U.S. Interior Secretary Gale Norton said yesterday that she had the legal authority to release a small amount of irrigation water for farmers to use in the Klamath Basin on the Oregon-California border. All irrigation water from Upper Klamath Lake has been cut off since April to protect endangered suckerfish and threatened coho salmon. Farmers in recent weeks have tried four times to get water to flow illegally into an irrigation canal, forcing federal law-enforcement officers to intervene. Farmers said Norton’s decision to release water as soon as today would do little good for their crops this season, and environmentalists said the move violated the Endangered Species Act.