Prairie flowers sway atop Mercy Health – West Hospital

October 15, 2013

Many-colored stalks of wildflowers bob in steady breeze. Hidden birds trill and call. Dragonflies hum through rustling prairie grass.

Mercy Health – West Hospital, scheduled for opening Nov. 10, has brought the natural tranquility of a Midwestern prairie to its campus with a 2.5-acre "green" roof. The landscaping offers a sense of peace to patients and visitors at the new hospital in Cincinnati.

The green roof covers the emergency department, operating rooms and other services on the $250 million, 240-bed hospital's expansive main floor. The L-shaped tower of patient rooms rises amid the greenscaping, affording an unobstructed view of the waves of grasses and wildflowers.

Michael Stephens, market leader and president of Mercy Health – West Market, said that "a serene environment is an important component of our patients' recovery and the well-being of our visitors, employees, physicians and wider community." The prairie theme extends to the outer lawns and entrance drives, as well.

Gary Meisner, the landscape architect whose company designed the green roof, said Mercy Health sought a durable covering that would outlast a standard roof membrane, reduce rainwater runoff from the hospital campus and provide the peaceful vista for patients and visitors.

"Too often, an ailing patient looks out of the room, seeking to connect with God, and sees mechanical equipment stacked upon a roof," said Meisner, of Cincinnati. "The idea was to provide a sense of the ancient Midwestern prairie. We approached the design and colors of the landscape as would an artist with a mural."

Mercy Health drew inspiration from a green roof at its sister hospital, Springfield Regional Medical Center in west-central Ohio. Meisner's firm also designed that roof, which covers about one acre and was installed three years ago. Springfield's was the largest green roof in Ohio until construction of the new one at Mercy Health – West Hospital, which is eight miles northwest of downtown Cincinnati.

Meisner said the design incorporates native plants that can thrive in relatively arid conditions. He said there are fittings for sprinklers on the roof that can be used in times of extreme drought, but no extensive and expensive irrigation system.

Running through the landscape are curving berms, or prairie swirls, about 18 additional inches high to provide sufficient soil for the most colorful of the plants. The results are thick bands of purple, red, yellow and blue running through the hardier, shorter, tundra-like plants covering a shallower growing medium.

Most of the landscape is across the wide main roof of the first floor, but some of it wraps around the west patient wing. There's also a piece of prairie near the therapy terrace, and a more ornamental, thicker green roof atop the hospital chapel.

All told, the green covering consists of more than 64,000 plants. Most of them are hardy, low-growing sedums. But there are 14,000 prairie plants with flowers of many bright colors planted along the berms, including the ornamental perennials bee balm, little bluestem, prairie dropseed, butterfly weed and obedients.

Meisner said the architects worked with the structural engineers to concentrate necessary mechanical works in a few places on the landscaped roof, both to improve the view and limit the potential for leaks. He said the membrane's chemistry prevents roots from trying to grow through it.

A special growing medium is used in lieu of top soil; it's spread about six inches deep across the roof membrane. The growing medium is a patented product that Meisner said is roughly similar to a mix of potting soil, peat moss and dehydrated clay, and is significantly lighter than regular topsoil. It's also more expensive — about $100 per cubic yard compared to $20 for the same volume from the neighborhood dirt hauler. But he said the special medium absorbs and holds water well, which is good for the plants and for the hospital's storm water bill.

The hospital's green roof can retain almost 200,000 gallons of water, or about one-third of the volume of a filled Olympic-sized pool. Meisner said that the roof will significantly reduce the campus runoff volume during a rainstorm.

He said the roof membrane also can last more than twice as long the standard version that bakes in the summer and freezes in the winter. And he said it provides better insulation for the hospital operations beneath it than standard fiberglass products that are stuffed above ceilings.

Nanette Bentley, director of public relations for Mercy Health in Cincinnati, said administrators have been pleased with the green roof at Springfield Regional. Bentley said they believe the additional cost of installing the green roof in Cincinnati will be offset by savings in heating, cooling and reduced storm-water runoff.

She said the green roofs "provide something beautiful and peaceful for our patients and their families to feast their eyes upon."


Copyright © 2013 by the Catholic Health Association of the United States
For reprint permission, contact Betty Crosby or call (314) 253-3477.

Copyright © 2013 by the Catholic Health Association of the United States

For reprint permission, contact Betty Crosby or call (314) 253-3490.