The federal agency charged with licensing nonfederal hydropower facilities in the U.S. has done a good job of evaluating the safety of individual dams but should do more to "assess and identify the risks across its portfolio," according to a new report by the U.S. Government Accountability Office.
The report, which was undertaken at the request of top Congressional Democrats in the wake of the February 2017 failure of the Oroville Dam in California, found that Federal Energy Regulatory Commission staff generally conducted and collected information from the 42 dam safety inspections reviewed consistent with established guidelines.
But because FERC lacks procedures specifying where and how that information must be recorded and agency staff stores it on multiple systems, the data cannot be easily analyzed to identify any safety deficiencies across the commission's entire portfolio of regulated dams, the GAO said.
FERC is responsible for maintaining safety at over 2,500 dams across the country, one of which is the Oroville dam at the Edward C Hyatt generating facility owned by the California Department of Water Resources. Heavy rains in February 2017 caused the reservoir at Oroville to reach its limits and the subsequent failure of both the main and auxiliary spillways, which led to the evacuation of nearly 200,000 residents from the area.
In its report titled "Dam Safety; FERC Should Analyze Portfolio-Wide Risks," the GAO recalled that the agency, in the aftermath of the Oroville event, undertook an initiative aimed at assessing safety risks at 184 projects that had spillway systems similar to the one at the Oroville dam. That initiative identified 27 spillways "with varying degrees of safety concerns" that FERC staff and the dam licensees are working to address, the GAO recounted.
"A similar and proactive approach based on analysis of common deficiencies across the portfolio of dams under FERC's authority could also help to identify any safety risks that may not have been targeted during the inspections of individual dams and prior to a safety incident," the GAO said.
FERC officials maintain that they have not conducted such an analysis because they "prioritize the individual dam inspections and response to urgent dam safety incidents," according to the report. While the GAO applauded FERC for designing "a multi-layered safety approach — which uses inspections, studies, and other assessments of individual dams — to reduce exposure to safety risks," the watchdog said that approach could be complemented by looking at the risks more holistically across the commission's portfolio of licensed dams.
The GAO therefore recommended that FERC develop standardized language and procedures for recording information collected during inspections and then use that information to assess and prioritize safety risks "at a national level." According to the GAO, FERC has seen a draft of the report and "generally agreed with [its] findings and found the recommendations to be constructive."
