2 Analysis of Harbor-Wide Barrier Systems

Analysis of Harbor-Wide Barrier Systems / University of Massachusetts

The Sustainable Solutions Lab at the University of Massachusetts Boston used a scenario-based approach to analyze the feasibility and potential risk reduction of Boston Harbor barrier systems to protect the Boston area from future flooding due to sea level rise. The report included an economic analysis in which costs and benefits were predicted for 32 scenarios considering:

  • Two barrier system alternatives
  • Two construction time scenarios
  • Two scenarios for effectiveness of “shore-based solutions”
  • Low and high construction cost estimates
  • Discount rates of 3% and 7%

The analysis indicated that the benefits of the proposed barrier system would exceed their cost for both systems evaluated, but only in the case that one assumed a low discount rate, accelerated construction schedule, and failure of other shore-based solutions for mitigating sea level rise. Also, the analysis indicated that beyond a certain point sea level rise would be such that a barrier system would no longer prove effective (since the barrier would have to be closed at all times rather than only during flood events). The report further predicted costs and benefits for two alternative scenarios involving incremental adoption of a variety of shore-based mitigation approaches, and recommended an initial focus on shore-based adaptation as the most promising strategy for the City of Boston to address sea level rise.

Source: https://www.greenribboncommission.org/wp-content/uploads/2018/05/Feasibility-of-Harbor-wide-Barriers-Report.pdf

Read more in the chapter: 5.1.4 Consideration of Risk in Resource Allocation