In the 1970s, the EPA asked a group of freelance photographers to document the state of America's environment. Called the Documerica project, the photos are a valuable record of the environmental issues that plagued the US in the years before protective legislation like the Clean Air Act and the Clean Water Act. You can see them for yourself on the Documerica Flickr page.
Now, almost 40 years later, the EPA has put out a similar call, asking people to submit photos that document the current 'State of the Environment'. The challenge, which launched last Earth Day, is open to anyone, and you can submit your photos at the project's Flickr page.
As part of the project, the agency also issued a 'Locations' challenge, in which users are asked to pick a photo from the original Documerica project, then "re-shoot" the photo from the same spot.
Photo: Jack Kelly / Flickr