Document ID: ./input/supremecourt_opinions/opinions/boundvolumes/558bv.pdf
Page Number: 432

Cite as: 558 U. S. 256 (2010) 

271 

Opinion of the Court 

as  Lancaster  County 6—should  receive  less  water.  See  Tr. 
of  Oral  Arg.  52  (“From  North  Carolina’s  perspective, 
South Carolina is receiving much more water under this ne­
gotiated  agreement  than  they  could  ever  hope  to  achieve  in 
an equitable apportionment action”).  The stresses that this 
litigation  would  place  upon  the  CRWSP  threaten  to  upset 
the ﬁne balance on which the joint venture is premised, and 
neither  State  has  sufﬁcient  interest in  maintaining  that  bal­
ance  to  represent  the  full  scope  of  the  CRWSP’s  interests. 
Accordingly,  we  believe  that  the  CRWSP  should  be  al­
lowed  to  intervene  to  represent  its  own  compelling  inter­
ests  in  this  litigation.  We  thus  overrule  South  Carolina’s 
exception. 

2 

We conclude, as well, that Duke Energy has demonstrated 
powerful interests that likely will shape the outcome of this 
litigation.  To  place  these  interests  in  context,  it  is  instruc­
tive to consider the “ﬂexible” process by which we arrive at a 
“ ‘just and equitable’ apportionment” of an interstate stream. 
Colorado v.  New Mexico, supra, at 183.  We do not approach 
the  task  in  formulaic  fashion,  New  Jersey  v.  New  York,  283 
U. S., at 343, but we consider “all relevant factors,” including, 
but not limited to: 

“ ‘physical  and  climatic  conditions,  the  consumptive  use 
of water in the several sections of the river, the charac­
ter  and  rate  of  return  ﬂows,  the  extent  of  established 

6 As a further complication, we are told, Lancaster County has an obliga­
tion to provide water service to certain customers in Mecklenburg County, 
North Carolina.  CRWSP Reply 6.  Thus, South Carolina may not be in­
terested  in  protecting  all  uses  of  Lancaster  County’s  share  of  the 
CRWSP’s water.  This additional intermingling of state interests further 
supports  our  conclusion  that  neither  State  adequately  represents  the 
CRWSP’s inherently bistate interests.