Fix the Dam Concrete: Aging U.S. Dams Face Urgent Repairs

With America’s dams showing their age, utilities have an opportunity to tap into federal funding and modernize critical concrete infrastructure before costly failures strike.

In the U.S., hydropower generates nearly 27% of renewable electricity and 93% of all utility-scale storage, yet the average dam is nearly 80 years old, according to the U.S. Department of Energy. The American Society of Civil Engineers recently gave U.S. dams a sobering grade of D, underscoring the urgent need for upgrades.

Now, $3.5 billion in federal funding is available to support these improvements. To qualify, projects must meet one of three criteria, including replacing deteriorated concrete to prevent erosion and water seepage. This creates a prime opportunity for operators to invest in materials that not only meet the requirements but also maximize the value of every federal dollar.

The issue resonates globally as well with nearly 59,000 big dams — constructed between 1930 and 1970 — throughout the world, each designed to last only 50 to 100 years, according to research from the U.N. University’s Institute for Water, Environment and Health. According to the International Energy Association, by 2030, more than 20 percent of the global generating units will be older than 55 years and in need of replacement.

Concrete forms the skeleton of a hydroelectric plant, not only serving as its foundation but extending into every vital structure, from turbine housings and dam walls to intake tunnels and spillways. These critical structures are vulnerable to breaks and fractures. Under constant hydraulic pressure, the concrete begins to develop microcracks — tiny fissures that may be invisible at first but grow over time. Water seeps into these cracks, carrying harmful chemicals that react with the cement paste, weakening the internal matrix. Dissolved sulfate in particular can penetrate and disrupt the hardened concrete, while leaching slowly strips away the binding materials that hold it together.

Along with these chemical attacks, the physical forces at play are just as strong. In a hydroelectric dam, high-velocity flow carries sediment that wears down concrete surfaces, grinding away protective layers and exposing the reinforcement steel. As corrosion occurs, the steel expands and puts pressure on the concrete, causing further cracking and spalling.

With all these threats to hydroelectric infrastructure, operators face mounting risks. Lost revenues from downtime and regulatory fines can quickly add up, especially when costly emergency repairs are needed, as unplanned shutdowns can cost hundreds of thousands of dollars per day. Dam managers also face recurring maintenance like patching, coating reapplications, which add to the strain. Over time, these interruptions not only drain budgets but also compromise operational reliability, leaving facilities more vulnerable to unexpected failures during peak demand or extreme weather events.

Fortunately, there are proven ways to reduce these costs and strengthen dam infrastructure. One of the most effective is the use of permeability-reducing admixtures (PRAs) and abrasion-resistant admixtures, which have been in use for decades and have a long track record of extending service life in some of the world’s most challenging environments.

Kryton International has been at the forefront of waterproofing technology since inventing the first crystalline PRA of its kind in the 1980s. Its Krystol Internal Membrane (KIM) acts like an immune system for concrete, waterproofing it from the inside out. When mixed into the concrete, these admixtures chemically react with water and cement particles to form microscopic crystals within the concrete’s pores. These crystals block water entry, preventing leaching and microcracks. If a future hairline fracture does occur and water finds its way inside, the admixture reactivates, producing more crystals to seal the opening and restore the concrete’s defenses. Additionally, Kryton’s Hard-Cem acts as an abrasion-resistant admixture that increases surface hardness to resist water and sediment erosion.

Together, these technologies provide a comprehensive defense for concrete in hydroelectric dams. The waterproofing admixture eliminates pathways for seepage, protecting embedded steel from corrosion and preventing internal deterioration, while the abrasion-resistant mixture protects against high-velocity flows. This combination supports more consistent operations by reducing the risk of unscheduled repairs or unexpected outages, while also cutting long-term maintenance costs. These benefits translate into extended lifetimes for the structure and greater reliability for critical infrastructure.

Beyond durability and cost savings, there is a growing environmental imperative for improving the concrete used in hydroelectric infrastructure. With concrete being the world’s most used construction material, the production of cement is responsible for roughly 8% of global carbon dioxide emissions. Every time a concrete structure needs to be repaired or replaced, more cement must be produced, compounding the industry’s carbon footprint.

Permeability-reducing and abrasion-resistant admixtures help address this challenge by extending the lifespan of concrete structures, requiring less concrete production for maintenance in the long-run. By blocking the ingress of water and harmful chemicals, they reduce deterioration and eliminate the need for frequent replacement. This conserves maintenance time, energy, and resources, while also lowering the carbon footprint of the entire project.

The concrete replacement requirements in the federal funding program call for solutions that will perform under intense hydraulic pressure, resist chemical and physical wear and reduce the need for future maintenance. By extending service life and reducing environmental impact, these admixtures meet the industry’s demands for resilience, efficiency, and sustainability. Simply put, durable concrete is sustainable concrete.

The stakes for dam upgrades are high, but so are the rewards. With federal funding on the table, choosing concrete solutions that combine long-term durability with minimal maintenance and lower environmental impact ensures operators not only secure funding but also make the most of it. In the end, these choices will ensure the backbone of hydropower remains strong, efficient, and dependable for decades to come.