Waste Heat Treatment Facility

Cooling Lagoons

North Anna Power Station uses water from Lake Anna to condense steam back to water inside the station. The water is returned to the lake slightly warmer than when it was taken. The discharged water cools in a series of private cooling lagoons, known as the Waste Heat Treatment Facility (WHTF). When North Anna is in full operation, approximately 2,000,000 gallons of water pass through the station per minute.

Reservoir and WHTF Background

Lake AnnaLake Anna was developed to provide cooling water for North Anna.

It was originally timberland and some farmland. When construction of North Anna began, the area that would become the lake bottom was completely cleared in 1968 before filling with water.

In 1972, the North Anna River was impounded, forming Lake Anna and the adjacent Waste Heat Treatment Facility.

Lake Anna is 17 miles long, 1 1/2 miles wide, and offers 200 miles of shoreline. There are 9,600 acres in Lake Anna and 3,400 acres in the private WHTF. In 1972, the Commonwealth of Virginia stocked the lake with 5 1/2 million fish, and it is restocked periodically. Some 33 species of fish thrive in the lake, including largemouth bass, striped bass and catfish.

Lake Anna Conditions

Lake Anna's water level and temperature readings are updated once each weekday. The temperature is measured in water being drawn directly from the main lake into the station's intake. The lake level is based on feet above sea level as measured at the main dam.

Date Temperature (deg. F) Lake Level (ft.)

Discharge Water Temperature

By design, the temperature of the discharge water is typically 14 degrees warmer than the intake water. Intake temperatures can fluctuate with seasons or weather conditions. View the current temperature of the discharge water below as it initially leaves the station. The data is updated approximately every 15 minutes. ("Refresh" your browser for the latest reading.)

Water Temperature - Station Discharge
Date Time Degrees F
Jul 1014598
Jul 1013098
Jul 1011598
Jul 1010098
Jul 104598
Jul 103098
Jul 101598
NYSE : (July 9, 2014) D 69.20 0.05