Fast Facts

The Federal Energy Regulatory Commission oversees over 2,500 dams used for hydropower. The near failure of a FERC-licensed dam in California in 2017 highlights the safety risks of dams. What does FERC do to ensure safety?

FERC engineers inspect dams and review engineering studies as key safety steps. This helps FERC understand the risks at individual dams. However, a lack of standard language and procedures for recording inspection results limits FERC's ability to identify comparable safety risks at other dams.

We recommended that FERC develop standard language and procedures for inspection information and assess safety risks portfolio-wide.

Dam and Related Key Structures

Illustration of a dam used to produce hydropower.

Illustration of a dam used to produce hydropower.

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What GAO Found

The Federal Energy Regulatory Commission's (FERC) staff generally followed established guidance in collecting safety information from dam inspections for the dams GAO reviewed, but FERC has not used this information to analyze dam safety portfolio-wide. For these 42 dams, GAO found that FERC staff generally followed guidance in collecting safety information during inspections of individual dams and key structures associated with those dams. (See figure.) However, FERC lacks standard procedures that specify how and where staff should record safety deficiencies identified. As a result, FERC staff use multiple systems to record inspection findings, thereby creating information that cannot be easily analyzed. Further, while FERC officials said inspections help oversee individual dam's safety, FERC has not analyzed this information to identify any safety risks across its portfolio. GAO's prior work has highlighted the importance of evaluating risks across a portfolio. FERC officials stated that they have not conducted portfolio-wide analyses because officials prioritize the individual dam inspections and response to urgent dam safety incidents. However, following the Oroville incident, a FERC-led initiative to examine dam structures comparable to those at Oroville identified 27 dam spillways with varying degrees of safety concerns, on which FERC officials stated they are working with dam licensees to address. A similar and proactive portfolio-wide approach, based on analysis of common inspection deficiencies across the portfolio of dams under FERC's authority, could help FERC identify safety risks prior to a safety incident.

Dams and Related Key Structures

Dams and Related Key Structures

FERC staff follow agency guidance and apply professional judgment to assess engineering studies on key aspects of dam performance and safety. Licensees and their consultants develop engineering studies that assess dam performance and safety in consideration of expected conditions—as related to hydrology and seismicity, for example—and that FERC staff then use to inform their safety determinations. FERC has established policies, such as requiring multi-layered reviews, to ensure the accuracy of these studies. For example, FERC's Engineering Guidelines provide a framework for the review of engineering studies, though the Guidelines recognize that each dam is unique and allow for flexibility and exemptions in its use. FERC staff use the studies to inform other components of their safety approach, including the analysis of dam failure scenarios and their review of safety to determine whether to renew a license.

Why GAO Did This Study

In February 2017, components of California's Oroville Dam failed, leading to the evacuation of nearly 200,000 nearby residents. FERC is the federal regulator of the Oroville Dam and over 2,500 other dams associated with nonfederal hydropower projects nationwide. FERC issues and renews licenses—which can last up to 50 years—to dam operators and promotes safe dam operation by conducting safety inspections and reviewing technical engineering studies, among other actions.

GAO was asked to review FERC's approach to overseeing dam safety. This report examines: (1) how FERC collects information from its dam safety inspections and the extent of its analysis, and (2) how FERC evaluates engineering studies of dam performance to analyze safety, among other objectives. GAO analyzed documentation on a non-generalizable sample of 42 dams associated with projects relicensed from fiscal years 2014 through 2017, selected based on geography and hazard classifications, among other factors. GAO also reviewed FERC regulations and documents; and interviewed FERC staff associated with the selected projects and technical consultants, selected based on the frequency and timing of their reviews.

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GAO recommends that FERC: (1) develop standard procedures for recording information collected as part of its inspections, and (2) use inspection information to assess safety risks across FERC's portfolio of dams. FERC agreed with GAO's recommendations.

Recommendations for Executive Action

Agency Affected Recommendation Status
Federal Energy Regulatory Commission FERC should provide standard language and procedures to its staff on how to record information collected during inspections, including how and where to record information about safety deficiencies, in order to facilitate analysis of safety deficiencies across FERC's portfolio of regulated dams. (Recommendation 1)
In March 2021, FERC told GAO that it plans to develop this year a Data and Management System (DAMS) that will facilitate the complete recording and subsequent analysis of safety deficiencies from inspections across FERC's portfolio of regulated dams. In preparation for the development of DAMS, FERC has formed a team to gather requirements for the system and standardize related work processes. GAO will continue to monitor FERC's efforts to implement this system.
Federal Energy Regulatory Commission FERC should use information from its inspections to assess safety risks across its portfolio of regulated dams to identify and prioritize safety risks at a national level. (Recommendation 2)
In March 2021, FERC told GAO that it had initiated 24 pilot projects to address the safety risks identified in the screening-level risk assessment that it had previously conducted to assess safety risks across the inventory of regulated dams and to help guide safety decisions. In addition, GAO confirmed that FERC has taken steps to enhance its ability to identify and prioritize safety risks at a national level by initiating a rule making process to update its dam safety regulations and associated engineering guidelines. Among other aspects, the updates would require a more comprehensive two-tier inspection procedure and enhance focus on the qualifications of the consultant teams who conduct dam inspections. GAO will continue to monitor FERC's efforts to implement this recommendation.

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