Laserfiche WebLink
CHAPTER 8. DAM FAILURE <br />8-2 <br /> <br />Figure 8-1. Historical Causes of Dam Failure <br />8.1.2 Regulatory Oversight <br />The potential for catastrophic flooding due to dam failures led to passage of the National Dam Safety Act <br />(Public Law 92-367). The National Dam Safety Program requires a periodic engineering analysis of every <br />major dam in the country. The goal of this FEMA-monitored effort is to identify and mitigate the risk of <br />dam failure so as to protect the lives and property of the public. <br />Washington Department of Ecology Dam Safety Program <br />The Dam Safety Office (DSO) of the Washington Department of Ecology regulates 1,073 dams of the 1,215 <br />total dams in the state that impound at least 10 acre-feet of water. The DSO has developed dam safety <br />guidelines to provide dam owners, operators, and design engineers with information on activities, <br />procedures, and requirements involved in the planning, design, construction, operation and maintenance of <br />dams in Washington. The authority to regulate dams in Washington and to provide for public safety is <br />contained in the following laws: <br />– State Water Code (1917)—RCW 90.03 <br />– Flood Control Act (1935)—RCW 86.16 <br />– Department of Ecology (1970)—RCW 43.21A <br />Where water projects involve dams and reservoirs with a storage volume of 10 acre-feet or more, the laws <br />provide for the Department of Ecology to conduct engineering review of the construction plans and <br />specifications, to inspect the dams, and to require remedial action, as necessary, to ensure proper operation, <br />maintenance, and safe performance. The DSO was established within Ecology’s Water Resources Program <br />to carry out these responsibilities. <br />The DSO provides reasonable assurance that impoundment facilities will not pose a threat to lives and <br />property, but dam owners bear primary responsibility for the safety of their structures, through pro per <br />design, construction, operation, and maintenance. The DSO regulates dams with the sole purpose of <br />reasonably securing public safety; environmental and natural resource issues are addressed by other state <br />agencies. The DSO neither advocates nor opposes the construction and operation of dams. <br />Foundation Defects <br />30% <br />Overtopping <br />34% <br />Other <br />6% <br />Conduits and Valves <br />10% <br />Piping and Seepage <br />20%