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Framework for Chesapeake Bay 
Tidal Waters 303(d) List 
Decision-Making 
BACKGROUND 
Section 303(d) of the Clean Water Act and EPA Regulation 40CFR 130.7 requires 
biennial identification of water segments that are not attaining water quality stan¬ 
dards. These segments must have a total maximum daily load (TMDL) analysis 
completed and allocations established that result in water quality standards attain¬ 
ment. The states comply with this requirement through a process known as the 
Integrated Reporting Requirements which covers the assessment and listing require¬ 
ments through Clean Water Act sections 305(d), 305(b), and 314 (U.S. EPA 2005b). 
Given that the 2006 integrated reporting documents would be the first prepared 
under the states’ newly adopted Chesapeake Bay water quality standards regulations, 
a collaborative effort (among the EPA and watershed states) began in spring 2005 to 
develop a decision-making framework for that portion of the 2006 submittals 
addressing the Chesapeake Bay system. The Chesapeake Bay Program partners 
reached agreement on several key assessment and listing issues. This chapter docu¬ 
ments these agreements and presents the resultant flowchart for Chesapeake Bay 
tidal-water listing decisions to guide Delaware, Maryland, Virginia, and the District 
of Columbia in future 303(d) listing cycles. 
LISTING CATEGORY DECISIONS 
Each state-adopted, tidal-water designated use by Chesapeake Bay Program segment 
(or formally adopted state sub-segment) is considered an individual spatial assess¬ 
ment unit for the purposes of each state’s 303(d) list (U.S. EPA 2003a, 2003b, 2004a, 
2004b, 2005a). 
If a segment has been previously listed in category 5—recognizing the recent adop¬ 
tion of new Chesapeake Bay water quality standards—the original listing decision 
chapter viii 
Framework for Chesapeake Bay Tidal Waters 303(d) List Decision-Making 
