SHADOW LEGISLATION
Two State laws in place for the past quarter of a century have effectively protected Boston’s signature public parks from excessive shadowing, while still allowing for robust downtown development. One of the Friends most challenging advocacy efforts to date centered on the Shadow Laws in 2017 when the City of Boston filed a Home Rule Petition to exempt the proposed Millennium Tower at Winthrop Square in the Financial District. Though unsuccessful in preventing the exemption, the Friends of the Public Garden continues its steadfast commitment to support these effective laws and opposes any further erosion of these critical protections.
Following is a summary of the current State Laws:
(Ch. 362, Acts of 1990; Ch. 384, Acts of 1992; Ch. 57, Acts of 2017)
This State law restricts new shadows on the Common to the first hour after sunrise or 7:00 a.m. (whichever is later) or the last hour before sunset, with different restrictions for buildings in the Midtown Cultural District, which lies east and south of the Common and Garden.
For buildings in the Midtown Cultural District, new shadows are allowed for no more than two hours between the hours of 8:00 am and 2:30 pm from March 21 to October 21. Any new shadow lasting two hours or more during these times is not allowed.
(Ch. 384, Acts of 1993; CH. 57, Acts of 2017)
This law restricts new shadows on the Public Garden to the first hour after sunrise or 7:00 a.m. (whichever is later) or the last hour before sunset.
For buildings in the Midtown Cultural District, new shadows are allowed before 10:00 a.m. during the period between March 21 and October 21.
A zoning ordinance adopted by the City of Boston in 1989 provides additional protection for the Boston Common and Public Garden from excessive shade by setting a height limit of 155’ throughout the Midtown Cultural District. The Midtown Cultural District is the area abutting the Boston Common and Public Garden from Arlington to School Streets and generally defined by Boylston, Tremont, and Washington Streets.
In addition, it created a special Protection Area within the District – the Boston Common and Public Garden Protection Area – for buildings along Tremont and Boylston Streets. Height limits in this Area range from 125’ – 155’ along Tremont Street and from 85’ – 130’ along Boylston Street.
The Downtown Zoning Amendment that was passed by the BPDA Board in September 2025 effectively dissolves the Midtown Cultural District, but retains certain shadow exemptions for future development projects. See below for more detailed information about the Friends concerns related to the Downtown Zoning.
Before the shadow laws were passed, the BRA established the Midtown Cultural District in Article 38 of the zoning code (in 1989). Article 38 helped facilitate redevelopment of the Theatre District and provided protections for historic buildings among other considerations.
When the State Shadow Laws were established in 1990 and 1992, the Midtown Cultural District was referenced in those laws and granted certain exemptions from the established shadow limits in the laws. The laws generally only allow new shadows on the Boston Common and Public Garden during the first hour after sunrise and last hour before sunset. However, within the Midtown Cultural District, new projects are allowed to add up to 2 hours of new shadow to the Boston Common between 8 am and 2:30 pm on any day between March 21st and Oct 21st, and unlimited shadows are allowed outside of those times. New shadow is allowed on the Public Garden before 10 am during those same March – Oct dates.
Zoning at the time (and until now) only allowed buildings in the Midtown Cultural District to be 155′ tall. This has meant that while these exemptions for new shadows have existed for the past 35 years, building heights close to the parks were low enough that we weren’t seeing a lot of projects that took full advantage of the 2-hour shadow allowance. In addition, the new zoning proposes to remove the “Boston Common and Public Garden Protection Areas” which were defined in Article 38 Section 5 and set height restrictions along the edges of both the Common and the Public Garden.
Now, with this new zoning as proposed, buildings can be 500 feet or taller as of right in parts of this same Midtown Cultural District area. If this zoning passes, the Friends of the Public Garden is concerned that it will open the door to more projects being proposed that will each introduce new shadow to the parks that last for up to 2 hours between 8am and 2:30 pm, and may extend for any number of hours after 2:30 pm. Because the 2-hour shadow limits are set for the March 21 – Oct 21 time of year, it means that from Oct 22 – March 20 every year, any project can exceed these shadow limits. Access to sunshine during the shoulder seasons and colder months, while not the growing season, is crucial for making the city’s public realm inviting for human use.
The sunshine modeling that the Friends has done through an architect and urban designer at MIT illustrates the difference of building heights that are allowed under the baseline shadow laws and how much taller they can be thanks to the Midtown Cultural District exemptions. The Friends is looking closely at the zoning language and our sunshine model so that we have a clear understanding of what is expected in the future. Our understanding of the zoning is that it grants developers the maximum building heights – inclusive of the Midtown Cultural District exemptions – as of right, instead of holding them to the baseline heights that the Shadow Laws allow. If the zoning set building heights at the baseline Shadow Law limits, then greater heights could be evaluated based on the actual location and duration of additional shadows and granted on a case-by-case basis. If the City took this approach, it would go a long way in buffering the potential adverse impacts of the Midtown Cultural District exemptions.
On top of this, the zoning dissolves the Midtown Cultural District but keeps the exemptions it grants. If the City no longer recognizes the Midtown Cultural District as a meaningful geography from a planning perspective, why are we still carrying forward the shadow allowances that were granted for this area 35 years later?