SACE | Southern Alliance for Clean Energy

Power Plants and Water


Vogtle cooling towers 3Traditional power plants must have significant water resources continuously and readily available to create and condense steam to power their turbines. Water use or withdrawal refers to the amount of water that is withdrawn from the water body by the power plant. Water consumption refers to the amount of water that the power plant withdraws that is not returned to the water supply source, water that is “lost” or “consumed,” primarily due to evaporation.

Water withdrawals and consumption figures depend heavily on what types of cooling technologies are used. Power plants that use once-through systems (i.e., do not have cooling towers) withdraw and heat very large volumes of water but little is consumed because direct evaporation is low. In contrast, “closed cycle system” power plants that use cooling towers do not need to withdraw nearly as much water, but their cooling tower evaporation means a much higher rate of water consumption. Cooling towers offer environmental and engineering advantages over once-through systems, but they consume a lot of water. In the Southeast, some power plants use cooling towers some or all of the time, while others do not. SACE helped release two reports by the Union of Concerned Scientists as part of the Energy and Water in a Warming World initiative (EW3), Freshwater Use By U.S. Power Plants and Water-Smart Power: Strengthening the U.S. Electricity System in a Warming World. The reports highlight the vast connections between energy and water in our country and in particular in our region here in the Southeast. Learn more about the EW3 initiative and find the reports here.


Nuclear and coal-fired power plants degrade our region’s precious water resources by affecting both water quality and water quantity. These types of power plants also release a wide variety of contaminants directly and indirectly into communities’ water supplies.

A notable impact from existing nuclear and fossil fuel power plants in the region is that they require massive quantities of water to operate, competing with other important uses such as drinking water needs, recreation, fishing, and industrial uses. They must be located next to large bodies of water or have significant water resources readily available to create steam to power the turbines. Nuclear power plants have a special need for large, continuous water supplies to cool the nuclear fuel rods in their reactor core to prevent a catastrophic meltdown accident.

A host of energy projects have been selected year after year by the Georgia Water Coalition, of which SACE is an active member, for their infamous, “Dirty Dozen” report of worst offenders to Georgia’s waterways. The 2016 Dirty Dozen report has 8 of the 12 culprits from the energy sector. Find all the Dirty Dozen reports here.

To see how much water on average is consumed, or lost primarily through evaporative loss, by electricity production in your state per kilowatt hour of electricity, see Table 3 of PDF from a National Renewable Energy Laboratory report.

Thermal pollution, or heat generated from operating the power plant, is another form of water pollution caused by nuclear and coal plants that changes the temperature of the nearby waterway. This can then harm the surrounding ecosystem, including the breeding habits of a fish species or the amount of oxygen available to plants or microorganisms. Thermal pollution is a particular issue of concern during drought conditions since the water resource is already stressed.

Coal-fired power plants:

  • require massive amounts of water to produce electricity;
  • release mercury emissions that contaminate lakes and rivers, making recreation and eating fish unhealthy. Airborne mercury emissions eventually find their way into water sources, generally through rainfall;
  • rank as the largest industrial source of mercury emissions in the region;
  • release other hazardous chemicals during routine operations.
  • produce toxic coal ash in large quantities commonly stored in unlined impoundments close to waterways. Coal ash is not federally regulated, though it is known to pollute ground and surface waters with dangerous contaminants.
    • SACE published many coal ash-focused blogs, including educational series such as the Southeast River Runs, which highlighted the impacts of coal ash on rivers throughout the region and maintains the dynamic website to help communities identify and learn more about the threats from coal ash.
    • Along with our partners, the Georgia Water Coalition, selected the threats to the Coosa River from Georgia Power’s Plant Hammond for the 2016 Dirty Dozen list.

Way back in December 2010 SACE and our allies submitted comments on the re-issued surface water withdrawal and water discharge permits for Plant Washington, a new coal-fired power plant proposed in Georgia. Unfortunately state regulators approved the permit, though the proposed coal plant is still dogged by other financial and environmental problems. Read more about Plant Washington here.

Nuclear power plants:

  • are the most water-intensive electricity supply choice, on average withdrawing and consuming more water than other energy options, including coal fired power plants;
  • release contaminants, including hazardous chemicals such as biocides, solvents, and anti-scaling compounds along with heavy metals like chromium, directly into waterways;
  • release radioactive airborne emissions, such as tritium, a radioactive form of hydrogen, that ends up polluting surrounding water and land through rainfall;
  • have the ability to severely harm large bodies of water in the event of an accident.

For three years running (in November 2012 & 2013 and October 2014) the Georgia Water Coalition selected the proposed new Vogtle reactors in Georgia as one of the “Dirty Dozen” due to it’s large water withdrawals and consumption from the Savannah River along with toxic discharges. SACE and our partners are very concerned about the impacts Vogtle has on the Savannah River, both in terms of water quantity and quality. The situation will only get worse if the two new Vogtle reactors begin operating, currently estimated for some time in 2019 and 2020 respectively. We filed comments with the Georgia Environmental Protection Division (EPD) in March 2014 opposing the massive draft surface water withdrawal permit for the new reactors and requesting a public hearing. We were successful and a public hearing was held in May. Find all our comments and more in our blog post here. Unfortunately, EPD disregarded the public’s concerns despite receiving over 250 comments, the majority of which urged for EPD to deny or at least delay issuance of the permit. The agency issued the final permit on December 5, 2014 and the State of South Carolina initially challenged the permit, but eventually withdrew and the permit was finalized.

In mid-January 2015, EPD issued a draft surface water discharge permit (National Pollutant Discharge Elimination System or “NPDES”) for review and held a public hearing in Augusta on March 3 with public comments due March 20. SACE and our allies are very concerned about the impacts this could have on the already imperiled Savannah River, the 3rd most toxic river in the U.S. Find SACE’s comments from the March 3rd hearing here and our full comments filed with EPD on March 20 here. Despite all the objections, EPD issued the final permit in late September 2015.

Unfortunately bad choices for our water future continue to be made in Georgia. Georgia Power is exploring building two more reactors along the Chattahoochee River, in 2016 designated as America’s Most Endangered River and the PSC approved $99 million could be spent to explore what we already know is an unsuitable site. Our work and support from partners led to the Georgia Water Coalition selecting this water-hogging boondoggle for the 2016 Dirty Dozen list.