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Water: Cooling Water Intakes (316b)

Basic Information

EPA is developing regulations under §316(b) of the Clean Water Act. §316(b) requires that the location, design, construction and capacity of cooling water intake structures reflect the best technology available for minimizing adverse environmental impact. More than 1,500 industrial facilities use large volumes of cooling water from lakes, rivers, estuaries or oceans to cool their plants, including steam electric power plants, pulp and paper makers, chemical manufacturers, petroleum refiners, and manufacturers of primary metals like iron and steel and aluminum.

Cooling water intake structures cause adverse environmental impact by pulling large numbers of fish and shellfish or their eggs into a power plant's or factory's cooling system. There, the organisms may be killed or injured by heat, physical stress, or by chemicals used to clean the cooling system. Larger organisms may be killed or injured when they are trapped against screens at the front of an intake structure.

There are three rulemaking phases addressing cooling water intakes:

  • Phase I rule, promulgated in 2001, covers new facilities
  • Phase II rule, promulgated in 2004, covers large existing electric generating plants
  • Phase III rule, promulgated in 2006, covers certain existing facilities and new offshore and coastal oil and gas extraction facilities
Clean Water Act

Sec. 316. Thermal Discharges.
(b) Any standard established pursuant to section 301 or section 306 of this Act and applicable to a point source shall require that the location, design, construction, and capacity of cooling water intake structures reflect the best technology available for minimizing adverse environmental impact.

Related Clean Water Act Program: Sec. 402, National Pollutant Discharge Elimination System (NPDES)


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