The cost of rehabilitating federal and non-federal dams in the United States has risen to more than $70 billion according to a 2019 update of a report from the Association of State Dam Safety Officials (ASDSO). The cost to rehabilitate those dams where the risk is highest exceeds $23 billion.

Using the information in the 2018 National Inventory of Dams (NID), a database published by the U.S. Army Corps of Engineers, ASDSO can estimate the cost of rehabilitating our nation’s more than 90,000 dams. In 2003, ASDSO published its original cost estimates in a report entitled The Cost of Rehabilitating Our Nation’s Dams: A Methodology, Estimate and Proposed Funding Mechanisms. The report was updated in 2009, 2012, 2016 and 2019.

Current figures place the total cost estimated for non-federal dams at $65.89 billion, up from the last estimate of $60.70 billion. Non-federal, high-hazard potential dams are estimated at $20.42 billion, up from $18.71 billion. High-hazard potential dams are those where failure or mis-operation will likely lead to loss of human life.

Since the 2012 update, the cost of federally owned dams has also been considered. In the current update, it is estimated that $4.78 billion is needed to rehabilitate all federally owned dams, with $3.35 billion of this attributed to federally owned high-hazard potential dams.


Non-Federal High Hazard - 14,343 dams - $20.42 Billion

Non-Federal - 87,640 dams - $65.89 Billion

Federal - 3,828 dams - $4.78 Billion

Federal High Hazard 1,286 dams - $3.35 Billion

An important step towards reducing this cost is creating and supporting funding assistance by the federal government and individual states. Currently, lack of funding for dam upgrades is a serious national problem, especially within the private sector. Unlike most infrastructure facilities, the majority of dams in the United States are privately owned, leaving owners solely responsible for financing dam upkeep and upgrades.

On the state level, ASDSO encourages loan and grant programs for rehabilitation funding. A dam safety program cannot be complete without a mechanism to address funding for dam repairs and rehabilitation, and while a few states have already established these programs, the majority have not. On the national level, ASDSO encourages full funding for the High Hazard Potential Dam Rehab Grant Program and for federal agencies to continue supporting dam safety initiatives.

Occasional upgrade or rehabilitation is necessary due to deterioration, changing technical standards, improved techniques, better understanding of the area's precipitation conditions, and changes in downstream populations or land use. Without proper maintenance, repair and rehabilitation, our nation’s dams may become unable to serve their intended purpose and could be at risk for failure. Dams must be maintained to keep them safe. As this vital maintenance, repair, and rehabilitation is delayed, the cost of rehabilitation will only continue to rise.

Read the full report - The Cost of Rehabilitating Our Nation's Dams (2019)


Note: The ASDSO estimates are based on general assumptions about the types and numbers of repairs needed. Actual rehab costs available from dam owners supersede our estimates; this is especially true for the federal dams where the federal agencies have more precise estimates based on actual repair needs. Further, we acknowledge that our estimate for the federal subset of dams may be low.