Green roofs play an important role in Portland's water story. They improve the sustainability of our urban environment because they reduce building energy use; capture stormwater, preventing excess rainwater from entering our over-taxed water infrastructure; combat the urban heat island effect; and create habitat for insects and birds. Multnomah County was the first public agency to build a green roof on a municipal building in the Portland metropolitan area.

In 2001, Multnomah County officials had to replace a leaking 12,000 square-foot flat roof on its headquarters building. The green roof approach won widespread support after a cost analysis revealed long-term savings over a conventional roof. Plus, the team realized a green roof would be of great educational value as a demonstration project. Grants from the Portland's Bureau of Environmental Services, Portland State University, and the Oregon Department of Environmental Quality provided financial support to the eco-roof.

Completed in July 2003, the rooftop meadow and garden is enjoyed by both government employees and the general public. The eco-roof has been a model for other public and private installations; it's an excellent example of an extensive green roof that has stood the test of time. In contrast to intensive green roofs, which allow for deeper amounts of soil and even trees to be planted, extensive roofs are shallow and often filled with sedum or grasses.

The green roof project was designed by landscape architect Macdonald Environmental Planning, Carleton Hart Architecture, and Marie-Anne Boivin, a green roof consultant. Tom Liptan, FASLA, a landscape architect with the city government, can be credited with commencing the green roof movement and regulatory process in Portland, initially based on research on his own garage eco-roof in 1996.