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Regulatory Development and Retrospective Review Tracker

Criteria and Standards for Cooling Water Intake Structures

a.k.a. Section 316(b) Cooling Water Intake Existing Facilities Rule

RIN: 2040-AE95 (What's this?)

Docket No.: Not yet available (What's this?)

Current Phase: Proposal (What's this?)

Section 316(b) of the Clean Water Act (CWA) requires the EPA to ensure that the location, design, construction, and capacity of cooling water intake structures reflect the best technology available (BTA) for minimizing adverse environmental impacts. Under a consent decree with environmental organizations settling a lawsuit, the EPA divided the 316(b) rulemaking into three phases.

All new facilities except offshore oil and gas exploration facilities were addressed in Phase I in December 2001. In July, 2004, the EPA promulgated Phase II which covered large existing electric generating plants. In July 2007, the EPA suspended essentially all of the Phase II rule following a decision in the U.S. Court of Appeals for the Second Circuit that remanded elements of the rule to the EPA. Several parties petitioned the U.S. Supreme Court to review that decision, and the Supreme Court granted the petitions, limited to the issue of whether the Clean Water Act authorized the EPA to consider the relationship of costs and benefits in establishing 316(b) standards. On April 1, 2009, the Supreme Court reversed and remanded the case to the Second Circuit. The Second Circuit subsequently granted a request from the EPA that the case be returned to the Agency for further consideration. In June 2006, the EPA promulgated the Phase III regulation, covering existing electric generating plants using less than 50 MGD of cooling water, new offshore oil and gas facilities, and all existing manufacturing facilities. Petitions to review this rule were filed in the U.S. Court of Appeals for the Fifth Circuit. In July 2010, the U. S. Court of Appeals for the Fifth Circuit issued a decision upholding the EPA's rule for new offshore oil and gas extraction facilities. The court also granted the request of the EPA and environmental petitioners to remand the existing facility portion of the rule to the Agency. The EPA entered a settlement agreement with the plaintiffs in two lawsuits concerning the Section 316(b) rulemakings. Under the settlement agreement, the EPA agreed to sign a notice of a proposed action and , notice of a final decision pertaining to issuance of requirements for implementing section 316(b) of the CWA at existing facilities After a number of subsequent modifications to the settlement agreement, the EPA and the plaintiffs agreed that a notice of proposed rulemaking would be signed by March 28, 2011 and of a final decision would be signed by January 14, 2014. In these settlement agreements plaintiffs agreed to seek dismissal of both their suits, subject to a request to reopen one of the lawsuits in the event that the EPA failed to meet the deadlines. The EPA's proposed regulation includes standards for all existing facilities to prevent fish from being trapped against screens (impingement) and for existing facilities and new units at existing facilities to prevent fish from being drawn through cooling systems (entrainment). The EPA issued two Notices of Data Availability in June 2012 that described measures to provide additional flexibility that EPA was considering for the impingement mortality standard and that described the preliminary results of surveys of households' willingness to pay for incremental reductions in fish mortality. In light of the Supreme Court 2009 decision and its recognition that the EPA has broad discretion in what factors to consider in developing its 316(b) regulations, the EPA initiated consultation with the Fish and Wildlife Service and the National Marine Fisheries Service under Section 7 of the Endangered Species Act. EPA and the Services began informal consultation in 2012, and concluded in 2013 that formal consultation was necessary.

NPRM: Sent to OMB for Regulatory Review02/11/2011
NPRM: Received by OMB02/14/2011
NPRM: Regulatory Review Concluded03/28/2011
NPRM: Comment Period Open04/20/2011
NPRM: Published in FR04/20/2011
NPRM: Comment Period Closed07/19/2011
NPRM: Comment Period Extension Published in FR07/20/2011
NPRM: Comment Period Closed with Extension08/18/2011
NODA: Sent to OMB for Regulatory Review01/19/2012
NODA: Received by OMB01/25/2012
NODA: Regulatory Review Concluded05/31/2012
NODA: Published in FR06/11/2012
NODA: Published in FR06/12/2012
Final Rule: Sent to OMB for Regulatory Review07/26/2013
Final Rule: Received by OMB07/30/2013
Final Rule: Regulatory Review Concluded05/19/2014
Final Rule: Published in FR07/2014 (projected)

Potential Effects

Federal Government - other agencies
Likely to be regulated by this rule.
Likely to be involved in the implementation of this rule.

Local Governments
Likely to be regulated by this rule.

Small Entities
EPA notifies the public when a rulemaking is likely to 1) have any adverse economic impact on small entities even though a Regulatory Flexibility Analysis may not be required and/or 2) have significant adverse economic impacts on a substantial number of small entities. The term "small entities" includes small businesses, small governments, and small not-for-profits. (Read a longer explanation on our Small Entities web page.) This rulemaking is likely to impact small entities in the following way(s):
  • Likely to have any adverse economic impact on:
    • small businesses

In addition, small governments are:

  • Likely to be regulated by this rule.

State Governments
Likely to be involved in the implementation of this rule.

Unfunded Mandates
This action may place unfunded mandates on the private sector and is subject to Section 202 of the Unfunded Mandates Reform Act.

Participate / Learn More Regulatory Review

Some of EPA's rulemakings undergo regulatory review (What's this?), as prescribed by Executive Order 12866 and coordinated by the Office of Management and Budget (OMB). The following list describes which of this rulemaking's stages have completed review and published in the Federal Register, if any, and provides links to the review documents where available. Consult the "Timeline" section of this Web page for the dates of each review.

  • Final Rule - No Information Available.
  • Final Rule - This stage of the rulemaking underwent review.
  • NODA - This stage of the rulemaking underwent review.
  • Final Rule - No Information Available.
Citations & Authorities

Federal Register Citations

Code of Federal Regulations (CFR) Citation
40 CFR 122 40 CFR 125

Legal Authority
CWA 101 CWA 301 CWA 304 CWA 308 CWA 316 CWA 401 CWA 402 CWA 501 CWA 510


This site provides summaries of priority rulemakings and priority retrospective reviews of existing regulations. We update most of the site at the beginning of each month, though some data is updated more frequently if it is time sensitive. The information on this site is not intended to and does not commit EPA to specific conclusions or actions. For example, after further analysis, EPA may decide the effects of a rule would be different or it may decide to terminate a rulemaking.

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