Beavers are back on California's Salinas River

Nature's engineers are making a comeback on the Salinas River, with new beaver dams boosting groundwater, improving water quality, and building drought resilience — funded in part by pollution penalties paid by PG&E. Once treated as pests, beavers are now recognized as some of the cheapest, hardest-working restoration crews around. The river's furriest builders are back on the job.