher rate than Brookline.
Whether Brookline is at its desired level of density is a matter for residents to debate, but it’s clear that existing density doesn’t need to impede housing development. Indeed, it appears that many inner metro-Boston communities were able to permit considerably more housing units, in part, because of their density, not in spite of it.
Why isn’t Brookline permitting more housing units?
That’s the million-dollar question. As a participating member of the MMC, Brookline committed to this broader regional housing goal, but it’s unclear whether the town envisioned permitting housing at a rate anywhere near the equitable target calculated here. After all, the collective target wasn’t a binding mandate that the MMC communities needed to comply with (though that does raise the question of which towns were expected to permit more housing, and why).
Differences in zoning bylaws, availability of suitable parcels for development, building costs, and a host of other factors likely play a role in the variation we are seeing across communities. Municipalities have less control over some of these factors than others. Everett, for instance, has considerable industrial land that it’s repurposing for housing and other uses; Brookline and most other communities don’t have parcels at that scale available for development. But zoning bylaws, to the extent they are a barrier to the type of rapid development called for by the MMC’s goal, are within the town’s control to change.
I plan to dive into this issue more in the future, but I will note one piece of information I didn’t touch upon yet: 15 of the 17 MMC communities are cities. The two towns, Brookline and Arlington, permitted housing at the lowest rate of all MMC communities other than Braintree (which just recently approved a 752-unit apartment complex that will drastically increase its performance in this initiative). Does a municipality’s form of government impact its ability to permit housing? That’s a question for future analysis.