Session B2 - Critical Linkages: Assessing Connectivity Restoration Potential for Culvert Replacement and Dam Removal in Massachusetts

The University of Massachusetts Amherst, working in partnership with The Nature Conservancy and state agencies, integrated data related to landscape connectivity and human development, and completed a comprehensive analysis of areas in Massachusetts where aquatic connectivity can best be enhanced by culvert replacement and dam removal. The Critical Linkages project builds on the existing Conservation Assessment and Prioritization System (CAPS), a computer model developed by UMass that incorporates biophysical and anthropogenic data to compute an index of ecological integrity (IEI). Because CAPS provides a quantitative assessment for IEI as well as each metric used in ecological integrity models it can be used for comparing various scenarios. Scenario analysis involves running CAPS separately for each scenario, and comparing results to determine the loss (or gain) in IEI or specific metric units. In Phase 1 of the Critical Linkages project we used the scenario testing capabilities of CAPS to assess changes in the aquatic connectedness metric for dam removal and culvert/bridge replacement projects. A baseline assessment of aquatic connectedness provided a statewide base scenario for comparison of restoration options. Scenario-testing software was developed to efficiently assess restoration potential for large numbers of possible restoration projects and then applied statewide to road-stream crossings and dams. Results of these analyses indicate that a relatively small proportion of culvert replacement and dam removal projects would result in substantial improvements in aquatic connectivity