The Los Angeles River has something of a forsaken past. For decades, the federal government considered it a piece of infrastructure no different than a sewage grate, and most people only knew it as the dirty concrete half-pipe that occasionally appeared in Hollywood movies as a symbol of L.A.‘s artifice. But thanks a coalition of activists and their various efforts to call attention to the river, this 51-mile natural resource — the very thing that attracted settlers to the region in the first place — has finally earned back some visibility. The EPA gave it legitimacy as an actual river three years ago, thanks to this fierce coalition of environmentalists, urban adventurers and residents. Now, the grassroots vision of a people’s waterway has become official city policy. Los Angeles-based writer Nate Berg looks back at the history of the river, from its role in turning Southern California into an agricultural mecca 150 years ago to 20th-century proposals to build freeways on its riverbed, to find how its unlikely rebirth came about.