Doing away with dams
Dams aren't the infrastructure darlings they once were. Since 1999, 430 dams have come down, according to the American Rivers environmental group. The reasons are largely economic: Maintenance is high as the concrete walls age. Also, power needs can be supplied by other sources. The decline of migrating salmon and steelhead are also a factor.
These problems don't mean all dams are doomed or new ones will never be built. Dam defenders note that ...
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Irrigation/hydro-electric dams have two purposes. One is to create head to enable water to be sent down irrigation pipes or down generator com-stocks. The other is to even out the water flow so water is available at times of low flow. Head can be created without a dam by taking water from a small weir a little further up stream down a canal and dropping it back into the river through a generator further down stream. Even flow can be achieved by making sure that the headwaters of your catchment are fully stocked with beavers. See Three Against the Wilderness by Eric Collier for an account of the change in the hydrology when beavers were introduced into Meldrum Creek