Section 316 of the Clean Water Act

316(a) Thermal Regulations

Section 316(a) of the Clean Water Act regulates heated discharges into waters of the United States. EPRI held a workshop in 2003 intended to provide participants with an overview of technical and regulatory issues and considerations concerning Section 316(a): Effects database; water quality criteria issues; strategies for 316(a) variances; instream assessment of thermal effects; permitting; cooling technologies; trading; and TMDL considerations. The workshop was intended to provide a forum for information exchange among participants, presentation of case studies, and an update on the current knowledge of thermal physiology and thermal effects. PPRP participated in the workshop by presenting a paper on evaluation of thermal discharges in Maryland. Relevant Documents 1977 EPA 316(a) Technical Guidance Manual (6 MB pdf file) Overview of CWA Section 316(a) Evaluations of Power Plants with Thermal Discharges in Maryland (5.1 MB powerpoint) Overview of CWA Section 316(a) Evaluations of Power Plants with Thermal Discharges in Maryland (15.9 MB word document) 316(b)Cooling Water Intake Structure Regulations EPA developed new regulations under section 316(b) of the Clean Water Act that are of great significance to the owners and operators of many power plants within Maryland, and also to electricity consumers within our state. Section 316(b) requires that the location, design, construction and capacity of cooling water intake structures reflect the best technology available (BTA) for minimizing adverse environmental impact. The withdrawal of cooling water has the potential to cause environmental impacts due to impingement and mortality of organisms, primarily fish, on screens that protect the intake system, and through entrainment and mortality of small organisms, primarily fish eggs and larvae, that pass through those screens and through the plant’s entire cooling system. Development of the new regulations is taking place in three phases: Phase I, which was completed in late 2001, applied to new facilities. Phase II, which was issued in February 2004, consists of regulations applicable to existing large facilities, defined as those withdrawing more than 50 million gallons of cooling water per day (mgd). Phase III consists of regulations applicable to small existing facilities (i.e., those that withdraw less than 50 mgd). In January 2007, the U.S. 2nd Circuit Court of Appeals decided in Riverkeeper, Inc., v. EPA that many parts of the Phase II rule were invalid or needed to reevaluated by EPA. Thus, as of March 20, 2007, the Phase II rule was suspended. See links below for further details. Consequences for Maryland Power Plants US EPA's 316(b) website Relevant Documents 1977 EPA Guidance for Evaluating the Adverse Impacts of Cooling Water Intake Structures on the Aquatice Environment - May 1, 1977 (139 KB pdf file) Phase 1 Notice of Data Availability (NODA) - May 25, 2001 (121 KB pdf file) PPRP comments on Phase 1 NODA (Coming Soon) Phase 1 (New Facilities) Final Rule - Dec 18, 2001 (776 KB pdf file) Maryland Power Plant Cooling Water Intake Regulations and their Application in Evaluation of Adverse Environmental Impacts - March 2002 (1.1 MB pdf file) Phase 1 (New Facilities) Amendment to Final Regulations - June 19, 2003 (56 KB pdf file) Phase 2 proposed rule - April 9, 2002     Part 1 (315 KB pdf file)     Part 2 (568 KB pdf file)     Part 3 (51 KB pdf file) PPRP comments on Phase 2 proposed rule Phase 2 Notice of Data Availability (NODA) - March 19, 2003 (427 KB pdf file) Presentation of State of Maryland Perspectives on Cooling Water Intake Technologies to Protect Aquatic Organisms - May 6, 2003 (3.3 MB) powerpoint file) (Pre-publication manuscript 1.8 MB)Word file PPRP comments on Phase II NODA - June 2, 2003 (1.5 MB pdf file) Phase 2 final rule - link to EPA 2nd Circuit Court of Appeals decision in Riverkeeper, Inc., v. EPA (250 KB pdf file) EPRI 316(b) Phase II Rule Litigation Decision Summary (69 KB Word file) Return to the Power Plant Research Program ActivitiesPage Return to the Maryland DNR Home Page Return to the Power Plant Research Program Page This page was updated on April 11, 2007 .