Connecticut Department of Energy & Environmental Protection

DEEP headquarters at 79 Elm Street in Hartford has partially re-opened to staff and members of the public as of Tuesday, February 3. The DEEP records room has re-opened. The DEEP Central Permit Processing Unit (CPPU) will be open to the public starting on Wednesday, Feb. 4. For updates, click here

Benefits of Dam Removal

The removal of a dam can have numerous advantages, including the reduction of downstream hazard, reduction of the dam owner’s liability, environmental enhancements, and improvements to public safety. If the impounded water is no longer serving any purposes and the dam owners wish to eliminate the liability and risk a dam presents, removal should be evaluated.

 A restored reach of Steele Brook in Watertown following the removal of Heminway Dam
Reduction of Downstream Hazard

The water that's stored behind a dam can become a serious hazard if that dam fails. Dam failure can cause damage to property and infrastructure, economic loss, and harm to downstream inhabitants. When a dam is fully or partially removed, the volume of water that it can impound (and the associated consequences) is reduced.

Reduction of Dam Owner's Obligations

When a dam is removed and its downstream risk is eliminated, the liability of the dam owner will also likely be eliminated. Because damage can no longer occur due to the dam (either upstream or downstream), dam owners may eliminate the possibility of incurring penalties. Also, if the downstream hazard is eliminated, dam owners should be able to avoid the cost of inspections, repairs, and other activities required by dam owners.

Ecological Enhancements

Dam removal can improve ecological conditions in many ways: 

  • Allows for the upstream and downstream passage of fish and other aquatic organisms, like freshwater mussels. This improved connectivity improves their ability to migrate, reproduce, forage, and avoid predation
  • In many rivers it allows for the passage of migratory fishes into freshwater ecosystems providing marine-derived nutrients to rivers, boosting overall biodiversity and supporting healthier, more productive riparian zones
  • Improves the genetic diversity and resiliency of aquatic organisms by removing barriers that isolate populations
  • Lowers downstream water temperatures by eliminating the reservoir's thermal stratification and restores cold-water habitats crucial for native fish and other aquatic organisms
  • Boosts downstream oxygen levels by restoring natural flow and reduces nutrient buildup that fuels oxygen-depleting algae
  • Allows for the transport of sediment which is vital for building and nourishing ecosystems, creating fertile floodplains, and maintaining river channels
  • Allows rivers to regain natural seasonal flow patterns which are essential for triggering fish spawning, maintaining channel structure, and supporting diverse aquatic and riparian habitats. 

Improvements to Public Safety

Some dams can create a public health hazard without a risk to downstream inhabitants. Low-head dams (sometimes known as "drowning machines") are typically less than 15' high, have relatively low storage, and span the entire width of a river. Low-head dams are not always visible from upstream locations, creating an invisible hazard for swimmers or kayakers. The continuous flow of water and the geometry of the dam create an ongoing recirculating current that can trap people underwater. There have been an estimated 1,400 fatalities from low-head dams in the United States. Removal (or modification) of low-head dams can eliminate the risk that these structures pose.

For further information contact the DEEP Dam Safety Regulatory Program at (860) 424-3706 or by email at DEEP.DamSafety@ct.gov

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Content last edited February 2026