Electricity generation requires large amounts of water to produce steam, remove heat or power hydroelectric turbines. (Hydropower makes up about 6 percent of Southern Company system generation capacity.) Some of the water naturally evaporates—what you see rising out of the large cooling towers at steam power plants is water vapor. Some of the water at power plants is cooled and reused. Most is returned back to its source.
Environmental concerns regarding water principally relate to the quantity of water withdrawn and consumed from rivers and lakes, the quality of the water returned to the source, and any effects on aquatic life. Southern Company system plants withdraw, on average, almost 4.5 billion gallons of water per day; about 94 percent of that water is returned to the river or lake. Performance »
Southern Company is researching technologies—including fish return systems and fine mesh screens—to reduce the impact of power plant intakes on aquatic life.
Proposed new EPA standards for cooling water intake structures are expected in 2014. and establish national requirements for implementing the best technology available for protecting fish from the potentially harmful effects of intact structures.
Southern Company supports reasonable regulations that take into account the great variation of impacts from plant to plant, but national standards without flexibility for site-specific issues are unwarranted.
The National Pollutant Discharge Elimination System controls water quality by regulating point source discharges into U.S. waterways. Southern Company system power plants have water discharge permits for pH, suspended solids, oil and grease, chlorine, temperature, iron, and other parameters. Typical permitted discharges include cooling water, ash ponds, coal pile runoff ponds, metal cleaning waste ponds, sump overflows, and oil/water separators. These points are monitored or sampled periodically in accordance with permit requirements.
Certain EPA regulations, called effluent guidelines, address materials discharged by thermoelectric power plants. EPA proposed revisions to the effluent guidelines in April 2013 regulating discharges primarily associated with coal combustion byproducts, such as coal ash and scrubber wastewaters. Southern Company has been actively engaged with EPA and the electric power industry to compile information for the rulemaking process by providing critical data and evaluating the feasibility and costs of available treatment technologies. Southern Company seeks to ensure compliance in the most cost-effective and efficient manner, while providing continued protection of water quality and aquatic resources.