damremoval

Dam removal refers to the deliberate dismantling or breaching of a dam to restore a river's natural flow and connectivity. It is pursued for safety concerns, aging or uneconomic infrastructure, environmental restoration, and flood or water-management objectives. Removal typically involves decommissioning, sediment management, and site rehabilitation to accommodate downstream geomorphology and habitat recovery.

Planning begins with an assessment of structural integrity, downstream risk, and potential environmental impacts. Regulators, dam owners, Indigenous and local communities, and scientists participate in feasibility studies and environmental analyses. Removal may be complete or partial, and often requires dewatering, controlled breaching, and stabilization work. Sediment management may include staged release, dredging, trapping, or capping contaminated sediments, followed by site restoration.

Environmental and social effects include restored fish passage and river connectivity, reconnected floodplains, and improved ecological function. Potential drawbacks include the release of accumulated sediments and contaminants, temporary increases in turbidity, downstream erosion, disruption to water users, and the loss of hydropower capacity. Careful sequencing, monitoring, and adaptive management help address these risks.

Notable examples include the Elwha River in Washington, where two large dams were removed between 2011 and 2014 to restore salmon runs and river continuity. Across regions, numerous smaller dams have been removed to advance river restoration goals. Funding and approvals typically involve federal, state or provincial agencies, local governments, non-profit groups, and the dam owner, with stakeholder consultation throughout the process.