Water Quality

Hydropower offers clean, renewable energy, but water level fluctuations can affect water quality, due to changes in the flow of rivers and streams. Common water quality variables include changes in temperature, dissolved oxygen and gases, nutrients, and turbidity, which impact river health.


Water quality near dams is important because dissolved oxygen and temperature changes impact the survivability of fish. By improving water quality, dams can also operate more efficiently because they are meeting environmental requirements.

To address these issues, state and federal regulations set a minimum water quality standard that hydropower operators must monitor and maintain. PNNL water quality research and tools help inform hydropower decisions and operations.

Tools for Assessing Water Quality

PNNL’s modeling platform, Advancing Modeling Tools for Assessment of Long-Term Energy/Water Risks for Hydropower, was created in support of the U.S. Department of Energy’s Water Power Technologies Office, and allows users to model the potential likelihood and severity of instream flow changes and water temperature events under a range of potential climate scenarios. Based on model outputs, decision makers can evaluate alternative operations and infrastructure investments to mitigate risk to water quality.

PNNL has also developed a real-time autonomous water monitoring system to advance water quality measurement technologies and maximize power generation revenue with improved operation control. The system enables comprehensive monitoring and data collection with a mobile sensor platform that can operate in dangerous waters, increasing human safety.

In 2019, PNNL deployed its water quality monitoring device to evaluate the water quality near the High Rock Dam hydropower facility.

The PNNL system measures and collects data on changes in water temperature, dissolved oxygen, and turbidity. These data help advance understanding of the environmental effects of hydropower, leading to improvements in both hydropower operations and water quality.

Research topics