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Water: New Facilities

Phase I—New Facilities

Final Rule, Phase I, Fact Sheet

EPA-821-F-01-017, November 2001


On November 9, 2001 EPA established location, design, construction and capacity standards for cooling water intake structures at new facilities. This final regulation will protect fish, shellfish and other forms of aquatic life from being killed or injured by cooling water intake structures. The rule sets standards but provides flexibility to demonstrate comparable performance.


Section 316(b) of the Clean Water Act requires EPA to ensure that the location, design, construction and capacity of cooling water intake structures reflect the best technology available for minimizing adverse environmental impact. For many years this provision has been implemented without federal standards in place, on a resource-intensive, site-by-site basis. Following settlement of a lawsuit, EPA is now developing national standards in three phases: Phase I for new facilities, Phase II for existing electric generating plants that use large amounts of cooling water, and Phase III for electric generating plants using smaller amounts of cooling water and for manufacturers.

Scope of the Final Rule

This rule applies to new electric generating plants and manufacturers that withdraw more than two million gallons per day (MGD) from waters of the U.S., if they use 25% or more of their intake water for cooling. New facilities with smaller cooling water intakes will still be regulated on a site-by-site basis.

Summary of Requirements

For facilities who choose certainty and fast permitting over greater flexibility, the rule sets standards to limit intake capacity and velocity. Facilities who locate where fisheries need additional protection must use special screens, nets or similar devices. Facilities withdrawing less than 10 MGD are not required to reduce intake capacity, but must use special screens, nets or similar devices if they do not. For facilities who choose to perform site-specific studies, the rule sets a framework for demonstrating that alternative approaches provide comparable protection. All facilities must limit their withdrawals to no more than a defined proportion of their source waterbody.

Impacts and Benefits

The rule is projected to affect 121 facilities to be built over the next 20 years at a total cost of less than $48 million per year. Benefits include a dramatic reduction in mortality or injury of aquatic life at some new facilities and more modest reductions at others.

Additional Information and Copies

For further details regarding this final new facility rule or any other phase of this rulemaking, refer to http://www.epa.gov/waterscience/316b/.

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