You can read the whole ruling here:
Orff v. United States, 545 U. S. ___ (2005)
R072; No. 03-1566; 6/23/05. In enacting a provision of the Reclamation Reform Act of 1982, 43 U. S. C. §390uu, Congress did not waive the United States' sovereign immunity from a breach of contract suit brought by petitioners, who purchase water from a local water district that receives its water, pursuant to contract, from the United States Bureau of Reclamation.
Thanks!!