The Massachusetts Tideland Development Calculator

The Massachusetts Public Waterfront Act (also known as “Chapter 91”) gives Massachusetts residents a legal right to access waterfront areas called tidelands.

The Massachusetts Tideland Development Calculator is designed to demonstrate the tradeoffs between waterfront development and the public’s waterfront access rights.

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Conservation Law Foundation developed this calculator in partnership with HR&A Advisors with support from the Barr Foundation.

During the municipal harbor planning process, in specific situations when a waterfront development project is permitted to deviate from the rules that help ensure public access and benefit, the project owner must compensate the public financially. This calculator demonstrates a reasonable way of estimating that compensation.

You can use this tool to estimate the value of a proposed waterfront project and compare it with the value of a project that abides by Public Waterfront Act rules. When a proposed project limits public access onsite and increases its value, the project benefits from a value premium. And this value premium can be a source of compensation back to the public in return for limiting their rights.

View of the Boston waterfront from above
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Basic Inputs

Complete these inputs to describe basic site conditions and market conditions for your proposed project and the comparison project. Basic inputs include whether the site is on Commonwealth tidelands or private tidelands, which have different levels of requirements for protecting public access rights.

SF

The model automatically follows default Public Waterfront Act height regulations. Buildings within 100 FT of shoreline are limited to 55 FT in height. Beyond 100 FT of the shoreline, building height may increase 1 FT per every 2 FT of distance further inland. The following optional inputs affect these height calculations.

FT
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Project Assumptions

Use this section to define the different real estate uses (e.g. housing, retail, office space) that your project includes, as well as the construction styles of your project.

The “program” of uses in your project will define building costs overall value. Different uses entail significantly different development costs per square foot, and significantly different revenue levels and project values. Parking styles also differ substantially in development costs per square foot, with underground parking being the most expensive.

  • A proposed project could be a real proposed project, or a project you create on your own.
  • The comparison project is a project that has the same proportional uses as the proposed project, but strictly conforms to to Public Waterfront Act requirements based on the size of the parcel and its relationship to the shoreline.

Real Estate Assumptions

Proposed Project Assumptions

Please select a city and market context in the Basic Inputs section above.

Comparison Project Assumptions

Please select a city and market context in the Basic Inputs section above.

Onsite Infrastructure

Note: Recommended for advanced users only.

Manually enter costs related to onsite infrastructure, including parking, shoreline and seawall infrastructure, marine construction, and other site infrastructure. Alternatively, can use a menu of pre-filled common infrastructure line items to specify a basic infrastructure program.

*Disclaimer: Preloaded infrastructure cost estimates are ballpark figures that are incomplete in scope and cannot address the unique technical requirements of a given site or project. A user seeking exact infrastructure development costs should consult a professional engineering firm.

Only use this section for infrastructural elements that exceed whatever is mandated by existing environmental regulations.

Results

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Fill in all relevant inputs in the calculator and click "View Results"

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Disclaimers

  • When simulating the legally achievable scale of development for the “comparison project,” the tool is only taking into account Public Waterfront Act requirements. The simulation does not account for any other building code, coastal development, or other local policies that may affect the dimensions or uses of real estate. The simulation also does not account for the impact of water-dependent use zones (WDUZ) and associated requirements.
  • This tool generates ballpark valuation estimates using credible regional market assumptions and discounted cash flow calculations based on real estate industry best practices. The tools outputs are not exact.
  • The tool will generate a result based on the inputs entered by the user. If the user selects a development program or other inputs that are unrealistic or unfeasible, the tool will generate a result that could be inaccurate or unrealistic.
  • The tool is designed to model the development of single buildings on individual lots of land. Large development projects that span multiple parcels of land should be modelled on a parcel-by-parcel basis.
  • Preloaded infrastructure cost estimates are ballpark figures that are incomplete in scope and cannot address the unique technical requirements of a given site or project. A user seeking exact infrastructure development costs should consult a professional engineering firm.
  • This tool should not be used for projects in Designated Port Areas (DPAs), which have separate rules and requirements that are not accounted for in this tool.
  • The tool is not meant to evaluate other forms of public benefit, including but not limited to affordable housing, the mitigation of flooding and storm surges, or public park programming.