In 2005 Denver Mayor John Hickenlooper joined 49 other mayors nationwide in pledging to improve the environment and living conditions of their cities in an overall effort to reduce greenhouse gas emissions. (By October 2007, 691 mayors nationwide signed this agreement.)

The result was a powerful sustainability initiative called Green Print Denver the mission of which is "to provide leadership and solutions to ensure a prosperous community where people and nature thrive."

Their website, www.greenprintdenver.com provides a wealth of information about the sustainability efforts and follows the most recent achievements.

Habitat for Humanity Recycling by Jessica Reeder

During his time as Mayor, now Governor Hickenlooper could be seen driving around Denver in his official vehicle, a hybrid Ford Escape SUV which is one of 130 vehicles in the city's hybrid green fleet.

• Denver has one of the highest LED traffic light inventories in the country. Light-Emitting Diode traffic signals use 90% less energy and last 5 times longer.
  
  
• 190 million gallons of water are being saved annually thanks to retrofits done by Denver Water partnering with the City of Denver, DPS schools, and Auraria campus.

• Denver has a fee-based composting program for residents. Combined with recycling, Denver residents generate 10lbs less of trash per week.