Document ID: ./input/supremecourt_opinions/opinions/22pdf/21-1484_aplc.pdf
Page Number: 28.0

Cite as:  599 U. S. ____ (2023) 

7 

GORSUCH, J., dissenting 

into  farmers.  They  must  pass  through  the  intermediate 
stage of herdsmen.  They must first become pastoral, then
agricultural.’ ”  Id., at 269. 

Despite all this, “[f]or the Navajos the treaty signified not 
defeat,  but  victory,  and  not  disappearance,  but  continua-
tion.”  Iverson 36.  “The agreement allowed [them] to return
to a portion of their home country.”  Ibid.  Nor would that 
“portion” remain so confined.  The Navajo often struggled
to stay on the narrow tract of land the United States pro-
vided.  Commission Report 9.  In practice, the federal gov-
ernment  often  tolerated  (and  sometimes  encouraged)  the
Navajo to live and tend to livestock off reservation to pre-
serve  their  self-sufficiency.  Kessell  271.  These  arrange-
ments continued until the 1930s, when Congress first “en-
act[ed]  legislation  defining  the  exterior  boundaries  of  the 
Navajo  Reservation.”    Id.,  at  272.  Over  the  ensuing  dec-
ades,  Congress  would  go  on  to  extend  the  reservation’s 
boundaries repeatedly.  See, e.g., Act of June 14, 1934, 48 
Stat. 960; Act of Feb. 21, 1931, ch. 269, 46 Stat. 1204; Act of 
May 23, 1930, ch. 317, 46 Stat. 378. 

C 
Fast forward to the present.  Today, the Navajo Reserva-
tion  has  become  “the  largest  Indian  reservation  in  the
United  States,”  with  over  “17  million  acres,”  and  over 
“300,000 members.”  App. 90.  Its western boundary runs
alongside a vast stretch of the Colorado River.  Id., at 91. 
Yet even today, water remains a precious resource.  “Mem-
bers of the Navajo Nation use around 7 gallons of water per 
day for all of their household needs”—less than one-tenth 
the amount the average American household uses.  Id., at 
101.  In some parts of the reservation, as much as 91% of 
Navajo households “lack access to water.”  Id., at 102. 

That deficit owes in part to the fact that no one has ever 
assessed  what  water  rights  the  Navajo  possess.    For  in-
stance,  “[a]lthough  the  Navajo  Reservation  is  adjacent  to