The comprehensive development of green spaces and wildlife corridors in Boston is expected to cost a total of $15.2 million, distributed across four project sites in the city. The first target area is Sprague Pond, where water quality monitoring and stormwater drainage education efforts will be implemented. The Terrascope Class of 2024 proposal for restoration in Sprague Pond does not include construction or physical development, and there are thus no calculated additional costs of implementation. Target area two involves reclamation of the West Roxbury Quarry and development of additional wildlife corridors, which will comprise $8.4 million based on scaling of the costs associated with previous similar projects. Park construction associated with target area three will cost a total of $5.2 million, while wildlife corridor extensions in target area four will cost a projected $1.6 million.

Target Area 1: Sprague Pond

Sprague Pond is located adjacent to the Neponset River, where organizations such as the NepWRA CWMN are currently monitoring water quality at various sites.[1] The Terrascope Class of 2024 proposal follows a similar model, in which local environmental organizations or volunteers would conduct water quality testing at Sprague Pond. Similarly, the stormwater management outreach program relies upon collaboration between the town and local environmental groups, which would conduct educational efforts.[2] It is projected that volunteers and nonprofit organizations would be the most effective agents to carry out both the water quality monitoring effort and the outreach to local residents and landowners. Based on these proposals and the absence of construction or physical development in this target area, there is no additional calculated cost of implementation for the Sprague Pond restoration project.

Target Area 2: West Roxbury Quarry and Wildlife Corridors

Within this target area, there are two main solutions proposed: (1) reclamation and restoration of the West Roxbury Quarry and (2) construction of adjacent wildlife corridors along Grove St. and Lagrange St.

Reclamation of the West Roxbury Quarry involves filling the quarry, conducting revegetation with native plant species, then following through with long-term monitoring of the site to ensure that wildlife restoration is successful. Reclamation of any quarry generally involves similar processes, with expenses associated with the equipment and manpower needed to fill the quarry, as well as with the more long-term revegetation and monitoring.

A Financial Assurance Cost Estimate was developed in 2014 for Permanente Quarry, a stone quarry located in California.[3] Permanente Quarry has notable structural similarities to West Roxbury Quarry, but is larger in scale, encompassing 900 acres in comparison with the West Roxbury Quarry’s 60 acres.[4],[5] The two quarries are also similarly surrounded by undeveloped wooded space, with natural habitats that should be restored over the quarry sites. The Financial Assurance Cost Estimate includes both direct and indirect costs, and accounts for the removal of structures, site grading, revegetation, monitoring, and maintenance.[6] The vast majority of these costs are dependent on and determined by the size of the quarry site. The full cost estimate report includes a breakdown of costs and demonstrates that the majority of direct costs are calculated based on hourly costs. It is fair to assume that less hours would be spent filling a quarry of smaller size, and that the time required would be relatively proportional to quarry size. Hence, the cost estimate given for Permanente Quarry was scaled in terms of the acreage and time investment required for West Roxbury Quarry in order to produce a final cost of about $3.2 million.[7]

Secondly, the costs associated with developing wildlife corridors along Grove St. and Lagrange St. were calculated. The planning of this project is expected to fall under an objective listed in Boston City’s Open Space and Recreation Plan for 2015-2021, which calls for the expansion of parkway links connecting pre-existing parks.[8] Based on the allocation of this project under the Boston Department of Parks and Recreation, it can be assumed that the city government will partner with similar groups to construct these wildlife corridors as they have in the past for other wildlife corridors. Specifically, the Massachusetts Port Authority (Massport) completed construction of the Greenway corridor in Boston in 2014.[9] This Greenway corridor is similar in function, planning, and construction to the intended corridors along Grove St. and Lagrange St. Cost estimates for the Greenway corridor are also extremely relevant to the wildlife corridor construction methods used in the present day, as this corridor’s construction occurred very recently. Finally, the Terrascope Class of 2024 is prepared to assume that Massport or a similar contractor would be hired to plan and construct the proposed new wildlife corridors, which indicates that the associated project costs would likely be similar to those of the Greenway.

The Greenway path is approximately half a mile in length and occupies a total area of 5.22 acres.[10] This project group’s proposed parkways would encompass 0.9 miles along Grove St. and 0.7 miles along Lagrange St. Estimating the width of each proposed corridor to be approximately 20 feet (in comparison with 12 feet in the Greenway corridor), the total area of the project site would be 3.9 acres. Based on a projection of costs proportional to the cost of Greenway development, these wildlife corridors would in sum cost an estimated $5.2 million dollars.[11]

Hence, the total costs associated with target area two are projected to equal $8.4 million.

Target Area 3: Park Expansions in the Mattapan Neighborhood

The third target area focuses on park expansions in the Mattapan neighborhood, as called for in the Boston City Open Space and Recreation Plan.[12] Specifically, the Terrascope Class of 2024 focused on development of one specific park adjacent to Harbor Health Services and Manchester St. This park will occupy a currently empty lot, meaning that no displacement will occur as a result of the project. This park represents a case study for the development of green spaces in the neighborhood, and similar processes will likely need to be followed in order to generally increase community access to nature.

Generally, it is estimated that construction costs for a moderate-activity urban park in Boston will equal about $2.6 million per acre, including softscaping, hardscaping, and development of facilities.[13] The proposed park next to Harbor Health Services will be surrounded primarily by residential areas, but is near a few busier roads. It is expected to become a moderate-activity urban park due to the proximity of residential areas and based on activity levels observed in the nearby Dorchester park.

This project site includes a total of about 2 acres of undeveloped land. The construction cost estimate of $2.6 million per acre can be used to provide a projected cost estimate of $5.2 million for the development of a park in the Mattapan neighborhood.[14]

Target Area 4: Extension of the Southwest Corridor Park & South Bay Harbor Trail

Finally, the last target area involves the extension of an existing wildlife corridor, the South Bay Harbor Trail. Construction of this wildlife corridor is expected to follow similar practices and methodologies to those used in target area two. Therefore, similar practices were followed in order to estimate the cost of this wildlife corridor expansion. The corridor would be constructed along Massachusetts Avenue for a total of 0.5 miles, resulting in a project site of about 1.2 acres. Following the metric described above, this extension of the South Bay Harbor Trail should cost about $1.6 million.[15]

Beyond the direct costs of construction, it is anticipated that there may be more indirect costs associated with this wildlife corridor than with the corridors along Grove St. and Lagrange St. Massachusetts Avenue is known to be a busy and well-used road, and obtaining community support for construction, as well as preventing extensive traffic during construction, may result in additional indirect costs.

Furthermore, while the Terrascope Class of 2024 is not explicitly outlining proposals for park expansions in this target area, the class strongly supports the Boston Open Space and Recreation Plan intentions to develop new parks in the area west of Massachusetts Avenue. Disjointed parks scattered throughout the area can still serve as a stepping stone wildlife corridor, and the development of parks and green spaces is a solution which greatly complements the construction of wildlife corridors.[16]


[1] Citizen Water Monitoring Network. (2020, November). Neponset River Watershed Association. 

[2] Regional SWMP For Public Outreach and Education. (2019). Neponset Stormwater Partnership.

[3] EnviroMINE. (2014, January). Financial Assurance Cost Estimate for Permanente Quarry. County of Santa Clara.

[4] Cupertino City Hall. (n.d.). LEHIGH INFORMATION. City of Cupertino. 

[5] Boston Parks & Recreation. (2015, January). Open Space & Recreation Plan 2015-2021. City of Boston. 

[6] EnviroMINE. (2014, January). Financial Assurance Cost Estimate for Permanente Quarry. County of Santa Clara.

[7] Ibid.

[8] Boston Parks & Recreation. (2015, January). Open Space & Recreation Plan 2015-2021. City of Boston.

[9] Massport. (2014, August 21). Massport Celebrates Opening of Greenway Connector in East Boston. Massport Newsroom.

[10] Ibid.

[11] Ibid.

[12] Boston Parks & Recreation. (2015, January). Open Space & Recreation Plan 2015-2021. City of Boston.


[14] Ibid.

[15] Massport. (2014, August 21). Massport Celebrates Opening of Greenway Connector in East Boston. Massport Newsroom.

[16] Boston Parks & Recreation. (2015, January). Open Space & Recreation Plan 2015-2021. City of Boston.