Water Resources Collections and Archives

Many dams built over the last century in California no longer provide their intended benefits and may pose ecological and safety risks. However, a lack of clear regulatory framework, further complicated by a lack of scientific understanding of the impacts of dam removal, has handicapped many efforts to remove such outmoded dams. We investigate these challenges through a case study of York Creek Dam in St. Helena, California and show the need for standard protocols to prioritize and monitor dam removals. As a thought experiment, we explore how dam removal would proceed under the European Union Water Framework Directive (WFD) and argue that California can learn from the WFD’s systematic, watershed approach to improve dam removal decision-making. However, the monitoring programs under the WFD are driven by ecology and therefore provide little guidance on monitoring channel changes to evaluate whether dam removal increases the risk of flooding for downstream property, a major concern in California.