Early in the morning on March 14, 2019, the 92-year-old Spencer Dam located on the Niobrara River in Nebraska failed due to a combination of ice accumulation and high flows. The failure resulted in destructive flooding downstream, resulting in loss of life and property in an area where such events are extremely rare. Buildings and bridges were washed away, large ice chunks, mud, and debris from the torrent accumulated across the floodplain obstructing vital roadways for emergency relief. One U.S. Geological Survey gage downstream showed that the river rose 11 feet (3.4 m) before the gage itself was destroyed.
Flood waters crested at over 17 feet downstream of Spencer Dam in an area where NWS specifies flood stage at 7 feet. As communities pick up the pieces from this devastating flood, several important questions have been raised about the safety of Spencer Dam. For example, was the dam properly maintained and operating as designed before the failure? Unfortunately, it is still too early to answer these questions, while engineers from the Nebraska Public Power District and the U.S. Army Corps of Engineers are currently working on the investigation. For more information: Lincoln Journal Star, Omaha World-Herald, CNN
