How water pipes, subway trains, and sewage treatment can provide clean power to the city above.
Sorry, beavers. Hydrologists trying to improve conditions for fish just don't need you anymore.
Rx for veterans with post-traumatic stress: Get out into the wild.
Tom Turner chronicles how the former Sierra Club executive director's insight and activism stimulated the evolution of an entire movement.
Moroccan goats engage in our favorite form of old-school environmentalist protest.
Space lettuce and meatless meat—food has arrived at the next frontier.
It's good and it's bad—Aspen goes 100% renewable, but Alaskans are paying $10 for milk.
Starting September 12, over 170 events will be hosted across the United States and Canada.