Dam safety: How technology can help dam owners and operators overcome 3 challenges
September 14, 2023
Risk-informed decision-making for dams in the face of climate change, aging infrastructure, and resource limits
When Texas suffered through a deadly ice storm in February 2021 all it needed was more electricity. For nearly 10 days, people saw the temperatures in their homes go down, down, down.
Why?
The power grid failed. At the peak of the power outage, nearly 10 million people in Texas were without power. As the climate changes, we should expect to see those sorts of things more often. Floods, wildfires, ice storms, hurricanes. They all threaten the power grid.
Yet one of the solutions to boost the grid is one of our oldest pieces of infrastructure: dams.
Ice and snow created deadly conditions throughout Texas in early 2021.
Dams have been around since at least the fourth century B.C.E. Some are large. (Think the Hoover Dam.) Many are much smaller. They fill multiple roles¡ªfrom power generation to flood control and a source of drinking water.
And those dams are facing multiple challenges. Among the greatest are climate change, age, and resource limitations. Good news: new technology can limit the potential impacts to maintaining safe dams.
Dam safety in a changing climate
Climate change. It¡¯s part of the daily news cycle. And one of the biggest challenges for dam owners and operators.
Like the Texas ice storms, extreme weather events are more frequent. In the US, we¡¯re seeing ¡°100-year¡± rain events occurring at intervals well under a century. For instance, a parade of Pacific storms from the end of 2022 through March 2023 led to flooding and a federal emergency declaration for 17 counties in California.
Currently in Texas, we¡¯re helping design a flood management project that includes a new 26.7-mile floodwall system and ecosystem restoration. The project covers a stretch of coastline that has been devastated by storms¡ªincluding hurricanes Harvey and Nicholas¡ªover the past decade.
A map of the flood management project that will improve the floodwall system along the Gulf coast of Texas, from Sabine Pass to Galveston Bay.
If this were just 20 years ago, we would design the project for a standard level of protection. Now, the level of protection considers how the climate is changing, storm frequency, and population growth. The design factors in the likelihood of future hazards and the potential consequences.
Dam safety as dams get older
Many dam structures across North America have operated for more than 50 years. Aging assets can impact safe operating conditions.
Deterioration can occur in the dam structure itself but also in the spillways and outlet works. We simply can¡¯t evaluate and treat these issues the same way as we did in the past.
We must apply new approaches. Design standards must evolve to combat the effects of aging infrastructure and resource constraints.
Our teams install automated instrumentation at dam sites to collect data. This saves time and money as many dam facilities are difficult to access and can¡¯t be watched 24/7.
Risk-informed decision-making has become the industry standard. We use instrumentation to gather real-time data, which helps us best understand project risks. This allows us to tailor our efforts according to which dam assets need the most attention.
We¡¯ve worked with Newport News Waterworks in Virginia for almost eight years. One of our first projects was to investigate seepage at one of their dams. Seepage issues had existed at this facility since it was first built in the early 1980s.?
A photo of a sand boil catalyzed by internal erosion at the Newport News Waterworks site in Virginia.
Through modeling and data review we determined that conditions were favorable for internal erosion. New instruments at the dam helped provide the all-important data.
Newport News Waterworks reached out to us a year later reporting sand boils at the downstream toe of the dam. We performed enhanced inspections and monitoring. Ultimately, we recommended they draw the pool down to temporarily stop the internal erosion.
We¡¯re now working to design a permanent solution to improve the dam and mitigate the erosion issue. That will allow the client to bring the pool back up to the full reservoir level, restoring public lake access and resiliency to the water supply.
Dam safety with limited resources
Over the past decade, dam owners and operators have faced more regulation and inspection from the Federal Energy Regulatory Commission (FERC). This is in addition to their regular maintenance efforts. The result? Increased costs and ballooned budgets.
And as dam infrastructure ages, repairing assets costs more time and money. Operators are stretched thin. Using technology is a major factor in addressing resource constraints, while still focusing on dam safety.
Our teams install automated instrumentation at dam sites to collect data. This saves time and money as many dam facilities are difficult to access and can¡¯t be watched 24/7. At the same time, digital twins are helping model facilities and their real-time performance.
We install instrumentation like piezometers at many dam sites to help risk-informed decision making. For example, we¡¯ve installed open standpipe piezometers in seven locations around the penstock stilling basin at Bluestone Dam in West Virginia.
We¡¯re supporting a pilot project with the Tennessee Valley Authority to use risk analysis to inform dam design.
We¡¯ve installed instrumentation on their dam assets. It helps us better understand and reduce uncertainty associated with certain failure modes. Now that we understand the risks associated with their current assets, we¡¯re tailoring the design solution to mitigate the most critical risks.
Technology can help dam owners make risk-informed decisions. And that leads to financially wise investments to improve public safety.
Digital solutions for dam safety
Our team has developed a digital solution called Stantec Mosaic?. It gives owners all the instrumentation data at their fingertips to streamline the operations of their facilities.
We can configure the information dashboard to link instruments and inspection observations directly with potential failure modes. This allows owners to stay focused on managing their most critical risks.
In 2020, we started working with one of the largest renewable power producers in North America as its engineer of record. We are aggregating all their dam-asset data and migrating it into Dam Insights.
We¡¯re doing that by connecting sensor and GIS data into our Internet of Things hub. This allows the client to make risk-informed decisions faster.
Technology can help reduce the stresses on dam owners from climate change, deteriorating infrastructure, or resource limitations.?