Thompson Island Outward Bound Education Center—Conservation Restriction: Overview


Boston Harbor Islands Partnership

The Boston Harbor Islands were designated as a unit of the National Park Service in 1996.

  • Included all the islands in BHI State Park, and numerous other islands and peninsulas, including Thompson Island

  • Created the Boston Harbor Islands Partnership which stressed the importance of protecting Thompson Island

Thompson Island was the last "unprotected" Boston Harbor Island

  • Continuous educational campus for >160 years

  • Serves thousands of youth annually

  • Part of the BHI National Register Archeological District

  • Diversity of habitats, species, and glacial features


Thompson Island Conservation Restriction

The Conservation Restriction (CR) was purchased for $4 million in June 2002 by the National Park Service and the Commonwealth of Massachusetts.

  • $2 million from the federal Land and Water Conservation Fund

  • $2 million from the 1996 Massachusetts Open Space Bond Bill

The CR includes federal, state, and non-profit partners.

  • The Trust for Public Land helped negotiate transaction and ensure that it is in the public interest.

  • The CR was established in the context of facilitating Thompson Island as part of the Park, and thus it is part of the overall collaborative BHIP effort to preserve the Park's natural and cultural heritage resources and provide opportunities for public enjoyment.

"The permanent conservation of Thompson Island is the crowning achievement in the decades-long effort to clean up the harbor and return it to the people of Boston." - Whitney Hatch, the Trust for Public Land
"This project completes the permanent protection of all of the Boston Harbor Islands. [. . .] This marks the final puzzle piece needed to ensure the overall conservation of these historic and natural resources." - Robert Durand, Massachusetts Secretary of Environmental Affairs

What are Conservation Restrictions?

  • Legal agreement between a landowner (Grantor – Thompson Island Outward Bound Education Center [TIOBEC]) and a qualified holding organization (Grantee – Department of Conservation and Recreation [DCR] and National Park Service [NPS])

  • Permanent interest in a property, recorded at the Registry of Deeds, that protects the important natural resources and conservation values of a property through all subsequent changes in property ownership

  • Allows the landowner to continue to own, use and manage their land but restricts actions that would harm the conservation value of the land

  • Because every property is distinct and individual landowners have different goals for the conservation of their property, each Restriction contains unique terms

CR stewardship includes:

  • monitoring properties to look for any natural or human-made changes

  • enforcing the terms of the CR when necessary


Conservation Restriction Purposes

  • To further the purposes of the Omnibus Park and Public Land Management Act of 1996 establishing the Boston Harbor Islands National Recreation Area;

  • To maintain the significant scenic landscape;

  • To provide important opportunities for public access and recreation;

  • To further the development of educational programs;

  • To protect archaeological resources;

  • To protect important habitats on the Island;

  • To retain the Conservation Area predominantly in its natural, scenic & open condition.

Aerial photograph of Thompson Island. North and South sections outlined in Blue--key denotes these as conservation restriction areas. Central area outlined in red. Key denotes this as building envelope.

DCR/Felicia Bakaj

Thompson Island CR Areas

  • The entire island is subject to the CR

  • Within the CR there are two different areas:

    • Building Envelope (center of the Thompson Island programs and operations)

    • Conservation Area (purposes say this area is to be predominately open & natural)


Reserved Rights/Permitted Uses

  • Reserved rights are the activities and uses that the landowner (TIOBEC) is permitted to carry out under the terms of the CR

  • These rights are reserved for the landowner and whoever they wish to grant them to

  • Permitted uses come with different levels of oversight by the Grantees (DCR & NPS):

    • Allowed with no further requirements

    • Allowed with prior notice

    • Allowed with prior approval

  • The Building Envelope and Conservation Area have different permitted uses with different levels of oversight


Wetland and Archaeological Protection

  • While the CR allows for these activities, it also works to protect the resources.

  • Thompson Island CR does not add any new wetland compliance requirements: all city, state, and federal protections remain.

  • Archaeological resources are further protected by the Thompson Island CR:

    • Prior to undertaking any construction that involves excavation or other ground disturbance, TIOBEC must consult with the State Archeologist at the Massachusetts Historical Commission.

Aerial photograph of Thompson Island. Zoomed in to building area, outlined by red line. Drawing in upper left hand corner shows outline box relative to entire island.

DCR/Felicia Bakaj

Permitted Uses:
Building Envelope


  • Maintain and replace existing structures and facilities
  • Repair, rehabilitate, and restore the exterior of the Hughes (now Salah) and Lewis Gardner buildings in conformance with Secretary of the Interior’s Standards of Rehabilitations
  • Maintain, construct, and install wells, septic systems, and utilities

With Notice:

  • Construct new buildings and structures

Permitted Uses: Entire Conservation Restriction

The uses allowed for the entire Conservation Restriction, including areas outside of the Building Envelope, are much more conservation oriented, which is consistent with allowing for the CR to remain primarily open and natural making.

Thompson Island with the island surrounded by a red border

DCR/Felicia Bakaj


  • Maintenance, modification, and repair of underground utility lines
  • Maintenance, modification, repair, and replacement of educational structures
  • Construction of one major additional educational structure, such as a climbing tower or ropes course
  • Construction and maintenance of trails, signs, and kiosks consistent with Park Area standards, and other minor education and recreation structures
  • Historical agricultural and horticultural uses
  • Selective pruning, cutting, or replanting of vegetation for safety or maintenance
  • Temporary composting of stumps, tree and brush limbs
  • Management of Conservation Area for benefit of wildlife

These additional uses are still permitted across the entire Conservation Restriction area, but given that some of these can be a more intensive or impactful use they require notice or approval prior to beginning them.

With Notice:

  • Construction of up to 4 additional tent platforms, lean-to’s or other similar temporary education structures

With Approval:

  • Relocation or installation of new underground utility lines

  • Reconstruction of the root cellar, and the weather station.

  • Installation of a wind turbine for alternative energy purposes

  • Conducting archaeological investigations

  • Installation of erosion control measures on the steep shoreline bluff in northern portion of Island


Public Access

Because of the unique nature of the Conservation Restriction and the Island, the Department of Conservation and Recreation (DCR), the National Park Service (NPS), and Thompson Island Outward Bound Education Center (TIOBEC) have spent significant time considering and negotiating public access. These designated access areas are reflective of the dedication of the partners to balance public access, the rights of TIOBEC to run its operations and facilities, and the protection of the resources.

Three types of public access are defined by the CR:

1) “Unescorted Public Access” (UPA): Members of the public can have access to the Conservation Area, shoreline and beaches for low-impact, non-motorized, non-commercial outdoor recreational use as defined in the Access Plan under the following conditions:

  • They have UPA Reservations (reservation on a specific day on which UPA is authorized)

  • They enter the Premises from a scheduled UPA Ferry (boat authorized by Thompson to drop off and pick up UPA visitors)

  • They receive orientation from Thompson staff upon arrival and acknowledge agreement to follow applicable rules and practices

2) “Beach Access”: Access by members of the public from individually owned private boats to, and only to, the beaches at the perimeter to the Premises (no access to uplands).

3) “Escorted Public Access”: organized groups of members of the public that are actively supervised during their stay on the Island as approved by TIOBEC

Aerial photograph of Thompson Island. Various colors used to denote boundaries of conservation, building envelope, no public access, unescorted public access, and beach access areas.
This map of Thompson Island uses color overlays and borders to denote boundaries of conservation, building envelope, differing levels of public access, and CR designated "sensitive" areas.

DCR/Felicia Bakaj

Public Access Plan

  • The terms of public access to the island are further defined in a Public Access Plan (CR Exhibit B).

  • The Access Plan can be modified by mutual agreement

  • The island remains private property; owners have a right to protect their property and staff

  • The owners have the right to close the island to the public in the case of health and safety concerns

Public Access from the ‘Spit’

  • The CR states that there is no allowable Unescorted Public Access to the island from the spit that connects the island to Squantum at low tides

  • Beach Access includes the spit (i.e. access by private boat, to the beach only)

  • Public Trust Rights/Colonial Ordinances are separate from the CR and not administered by the Grantees (DCR and NPS)


Conservation Restriction Stewardship

  • DCR and NPS formally monitored the property in 2005, 2012, 2016 and 2019

  • An ad hoc site visit was made in September 2020 among DCR, NPS, the BHIP chairperson, and TIOBEC due to recent concerns about public access

  • We collectively resolved to:

    • Make the signage on the island perimeter more welcoming and informative, with information about the CR, how the public can access the island, visitor amenities and the rules for public visitors

    • Make sure the Conservation Restriction and public access information is more readily available

We look forward to working in partnership to continue protecting this amazing ecological and educational site and to retain the values that have changed young people’s lives for the past century to ensure they do so for the next century as well.

Last updated: May 11, 2021

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Charlestown, MA 02129


617 223-8666

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