Mushrooms used to clean up urban streams

CORVALLIS, Ore. (AP) — An environmental group is attempting to clean the waters in Corvallis’ Sequoia Creek — and potentially the Willamette River beyond it — using an unusual tool: mushrooms.

The process used by volunteers with the Ocean Blue Project, an ecological restoration nonprofit, is to place mushroom spawn and a mixture of coffee grounds and straw in burlap bags that mushrooms can grow in, and then place the bags so that water entering storm drains will filter through them. The technique is attempting to take advantage of the natural ability of mycelium — the underground part of fungi — to break down toxins like oil and pesticides and metabolize harmful bacteria like E. coli.

Ocean Blue Project volunteers placed their first test bag, containing yellow oyster mushroom spawn, in a drainage chute near the Ninth Street Coffee Culture on Sunday.

Richard Arterbury, president of the Ocean Blue Project, said he thinks the project has huge potential.

“If you put enough of these bags by the Willamette River it could potentially change the river,” he said.

Oregon Department of Environmental Quality water sampling from 2008 to 2012 showed the presence of pesticides, flame retardants, metals, and chemical ingredients from consumer products in the river. The Oregon Health Authority also has an active mercury advisory warning that children should not eat more than one serving of resident species of fish from the main fork of the Willamette River a month, and that adults should not eat more than four servings.

The Washington Environmental Council has been using similar techniques in parts of the Puget Sound region, and a unrelated study from the state has shown fungi helped remove fecal coliform bacteria from flowing water.

According to Arterbury, the technique could potentially be a low-cost way to use biologic processes to reduce pollution in waterways. Coffee Culture donated burlap bags that carried coffee beans along with the used coffee grounds — all of which otherwise would have been thrown away. Arterbury said other food waste — possibly grain waste from local breweries — could be used to grow mushrooms.

Since the technique is relatively new, Arterbury said Ocean Blue will test water samples in the creek to see how the placement of the bags affects water quality. He said the tests will check for the presence of E. coli, phosphorus, and nitrates, and measuring pH and oxygen levels.

Arterbury said the project has received positive support from the city of Corvallis. He said the biggest concern he’s heard is that people may eat mushrooms that have absorbed dangerous chemicals and heavy metals. Arterbury said since the mushrooms are grown in sacks they are not visible, but he will also hang signs warning people not to eat the mushrooms from the bags.

To Arterbury, using fungi for storm water filtration is a part of a larger process of restoring the creek. In addition to placing the first bag, he organized a cleanup Saturday during which about 20 volunteers cleaned trash from in and around the creek. He also wants to remove invasive blackberries from the creek banks to encourage growth of native plants that can better shade the water to improve stream health.

Rosalie Bienek, a biology instructor at Linn-Benton Community College and a board member at the Ocean Blue Project, brought the idea of using fungi as filters to Arterbury. She said she learned of the technique a year ago from a book called “Mycelium Running,” by Paul Stamets, who has also done a TED Talk on the subject.

“It’s got a lot of potential, and few people in the area are studying it,” said Bienek, whose research concentration is on botany and using native plants in restoration.

Bienek and Arterbury plan to place more of the bags along the creek, and if the water testing shows positive results they want to expand the use of mycofiltration to other areas along the Willamette River.

“If this has a great result we’re taking it everywhere,” said Arterbury.