Emergency Action Planning



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About EAPs

Dam Failure is A Familiar Missouri Threat


In Missouri, the first state legislation aimed at regulating dams was passed in 1889, and was called the Dam, Mills, and Electric Power Law. The law was concerned only with damages caused by construction and lake formation. It did not address the engineering aspects of design or downstream safety of dams.

Ninety years later, House Bill 603 was introduced in the Missouri legislature. This legislation passed and became effective in September 1979, largely due to an early indication from the Corps of Engineers inspection program that Missouri led the country in total number of unsafe dams.

House Bill 603 excluded certain dams from regulation – those less than 35 feet high, and allowed exemptions for others – those used primarily for agricultural purposes and those regulated by other state or federal agencies.

The problem with unsafe dams in Missouri was underscored by dam failures at Lawrenceton in 1968, Washington County in 1975, Fredricktown in 1977, and a near failure in Franklin County in 1978.

Missourians were again reminded of the consequences of dam failure in on December 14, 2005, when a 700-foot section of the Taum Sauk mountaintop reservoir collapsed. This sent a deluge of 1.5 billion gallons of water that scoured Johnson's Shut-Ins State Park, a popular site for camping, hiking, and picnics just a couple of hours from St. Louis. The park superintendent and his family were injured in the flood, but fortunately the park was otherwise empty and no lives were lost. The outcome may have been quite different during peak summer usage of the park. A technical damage evaluation can be found at: http://mcgsc.usgs.gov/publications/t_sauk_failure.pdf.

"This was one of the worst man-made disasters in Missouri's history," said Jay Nixon, then the state's attorney general and now its governor. Federal and state fines and lawsuit settlements totaling nearly $300 million followed in the years since as the Taum Sauk owner, the utility company AmerenUE, was held responsible for the damages. Repair of the dam is in process and is expected to cost AmerenUE $250 million.

Legislation subsequently was drafted and introduced in the Missouri General Assembly to strengthen the state's dam safety laws, including extension of Department of Natural Resources jurisdiction over many more dams. The Legislature is expected to consider the legislation again when it convenes in January 2010. A summary of that legislation is available online. A DNR summary of dam safety history, dam safety regulations in surrounding states, and recommended changes for Missouri can be read at http://www.ky3.com/home/related/2303711.html.

USDA's Natural Resources Conservation Service has provided a summary of dams at risk in Missouri that were built under provisions of Public Law 566.

In 1954, Missouri built its first small watershed dam. Today, over 600 dams have been built under the PL-566 small watershed program. The dams serve many functions, including flood control, erosion control, recreation, fish and wildlife habitat, water supply, and water quality improvement.

Most watershed projects include dams to impound water. These structures vary in size and perform multiple functions. Many of the dams have a designed life of 50 years. Missouri has 22 dams that are more than 40 years old, and most will need major rehabilitation soon. The original investment in existing dams needs to be protected. Rehabilitation is cheaper than reconstruction or new construction, but there is no local, state, or federal funding available. To begin rehabilitation, Missouri needs about $2 million and about $2 million per year for the next 10 years to keep pace with the needs.