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Cooling Water Intake Structure


Section 316(b) provides that any standard established pursuant to sections 301 or 306 of the Clean Water Act and applicable to a point source shall require that the location, design, construction, and capacity of the cooling water intake structures (CWIS) reflects the best technology available for minimizing adverse environmental impact. This regulation is unique in that it applies to the intake of water and not the discharge. A major goal of this regulation is to minimize the impingement and entrainment of fish and other aquatic organisms as they are drawn into a facility's cooling water intake.

  • Impingement occurs when fish and other aquatic life are trapped against cooling water intake screens.
  • Entrainment occurs when aquatic organisms, eggs and larvae are drawn into a cooling system, through the heat exchanger, and then pumped back out.


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Last updated on December 29, 2010 1:25 PM