TUSKAHOMA, Okla. — Sardis Lake, a reservoir in southeastern Oklahoma young enough to have drowned saplings still poking through its surface and old enough to have become a renowned bass fishery, is not wanting for suitors.

Oklahoma City and fast-growing suburbs like Edmond want to see the water flowing through their shower heads someday. So do the water masters of Tarrant County, Tex., 200 miles to the south, who are looking to supply new subdivisions around Fort Worth and are suing for access.

Now another rival has arrived: the Choctaw and Chickasaw tribes, who were exiled to southeastern Oklahoma 175 years ago and given land in the area.

Gregory Pyle, chief of the Choctaw nation, said his tribe would sue to win some of the water if necessary. “All this water was controlled originally by the Indian tribes in this area,” Mr. Pyle said. “It is all Choctaw and Chickasaw water.”