Frequently Asked Questions about Dam Removal
Are there any downsides or risks in dam removal?
It is possible for dam removal to have negative effects, especially in the short term. If there is a buildup of contaminated sediment behind a dam, for example, its immediate release could have a significant impact on downstream habitats. However, with careful planning, most of these effects can be reduced or eliminated. The pre-application process is especially useful in identifying potential pitfalls.
Does dam removal cause flooding?
With proper planning, dam removal should not cause flooding downstream. In many cases, dam removal reduces the risk of flooding upstream of the dam. For dams removed with a General Permit, one of the requirements is that "removal will not cause increased frequency or depth of flooding downstream."
How much does it cost to remove a dam?
Depending on the size and condition of a dam, removal can range from tens of thousands of dollars to millions of dollars.
A research paper from 2023 led to the development of a Dam Removal Cost Prediction Tool, which may be helpful estimating the cost of a project.
Who pays for dam removal?
The dam owner is responsible for paying for dam-related projects, including removal. However, there is often funding available from private, municipal, state, and federal sources. Check out the Dam Removal Resources page for more information on potential sources of money and other assistance.
What kind of permitting is required for dam removal?
The type of permit required depends on several factors:
- The dam's hazard classification
- The presence of sediment
- The potential for fish passage
- The expected effects of removal on the streambed, on public/private property, on infrastructure, and on stormwater detention
- The current state of the dam (intact, breached, etc.).
In order to determine permitting requirements for dam removal, scheduling a pre-application meeting is highly encouraged for dam owners.
I own an "AA" (negligible hazard) dam. Do I still need a permit to remove it?
A Dam Safety permit is not required for the removal of an "AA" dam. However, before an "AA" dam is removed, dam owners must contact their municipal Inland Wetland agent and the DEEP Land and Water Resources Division to determine other potential permitting requirements.
How long does it take to remove a dam?
Depending on the situation, the physical removal of the dam can take anywhere from a few days to several years. Factors like dam size and sediment control are often critical factors.
The design and permitting of a dam's removal are also necessary aspects of the overall removal process. Owners should anticipate at least one year for the completion of those activities.
Additional critical activities (e.g. testing, engineering studies, fundraising, etc.) can often take longer than the design/permitting/removal. Some dam removal projects can take decades to complete.
For further information contact the DEEP Dam Safety Regulatory Program at (860) 424-3706 or by email at DEEP.DamSafety@ct.gov
Content last edited November 2025