River ecologists are advocating a broader approach to rescuing damaged rivers, betting that restoring the physical processes that shape a river's habitats will bring back ailing fisheries. Look at the Trinity River as it flows through the heavily forested hills of Northern California's Trinity County, and at many spots you will see what appears to be an idyllic natural scene: flashing water coursing between wooded banks. But to the trained eye of a river ecologist, the sight is not so pretty. Those willows and alders along the river-banks confine the river to a fixed, rectangular channel--a far cry from the shallow and shifting banks typical of a healthy river. And that is only the most outward sign of the transformation that has occurred on the Trinity" since a dam completed in 1963 robbed the river of the winter and spring floods that could send as much as 3000 cubic meters of water per second (m~3/s) churning through the channel. For 20 years after the dam was built, the Trinity lived year-round on a comparative trickle, an unvarying 4 m~3/s released from the dam.
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