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Dam Safety: Hot Topics in Dam Safety

What are dam owners focused on with regard to safety? In the U.S., funding for dam safety work is a primary concern, and in Canada public safety around dams is an emerging topic.

By Elizabeth Ingram

Safe dams are a high priority for every hydroelectric project owner or operator. And there are significant issues that affect dam safety work in the U.S. and Canada, such as funding needed versus funding available for safety improvements, as well as the lack of public awareness about dams and safety. This article discusses these and other hot topics with regard to dam safety in both countries.

Dam safety in the U.S.

In the U.S., dam safety is primarily handled at the state level. Overall, how are these states doing? In its 2009 Report Card for America's Infrastructure, the American Society of Civil Engineers gave dams a D grade. ASCE says more than 4,000 of the 85,000-plus dams in the U.S. are deficient, including 1,819 high-hazard-potential dams (based on 2007 data). In addition, ASCE said that $12.5 billion in investment was needed over five years to address this issue. By contrast, actual spending is estimated at $5.05 billion.

With regard to hot topics in dam safety, the Association of State Dam Safety Officials - a non-profit organization serving state dam safety programs and the broader dam safety community - says several issues are perennially hot in the U.S. These are:

- Increasing numbers of high-hazard-potential dams. Failure or misoperation of a dam could result in release of the reservoir contents and loss of human life, disruption or destruction of local infrastructure and businesses, and property and environmental damages. In general, high hazard refers to a dam where failure is expected to cause loss of human life. There are more than 11,000 state-regulated high-hazard-potential dams in the U.S., and the number is increasing because of the development occurring downstream of dams. This trend of "hazard creep" is a concern, as dam safety regulators generally have no control over local zoning issues or developers' property rights.

- Funding for maintaining safe dams. More than half (58%) of all U.S. dams are privately owned and produce no revenue. Local and state governments own about 20% of dams nationwide, and the federal government and public utilities own only a small percentage. Accordingly, lack of funding for dam upgrades is a serious problem. Operation, maintenance and rehabilitation of dams can cost from the low thousands to millions, and responsibility for these expenses lies with owners. Although some states offer loan programs, funding assistance through government or private sources is minimal. In 2009, ASDSO concluded it would take about $16 billion to perform rehab work needed at the nation's most critical dams.

- Lack of authority and resources for state dam safety programs. Although most states have legislative authority to carry out a comprehensive dam safety program, many are lacking in specific areas. Some states lack authority for safety regulation of certain types of dams. Others have limited ability to enforce the law. Many states are simply under-resourced. On average, each state dam safety program staff member is responsible for the oversight of 208 existing dams, in addition to new construction.

- Lack of public awareness. Dams affect the public but are rarely the subject of public comment. Developers build in dam break inundation zones without considering the risks, and people living in these areas may be completely unaware a dam lies upstream. Many dam owners do not realize their responsibility for ensuring the safety of the downstream public and environment or understand proper dam maintenance and upgrade techniques. Messages that dams are bad for the environment may mislead the public into thinking all dams should be removed instead of maintained.

Obviously, significant work is needed to further dam safety work in the U.S. ASDSO has a mission to advance and improve the safety of dams through multiple avenues. To that end, ASDSO had a variety of work programs in progress, including: a program of study for dam safety professionals, training and information resources for dam owners, a library of dam safety guidelines and publications, a variety of technology transfer forums (a quarterly journal, website and conferences), and more.

Others in the U.S. also are working to advance dam safety. For example, legislation introduced in July will provide continued funding for dam safety. The Dam Safety Act of 2012 will extend funding authorization for the National Dam Safety Program, which provides grants to improve state dam safety programs through training, technical assistance, inspection and research. NDSP is administered by the Department of Homeland Security's Federal Emergency Management Agency.

The Dam Safety Act will reauthorize NDSP for fiscal years 2012 through 2016 at $13.9 million per year, including:

- $9.2 million per year split among the states, based on the relative number of dams per state, to make improvements in programs identified in the National Dam Safety Program Act;
- $1.45 million per year in research funds to identify effective techniques to assess, construct and monitor dams;
- $1 million per year for a nationwide public awareness and outreach program;
- 50,000 per year in training assistance to state engineers; and
- $500,000 per year for the National Inventory of Dams.

To highlight dam safety, on May 31, 2012, NDSP recognized National Dam Safety Awareness Day. This date was chosen in commemoration of the devastation that occurred on this day in 1889, when South Fork Dam in Johnstown, Pa., failed. This was the worst dam failure ever in the U.S. in terms of lives lost and injuries, with 2,200 people killed and thousands left homeless.

The event was held at Lake Needwood Dam in Rockville, Md., chosen because of the successful emergency action planning that took place in response to a severe leakage incident in July 2006. FEMA says the planning and response to that incident by state and local officials symbolizes what FEMA and its partners strive to achieve through NDSP.

During ceremonies, FEMA leaders introduced a new five-year strategic plan for NDSP. This plan presents a partnership-based approach for reducing the risk and consequences from dam failures for the next five years. The strategic plan presents a cross-section of activities designed to meet the goals of the program. Attaining these goals will increase community and regional resilience in the event of dam failures, improve life safety, reduce economic losses and minimize security disruptions. The five goals are:

- Reduce the likelihood of dam failures;
- Reduce the potential consequences in the event of dam failures;
- Promote public awareness of the benefits and risks related to dams;
- Promote research and training for state dam safety and other professionals; and
- Align relevant federal programs to improve dam safety.

The Federal Energy Regulatory Commission also is taking seriously the issue of dam safety. In May 2012, FERC ordered owners of high- and significant-hazard dams to submit Owners Dam Safety Program safety reports for their structures. Spurred by the 2005 failure of the upper dam of the 408-MW Taum Sauk Pumped-Storage project in Missouri, FERC developed a self-assessment tool so dam owners could review the effectiveness of their dam safety programs. Previously, FERC required ODSP filings case by case.

In a new initiative, FERC sent letters announcing that all owners of high- and significant-hazard dams under its jurisdiction must submit within 30 days a plan and schedule to file individual ODSPs. The letter said dam owners should plan to submit their actual ODSP documents within six months.

FERC says basic principles of a good dam safety program include:

- Acknowledgment of dam safety responsibilities;
- Communication;
- Clear designation of responsibility;
- Allocation of resources to dam safety; and
- Learning organization.

The letter included an outline of items to be included in each ODSP filing.

Dam safety in Canada

In Canada, regulation of dams is the responsibility of the province/territory. Canada does not have a federal regulatory agency or overarching program for dam safety. The Canadian Dam Association was formed in the 1980s to provide dam owners, operators, consultants, suppliers and government agencies with a national forum to discuss issues of dam safety in Canada. CDA's Dam Safety Guidelines, revised in 2007, have become a reference document for owners and regulators. The guidelines include a set of principles applicable to all dams and an outline of processes and criteria for management of dam safety. One important process is the periodic dam safety review, which has been adopted as a requirement by many regulators.

Only four of the 13 Canadian provinces and territories have in place legislation or guidelines governing dam safety, says Clare Raska, chair of CDA's Dam Safety Committee. For the most part, dam safety in Canada relies on an owner's due diligence. Where legislation exists, criteria and performance measures are defined and the owner must prove that the dam meets the regulated outcomes.

An important subject for discussion in Canada is the application of a risk-informed approach versus a traditional standards-based approach to dam safety assessment, Raska says. It is important to recognize that combinations of non-extreme conditions can be more important in safety assessments than extreme loading conditions considered in isolation, and this is why interdependence and interactions within an integrated dam/reservoir/production facility/spillway system must be considered.

The considerations go beyond the engineering analysis of floods, earthquakes and other natural and technical hazards and into the broader range of hazards and decisions around dams. Discussions at a societal and governmental level are necessary to answer the question of how safe new or existing dams should be, thus leading to development of an appropriate framework for decision-making.

Recent work with regard to dam safety in Canada has turned attention to members of the public who encounter hazards created by the presence and operation of a dam, Raska says. In 2011, CDA published Guidelines for Public Safety around Dams, and the association now offers a two-day workshop program on management of the public safety risks.

In one example of dam safety work in the country, the government of Saskatchewan has allocated about US$6.7 million in the province's 2012-13 budget to dam safety. That money - up $2.6 million from this past year - will allow the Saskatchewan Watershed Authority to rehabilitate several dams, including Moose Mountain, Gardiner, Alameda and the Lumsden Flood Control Project.

The 2012-2013 budget includes $2.1 million for Saskatchewan's Dam Safety Program, which will help fund emergency preparedness plans for three dams.

Another hydro utility in Canada performing dam safety work is BC Hydro, which is overhauling its 126-MW John Hart Generating Station. In July 2011, British Columbia released its first-annual dam safety report, one of a dozen recommendations made by the deputy solicitor general after the failure of Testalinden Dam in June 2010. There are about 1,900 dams in the province, of which 1,200 are considered low risk.

John Hart was one dam cited in this report for further examination. The upgrade project seeks to address safety, reliability and environmental issues surrounding the 65-year-old facility.

Elizabeth Ingram is senior editor of Hydro Review.


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