By Janet Goetze
David Delk is a volunteer for a city program that controls stormwater, provides attractive streetscapes and adds natural habitat for some creatures.
Best of all, Delk said, his basement no longer floods.
He is one of about 60 Green Street Stewards who watch over small “rain gardens” being installed along city curbs to handle run-off from rain storms.
The city is seeking more volunteers, working singly or in groups, to keep trash and leaves from clogging the points where water flows into the curbside plantings. This Green Street infrastructure uses stormwater as a resource instead of sending it straight into a sewer pipe, said Emily Hauth, manager of Portland’s Sustainable Stormwater Program.
The plants and soil filter pollutants that the rain washes from the streets, Hauth said. In addition, the miniature gardens keep Portland’s older pipe system from becoming overwhelmed in heavy rains. Decades ago, sewer and stormwater customarily used the same pipe. As more of the city develops and paving increases, the runoff increases, too.
Delk knows about that. His house sits in a low point of Northeast 45th Avenue, north of Burnside Street. In heavy rains, he was finding water in his basement. After complaints to the city, engineers suggested a Green Streets program as a remedy.
Because the special planted areas absorb rain water and hold it for a slow release, Delk didn’t have excess water seeping into his basement in the rainy weather earlier this year, he said.
Construction on the concrete forms, which hold soil and plantings, began in early spring and were completed in June. Delk and his neighbors selected many of the plants for the rain garden from a list of flowers and shrubs that do well in both wet and dry environment. His include a low-growing Oregon grape, tall grasses and Douglas iris. The city’s list of approved plants also includes coastal strawberry, Kelsey dogwood, slough sedge (carex obnupta) and spreading rush (juncus patens).
Delk, who recently retired from an office job, signed up to be a Green Street Steward because he enjoys gardening and liked the idea of an environmentally friendly way to solve stormwater problems. In a basic training class, he learned that he shouldn’t add any plants to his rain garden. That guards against invasive species being introduced and makes sure that everything is likely to survive in this climate.
Hauth also asks stewards to refrain from weeding for at least two years, to make sure they don’t inadvertently pull up desired plants. After the plants are well established, stewards will have refresher training that includes tips for removing weeds, she said.
During the first two years, city contractors water the rain gardens in dry weather. Stewards are asked to provide supplemental watering in hot weather between contractors’ visits and to clear trash and leaves. They may push aside any sediment building up at the water entry, Hauth said, but the contractors will remove the silt.
In a training class attended by Sandra Dudley, a Laurelhurst neighborhood resident, Hauth advised against working in a rain garden during high traffic hours. She suggested wearing a bright safety vest and working from the sidewalk as much as possible. Dudley, who likes gardening, said she frequently walks past the rain garden for which she will register as a steward. She also will record online how often she tends the garden and what activities she performs.
“I think they are fascinating,” she said of the rain gardens, which landscape architects design. “They are very professionally done. It’s a really attractive and functional solution (to stormwater overflow).”
Portland began constructing its 1,200 Green Streets facilities throughout the city in 2003. One of the largest concentrations is between the Mt. Tabor neighborhood and the Willamette River, Hauth said. Others are in the Cully neighborhood, along New Columbia Avenue and North Denver Avenue in the Kenton business district. More are being installed on Morris, Siskiyou and Klickitat streets between North Vancouver and Northeast 67th Avenue.
Portland’s program is attracting interest across the country and even from foreign countries, Hauth said, including Finland, Sweden, United Kingdom, Russia, China and Korea.
For more information: Green Street Stewards, portlandonline.com/bes/GreenStreetSteward, firstname.lastname@example.org, (503) 823-5623