Caught Between the Ocean and a Watershed, Designing Climate Change Adaptations for Two Coastal Water Supply Dams in Rhode Island

The North and South Easton Pond Dams are interconnected, raw water supply reservoirs in the City of Newport, Rhode Island. The 12- to 14-foot-high earthen embankment dams, constructed within the footprint of former tidal wetlands in the 1870's and 1890's are classified as High Hazard potential dams, have a combined embankment length of 12,400 feet, and comprise a critical portion of the City of Newport’s long-term water supply. The dams are adjacent to the Atlantic Ocean and are vulnerable to converging risks from extreme inland precipitation, sea level rise, and coastal storm surge.
This paper provides interesting and practical examples of challenges to dam owners from climate change driven flooding, assessment of coastal flooding and sea level rise vulnerabilities, and the identification of potential adaptations to enhance the resiliency of aging dams. The paper is relevant to dam owners and those involved in risk assessment, planning, or design of adaptations to existing dams against future climate driven flooding.