Aterciopelados' album "Rio", released October 21, 2008, coincides with a proposed Colombian constitutional referendum that declares that access to water is a fundamental right for all Colombians and provides for maintenance and preservation rights. "When I was growing up, the Bogotá River was considered a mythic and iconic place, and now it's a tiny stream," says Echeverri. With "Rio", Aterciopelados takes an increasingly forceful stand on the environment. Buitrago notes, "While on previous albums, we may have simply declared many of the world's problems, we now strive to work in a more active way. In this case, it is with the recovery of Bogotá's river, as it is one of the most polluted rivers in the world."