New Research Supports Regional Trend: Supply of Off-Street Residential Parking Outweighs the Demand
A more “perfect fit” of parking supply and demand can lower development costs, enable more affordable housing, free up land for open space, and promote sustainable transportation
July 17, 2023 – BOSTON – The Metropolitan Area Planning Council (MAPC) has expanded its Perfect Fit Parking research to include municipalities west of Boston, adding another contribution to an increasingly robust dataset that highlights how most communities have built more residential off-street parking than is needed or utilized. These results will inform how municipalities can sustainably update their zoning in response to the state’s Multi-Family Zoning Requirement for MBTA communities.
MAPC was approached by the WestMetro HOME Consortium in 2021 to conduct the Phase 4 parking utilization study at multifamily housing developments in the Consortium’s member municipalities west of Boston. Thirty-six multifamily sites across Brookline, Concord, Needham, Newton, Sudbury, and Watertown were both surveyed for building characteristics and observed overnight on weeknights for peak parking counts in 2022.
While the parking supply, demand, and utilization varied across the six municipalities studied, the Phase 4 analysis showed that overall, 39% of the off-street parking spaces were not utilized during peak hours. This is an even higher percentage than was observed during the first three phases of the Perfect Fit Parking research. The Phase 4 study further found that, consistent with the previous research, parking supply was the single largest factor associated with parking demand – the more spaces provided, the more cars were parked, all other things being equal.
“In every municipality and at every development, parking was oversupplied,” said Adi Nochur, senior transportation planner at MAPC. “Municipalities with the most parking per unit had the lowest utilization, meaning developers had to build hundreds of parking spaces that are not needed. This drives up housing and development costs, lowers housing production, and contributes to increased automobile usage and greenhouse gas emissions right when we are in the middle of housing and climate crises.”
The Phase 4 study found an average of 1.58 parking spaces supplied per unit, but only an average of 1 parking space demanded per unit. Good transit access to jobs and the presence of deed-restricted affordable units were both associated with reduced parking demand. All these findings are consistent with previous phases of MAPC’s Perfect Fit Parking research. This discrepancy further highlights that parking is overbuilt at the Phase 4 sites studied, to the detriment of providing more housing units (including more affordable units), improved transit access, and increased open space.
“Watertown is excited to get hard data on utilization to inform public conversation about the amount of parking we require for multifamily housing,” said Steven Magoon, assistant city manager for the Town of Watertown. “This is perfect timing for such a conversation, as our draft comprehensive plan released three weeks ago recommends that we review the city’s parking requirements, and this helps us make sure that projects don’t have too much or too little parking.”
MAPC’s began its Perfect Fit Parking research in 2015 to equip local planners with detailed and accurate information so they can make informed decisions about parking plans and policies. National trends indicate that more urban residents are forgoing vehicle ownership in favor of more sustainable practices, but parking requirements have generally stayed the same.
“Multifamily housing sites in suburban locations may have higher parking demand than sites in more transit-accessible locations, like MAPC’s Inner Core,” said Nochur. “However, the parking utilization research, now including this Phase 4 study, has consistently found that parking is oversupplied at sites throughout Greater Boston – whether urban or suburban.”
To right-size parking in line with affordable housing and transit goals, MAPC recommends that the WestMetro HOME Consortium member municipalities adhere to the same policy prescriptions noted in earlier phases of the Perfect Fit Parking research, including:
- shifting from parking minimums to maximums;
- reducing parking ratios;
- unbundling parking from housing costs;
- exploring strategies for shared parking.
The most recent Phase 4 parking study, as well as MAPC’s studies from previous parking research, can be viewed at perfectfitparking.mapc.org.
Senior Communications Specialist