Document ID: ./input/supremecourt_opinions/opinions/22pdf/21-454_4g15.pdf
Page Number: 25

Cite as:  598 U. S. ____ (2023) 

19 

Opinion of the Court 

United States.”  The provision begins with a broad category,
“the waters of the United States,” which we may call cate-
gory A.  The provision provides that States may permit dis-
charges into these waters, but it then qualifies that States
cannot  permit  discharges  into  a  subcategory  of  A:  tradi-
tional navigable waters (category B).  Finally, it states that
a third category (category C), consisting of wetlands “adja-
cent” to traditional navigable waters, is “includ[ed]” within
B.  Thus,  States  may  permit  discharges  into  A  minus  B,
which includes C.  If C (adjacent wetlands) were not part of
A (“the waters of the United States”) and therefore subject 
to  regulation  under  the  CWA,  there  would  be  no  point  in
excluding them from that category.  See Riverside Bayview, 
474 U. S., at 138, n. 11 (recognizing that §1344(g) “at least 
suggest[s] strongly that the term ‘waters’ as used in the Act
does  not  necessarily  exclude  ‘wetlands’ ”);  Rapanos,  547 
U. S.,  at  768  (opinion  of  Kennedy,  J.).    Thus,  §1344(g)(1) 
presumes  that  certain  wetlands  constitute  “waters  of  the
United States.” 

But  what  wetlands  does  the  CWA  regulate?    Section 
1344(g)(1) cannot answer that question alone because it is 
not  the  operative  provision  that  defines  the  Act’s  reach. 
See Riverside Bayview, 474 U. S., at 138, n. 11.  Instead, we 
must  harmonize  the  reference  to  adjacent  wetlands  in
§1344(g)(1)  with  “the  waters  of  the  United  States,” 
§1362(7), which is the actual term we are tasked with inter-
preting.  The formulation discussed above tells us how: be-
cause the adjacent wetlands in §1344(g)(1) are “includ[ed]” 
within  “the  waters  of  the  United  States,”  these  wetlands 
must qualify as “waters of the United States” in their own 
right.  In other words, they must be indistinguishably part
of a body of water that itself constitutes “waters” under the
CWA.  See supra, at 14. 

This understanding is consistent with §1344(g)(1)’s use of
“adjacent.”    Dictionaries  tell  us  that  the  term  “adjacent”
may  mean  either  “contiguous”  or  “near.”    Random  House