Conservationists in California and across the West are deeply skeptical of hydropower, and it’s not hard to see why. There’s a long history of government agencies damming spectacular canyons, choking off rivers, obliterating fish populations and cutting off access to Indigenous peoples. It’s a history detailed in books such as “Cadillac Desert,” and experienced by anyone who has spent time fishing, kayaking or swimming in the region’s reshaped waterways, or hiking alongside them.