CS26A - Concurrent Session 26A: The Devil’s in the Details: Highlights from ASDSO’s DamFailures.org

In September 2015, the Association of State Dam Safety Officials (ASDSO), in cooperation with the Federal Emergency Management Agency (FEMA), released the Lessons Learned from Dam Incidents and Failures website (DamFailures.org). Since its release, over 500,000 users worldwide have accessed the site to learn about the many facets of dam safety.

Thanks to continued FEMA funding, website content continues to be expanded and diversified. This session will begin with a brief update on new content on the website. This will be followed by presentations about case studies from the website where seemingly small details were significant contributing factors. In all these cases, minor adjustments to design, operation, maintenance, or emergency planning could have made a significant difference in the outcome.

Presentations are as follows:

-DamFailures.org Update and Topic Introduction

-Case Study: Taum Sauk Dam - Taum Sauk Dam is part of a pump storage project in Missouri. On December 14, 2005, multiple levels of instrumentation failed which resulted in the reservoir being overfilled. The rock-fill dam failed by overtopping during the final minutes of one of its pumping cycles.

-Case Study: Tous Dam- Tous Dam in Valencia, Spain failed in 1982 during an intense hydrologic event. While the failure of the dam could largely be attributed to inadequate spillway capacity, several factors contributed to and accelerated failure of the dam including loss of power supply and site access.

-Case Study: Cleveland Dam - On October 1, 2020, software and human error during a dam maintenance project at Cleveland Dam in British Columbia caused its spillway gate to open unexpectedly. Several anglers downstream were swept into the river, and there were two fatalities. Following the incident, the dam owner initiated an extensive program to improve public safety and enhance the public warning system for the dam.

-Case Study: Tempe Town Lake Dam - On the evening on July 20, 2010, one of the rubber bladders that made up Tempe Town Lake Dam burst, releasing approximately one billion gallons of water. The failure was attributed to the intense heat of the dry Arizona desert and other environmental factors.