As a project to raise awareness, the rain garden at the intersection of First and Spring streets has been a success. As a pollution filtration system to be applied on a larger scale? Not so much.
“It was a test case. No one knew how effective it would be,” Friday Harbor Administrator Duncan Wilson said. “We’ve never seen any results that indicated a significant benefit,”
So, the town has other ideas to help curb pollution from storm water runoff.
Four years ago, local businessman and San Juan County Marine Resources Committee member Johannes Krieger, had an idea of his own.
Enter the rain garden, a low-impact way to reduce chemicals in storm water runoff through use of specific soils and plants that together act as a filtration system.
Rather than a cure-all for the town’s storm water woes, the rain garden, as proposed, was intended as a model. If applied on a larger scale, it would demonstrate how pollutants in water runoff might be reduced before reaching the front drain of the harbor.
The call for rain gardens
Rather than a curb extension, the Town Council instead accepted, in 2011, the MRC proposal to install a rain garden at that intersection. Funded by a $35,000 grant from the state Department of Ecology, the project included excavating the corner, installing a planter box, and filling the garden with appropriate soil and plants. The grant also called for a study of its effectiveness.
“Several people wanted the town to do this and to get the MRC to take it on,” Krieger said. “Finally, after me hearing about it for a year and a half, it seemed like it wasn’t going anywhere.”
With some prodding and patience, Krieger was able to get the garden somewhere, outside of Herb’s Tavern to be exact.
The call for rain gardens came after marine biologist, Mike Kaill, found high levels of surfactants in the aquarium in the Spring Street Landing building. Surfactants like soaps, petroleum-based oils and heavy metals are commonly found in storm water. After a number of long-lived aquarium animals died, Kaill determined the cause of death to be the aquarium water, piped in from the harbor below.
The only study of the garden’s effectiveness was conducted by Kwiaht, a Lopez Island-based nonprofit environmental organization. The findings were grim.
Inadequate funding for proper study
In testing done the winter after the rain garden was installed, Kwiaht Director Russel Barsh found more copper in the water filtered by the garden than in unfiltered water tested the previous month. Barsh believes the garden’s soils and plants were to blame.
“It’s not surprising because in Washington state you can market compost as ‘rain garden’ even if a substantial portion is construction waste,” he said. “That means lumber treated with copper.”
Barsh said he offered to “fix” the garden for free and planned to recruit school-aged kids to help him dig up the garden and put in the “right” substrates and plants. County officials declined the offer, he said.
Krieger said that Kwiaht never contacted him about the offer.
He said funding for proper study of the garden’s effectiveness was limited from the start. Taking soil samples three to four times per year, pulling up plants to test and continuously testing the storm water would be necessary, and expensive.
“There wasn’t enough funding or follow up with any kind of real data,” Krieger said. “It was done too early in the life of the rain garden. It takes time for the soils to build the right levels of organisms for the rain garden to function properly.”
As far as Krieger is concerned, the money allocated for study of the rain garden would have been better spent making it as efficient as possible.
The effectiveness of rain gardens is not disputed in the scientific community, he said.
While the MRC proposed and followed through with the project, the rain garden is in the jurisdiction of the town and its care was to eventually become the town’s responsibility. The town and county are sorting through paperwork to make the transfer official.
In the meantime, Krieger and other volunteers clean out the garden’s sediment traps a couple of times per year, prune and replace dead plants, and pick up litter. Island Gardens changed out the soil about a year ago.
As the town prepares to take charge of maintaining the garden, it’s not at the forefront of curbing storm water pollution into the harbor, but it is on their radar.
Wilson said the town plans to do a controlled study by introducing an element into the water that runs through the garden to determine if the plants and soil are still functioning, but has yet to set a date for that test.
A better method?
Wilson said the town wants to identify a more efficient way of filtering storm water than having rain gardens on every street corner that require care and upkeep.
In a grant-funded project, the town is working with engineers to develop a “vault cartridge system” that could possibly be installed underground at the waterfront, where most of the town’s storm water drains. The vault cartridge, equipped with filters, is intended to capture 70-100 percent of the “first flush,” the surge of storm water that follows a heavy rain and carries surfactants that accumulate when streets are dry.
While still in its infancy, Wilson said a vault system would be more efficient than rain gardens because most of the storm water would drain to and be filtered in one place. From design, to construction, to maintenance, the project would have to be entirely funded by grants, he said.
Although the rain garden may not have sparked a mass movement along the streets of Friday Harbor, more and more are popping up around town.
The San Juan Community Home Trust has four in its Sunrise neighborhood, and plans to install a few more in phase two of the affordable housing project. The gardens are maintained by neighborhood volunteers.
Peace Island Medical Center installed rain gardens at its new facility as well.
“It’s an alternative to treating storm water and we’re at a turning point,” Krieger said. “It’s like incandescent light bulbs being replaced by LED light bulbs. Technically, rain gardens should be on most street corners—anywhere that water can flow and potentially get absorbed.”