Document ID: ./input/supremecourt_opinions/opinions/22pdf/21-454_4g15.pdf
Page Number: 80

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

13 

KAVANAUGH, J., concurring in judgment 

22307;  88  Fed.  Reg.  3095,  3118.  Similarly,  artificial
barriers such as dikes and levees typically do not block all 
water  flow,  85  Fed.  Reg.  22312;  88  Fed.  Reg.  3076,  and 
those  artificial  structures  were  often  built  to  control  the 
surface  water  connection  between  the  wetland  and  the 
water.  85  Fed.  Reg.  22315;  88  Fed.  Reg.  3118.  The 
scientific  evidence  overwhelmingly  demonstrates  that 
wetlands separated from covered waters by those kinds of
berms or barriers, for example, still play an important role
in  protecting  neighboring  and  downstream  waters, 
including  by  filtering  pollutants,  storing  water,  and
providing  flood  control.    See  88  Fed.  Reg.  3118;  33  CFR 
§320.4(b)(2)  (2022);  see  also  United  States  v.  Riverside 
Bayview Homes, Inc., 474 U. S. 121, 134 (1985).  In short, 
those  adjacent  wetlands  may  affect  downstream  water
quality  and  flood  control  in  many  of  the  same  ways  that
adjoining wetlands can.

The Court’s erroneous test not only will create real-world
consequences for the waters of the United States, but also
is  sufficiently  novel  and  vague  (at  least  as  a  single 
standalone test) that it may create regulatory uncertainty
for  the  Federal  Government,  the  States,  and  regulated 
parties.  As  the  Federal  Government  suggests,  the
continuous surface connection test raises “a host of thorny
questions” and will lead to “potentially arbitrary results.” 
Brief for Respondents 29.  For example, how difficult does
it have to be to discern the boundary between a water and 
a wetland for the wetland to be covered by the Clean Water
Act?  How  does  that  test  apply  to  the  many  kinds  of
wetlands  that  typically  do  not  have  a  surface  water 
connection  to  a  covered  water  year-round—for  example,
wetlands  and  waters  that  are  connected  for  much  of  the 
year  but  not  in  the  summer  when  they  dry  up  to  some
extent?  How  “temporary”  do  “interruptions  in  surface 
connection”  have  to  be  for  wetlands  to  still  be  covered? 
Ante,  at  21.  How  does  the  test  operate  in  areas  where