Arlington's MBTA Communities mandate

MBTA Communities and what it means – an explainer for Arlington Residents

by Gina Sonder, Arlington Resident and Architect

Along with 176 other towns and cities in the Boston-Metro region that have MBTA service, Arlington is mandated by the State to create a plan that would allow property-owners to build residences which contains three or more dwelling units, without the need to first apply for and be granted a special “Multi-Family” or “Town House” or Apartment Building” permit.

This mandate, the Metro-Boston Transit Authority Communities Zoning Law for Multi-Family Residential Districts under Massachusetts General Law Chapter 40 Section 3(A) has been abbreviated to “MBTA-C” in this document.

The State defines “Multi-Family Residential” housing as building containing 3 or more dwelling units{DUs.] For the purpose of MBTA-C, these units must be a mix of various configurations and sizes (ie: studios, 1,2,3+ bedroom apartments or condos or townhouses.) The law aims to increase housing choice for all ages, abilities, and family sizes, near public transit.

Towns are tasked with creating a designated area or district where Multi-Family housing would be allowed, without the need for a special permit. The area could be a single district or several sub-districts. The guidelines require 50% of the zoned area and buildable units to be in a single District. Sub-districts must be at least 5 acres.

Arlington is required to identify and designate a minimum of 32 acres, averaging a minimum of 15 dwellings per-acre, with the ability to develop a minimum of 2046 units [DU’s]* of multi-family housing on that designated land. Nothing actually needs to be built within a set timeframe to comply with the law.

This stipulated 2046 DU number is not added to the houses currently existing on lots, but a theoretical model of what could be built on those lots if owners choose to add or replace what exists in the future. Because Arlington is a fully built up town, without undeveloped parcels of land to locate an MBTA-C zone, the DU “capacity” represents the size and amount of building allowed as if the designated lots were vacant.

For example, if the Town designates a district currently occupied by 2000 dwellings and zones it for a capacity of 7000 DUs (+3x compliance,) if fully developed sometime in the future, the net result would be an additional 5000 dwelling units in that district.

The MBTA-C mandate aims to address housing choice in what is called the “missing middle,” buildings like triple deckers, townhouses, 4-plexes, courtyard buildings which are the category between large apartment buildings and single and two family residences. MBTA-C gives owners the ability to build this type of midsize housing “by-right,” without the need for a special permit.

Although affordability is a stated aim, the MBTA-C law is not an affordable housing production plan. With increased supply and affordable units at a 1 in 10 ratio per project, the law does not currently address affordability in a meaningful way for our residential neighborhoods. Only large lots on Mass Ave and Broadway could be built with 10 or more units and trigger the requirement for affordable units, and the MBTA-C threshold for renters and buyers is for persons making 80% Area Median Income [AMI.]

Arlington’s own Zoning ByLaws are more inclusive, requiring that 15% of units (1 in 6 units) be affordable to renters making 60% AMI and buyers making 70-80% AMI.

Arlington will be submitting an economic feasibility study to the State (EOHED) seeking the ability to increase the affordability ratio in our MBTA-C Zones to match the Town’s own 15% ratio. Until approved by the State, Arlington can only require affordable units be supplied at the State’s 10% ratio.

The zones designated for MBTA-C Housing are not fully under local control.

The MBTA-C towns must adhere to the guidelines developed by the State’s Executive Office of Housing and Livable Communities [EOHLC] (formerly Massachusetts Department of Housing and Community Development [DHCD].) These guidelines are new and subject to change over time as more towns develop their plans and the region sees the results in the Metro-Boston communities.

The MBTA-C mandate is just one way Arlington can increase housing options for those seeking to live close to Boston or stay in Town.

The Town of Arlington can develop and revise its own Zoning ByLaws to increase multi-family homes and a vibrant business district in tandem with the required MBTA-C overlay districts to fulfill our housing choice and sustainability goals. Arlington’s Zoning Bylaws are not limited to the MBTA-C rules. The Town may decide when, what, and where housing stock can be built now and in the future, above and beyond the State's mandated requirements.

By updating Arlington’s town Zoning Bylaws, developers outside of the MBTA-C district would be subject to our own requirements and plan review. Our own Zoning ByLaws are locally enforceable and can go further than the State’s mandate to achieve our desired goals. Arlington’s housing development would be responsive to the needs of the community, not the State.

While the Town needs to comply with MBTA-C under its current guidelines, to become the more inclusive, more affordable, more sustainable, and more business-friendly town that a majority of citizens want, this author believes that Arlington should pass a plan that meets compliance requirements and move ahead to focus on updating its own missing middle Zoning Bylaws.

*Stipulated by the State, 2046 dwelling units [DU’s] is 10% of Arlington’s housing stock per the 2020 census.