The Santa Ana River is a robust and beautiful sight these days. Five miles west of the Prado Dam in Yorba Linda, the water has cut a narrow channel in a sandy bed and courses briskly over submerged rocks and tree limbs.
The water is a complicated cocktail that comes from many sources. As it flows 96 miles from its headwaters to the ocean, it provides a glimpse of the future: a picture of water management set into place nearly 50 years ago that can be seen as a model for California's long effort to keep the state from withering away.