Gina Sonder has written a great plan-language explainer of what the recent state law known as “MBTA Communities” is all about, and how the law affects Arlington. Reprinted here with helpful links added by permission.

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

What Is This New State Law?

Along with 176 other towns and cities in the Boston-Metro region with MBTA service, Arlington is mandated by the State to create a plan that would allow property owners to build midsize housing without the need to first apply for and be granted a special “Multi-Family” or “Townhouse” or “Apartment Building” permit.

This mandate, the MBTA 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 to buildings containing 3 or more Dwelling Units (DUs). For the purpose of MBTA-C, these units must be a mix of configurations and sizes (ie: studios, 1,2,3+ bedroom apartments, condos, townhouses.) The law aims to increase housing choice for all ages, abilities, and family sizes, near public transit.

What Must Towns Do?

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 MBTA-C 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 of multi-family housing on that designated land. Nothing actually needs to be built within a set time-frame 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. Because Arlington is a fully built up town, without undeveloped parcels of land for 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 with 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.

How Does The Law Affect Housing Affordability?

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) 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 of housing stock and affordable units set at a 1 in 10 ratio per project, the current law does not address affordability in a meaningful way for our neighborhoods. Only large lots on Mass Ave and Broadway could be built with 10 or more units to trigger the requirement for affordable units. In addition, the MBTA-C threshold for renters and buyers is for persons making 80% Area Median Income (AMI).

Arlington’s own Zoning ByLaws are already more inclusive than state guidelines; Arlington requires 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 District to match the Town’s own 15% ratio. Until changes are approved by the State, Arlington can only require affordable units be supplied at the State’s 10% ratio.

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

What Else Can Arlington Do About Housing? Opinion by Gina Sonder

The MBTA-C mandate is just one way Arlington can increase housing options.

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 constrained by MBTA-C rules. The Town can choose to go far beyond the mandate and create truly inclusionary zoning outside of the MBTA-C Districts.

Our own Zoning ByLaws are locally enforceable and can achieve our desired goals. Arlington’s housing development would be responsive to the needs of the community, not the State, and would be subject to Town requirements and plan review.

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 modest plan that meets compliance requirements, benefit from the programs eligible to towns that pass Town Meeting this year, and move ahead to focus on updating its own missing middle Zoning Bylaws to achieve the welcoming sustainable community we all desire.

Above text by Gina Sonder, reprinted with permission

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