In recent days, a new garden has taken root in downtown Denver. Didn’t see it?
Look up. Way up.
About 27,000 plants – dragon’s blood and red carpet among them – are growing on the multitiered roof at the U.S. Environmental Protection Agency’s new regional headquarters at Wynkoop and 16th streets.
The roof is Colorado’s first “green roof” and is designed to insulate the building and help reduce the amount of rainwater that hits the streets.
Typically, water that hits flat surfaces such as roads and roofs picks up dirt, debris and chemicals before trickling into nearby streams – creating water pollution headaches for urban cities.
“We really think green roofs are the wave of the future and hope the EPA project will highlight its benefits,” said Amy Javernick Will, project manager for Opus Northwest, the building’s owner.
The plants, drought tolerant and native to Colorado, grow in 4-inch-deep pallets made of recycled plastic.
For two years, Opus will water them using a drip irrigation system. After that, the plants will be on their own.
The pallets, made by Weston Solutions, are designed to retain about 60 percent of the water they catch. The rest is filtered through the pallets and piped through the building.
Javernick Will said the pallets were chosen over some of the older green-roof designs that are constructed in layers, starting with a waterproof membrane, a drainage layer, then insulation, root barriers and soil.
Those roofs can be tricky to repair, she said.
“As a building owner, we were looking toward an advanced technology that if we have a leak, we can fix it quickly,” Javernick Will said.
The roof is one of many “green” features of the EPA building, including solar panels, wind turbines and a nine- story atrium designed to increase natural lighting and reduce the energy load.
The design has been used extensively throughout Europe and in Milwaukee; Boise, Idaho; and Portland, Ore.
The roof design is prevalent in Chicago, where the City Council has adopted a policy that encourages – and sometimes requires – green roofs to be installed on new buildings.
In Dearborn, Mich., Ford Motor Co. installed a green roof four years ago at a truck assembly plant.
Today, killdeer have begun laying eggs on top of the roof, which has now survived several harsh winters.
“We really haven’t had a lot of issues,” said Don Russell of Ford’s environmental quality department. “No leaks, no problems with runoff, and it’s required minimum maintenance.”
Recently, a delegation from Steamboat Springs toured the EPA building in Denver to learn more about its green roof.
City of Denver officials say they are also fielding questions from developers.
“The city is definitely taking the tack of working with the development community to find strategies that work for them and work for us,” said Rob Duncanson, director of the city’s development engineering services.
Staff writer Kim McGuire can be reached at 303-954-1240 or kmcguire@denverpost.com.
