Robust Stormwater Strategies under Climate Change: A Case Study in Somerville, Massachusetts.
management systems involve many challenges including flooding and associated property
damage, combined sewer overflows, and poor water quality in surface waters. All these
may be exacerbated under a changing climate in the future. This study uses a detailed
methodology to identify robust adaptation strategies for managing urban stormwater under
climate change uncertainty.... read moreRobust strategies are strategies that function acceptably
well under all future uncertainties and risks. The objective of this study is to
investigate effective responses for urban water managers to the challenges of drainage
management in conditions of a changing climate through a new methodology. Robust
adaptation strategies are evaluated for a combined sewer system in Somerville,
Massachusetts using the U.S. EPA Storm Water Management Model (SWMM). Various design
storms are simulated in 2010, 2040, and 2070 under low, moderate, and high climate
change scenarios. Five strategies for stormwater/CSO management are tested under these
conditions to find a strategy which performs well under all conditions considered, which
we term a robust strategy. Two decision-making approaches are used to quantify results:
a design cost approach and a net benefits approach. Both approaches utilize risk
analysis for each climate change scenario to determine the expected values of costs, and
in the case of net benefits, the benefits of management. Costs to meet design criteria
are compared for each climate change scenario to identify the most cost-effective robust
strategy. Similarly, net benefits are compared and the most beneficial robust strategy
is identified. This methodology identifies sewer separation as the best robust strategy
under both approaches.
Thesis (M.S.)--Tufts University, 2011.
Submitted to the Dept. of Civil Engineering.
Advisors: Richard Vogel, and Paul Kirshen.
Committee: Paul Mathisen.
Keyword: Environmental engineering.read less