Tens of thousands of acres in Oregon's drought-stricken Klamath Basin will have to go without irrigation water this summer after the Klamath Tribes and the federal government exercised for the first time newly confirmed powers that put the American Indian tribes in the driver's seat over the use of water.

Klamath Tribes Chairman Don Gentry and U.S. Bureau of Reclamation Commissioner Mike Connor said Monday they were making what is known as a "call" on their water rights for rivers flowing into Upper Klamath Lake in Southern Oregon.

The new powers were made possible by a March ruling of an administrative law judge confirming the tribes have the oldest water rights in the upper basin, and therefore first say over controlling it. The bureau's rights date to 1905.