Bell Slough residents remove invasive irises to protect waterway in Chilliwack, study to begin

Residents living along Bell Slough and other volunteers gathered on Thursday to remove invasive plants that have been choking the waterway in Chilliwack for years.

The invasive plant is the yellow flag iris which has grown so thick it’s preventing native species and water from moving through the slough.

It’s the second time the group of about 25 people have climbed into kayaks and put on hip waders in order to snip the iris seed pods before they drop into the water. The first seed pod removal was in the summer of 2021.

READ MORE: Residents snip seed pods from invasive irises to help save slough in Chilliwack

The rhizomes of the yellow flag irises have grown deep in the water preventing fish and other animal from being able to swim through the slough. Rhizomes are subterranean plant stems that send out roots and shoots from its nodes.

Once it gets into a waterway, the rhizomes build a shelf and it can close in an entire waterway, explained Roxanna Froese with Watershed Watch Salmon Society.

Although the ideal solution is to remove the irises completely, it’s much too big of a task for the group of volunteers.

The Watershed Watch Salmon Society, along with the residents, led the iris removal event on July 14. Volunteers with Fraser Valley Invasive Species Society also joined them.

The seed pod removal was initiated in 2021 by many neighbours who live along the Bell Slough which runs from the north end of McDonald Road – where it connects with the Fraser River – to around the 11300-block of McSween Road.

Froese said the condition of the slough is slightly worse than last year.

“The city has no mandate to protect this waterway because there’s no native (animal) species left in it. But, the reason why there’s no native species left in it, is because there’s so much issue with all of the overgrowth and the weeds and the invasives,” Froese said. “It just seems like a backwards way of looking at this.”

But because of the community involvement in removing the iris seed pods and restoring the slough, in January the City of Chilliwack approved $60,000 for a feasibility study.

“Without community interests, council won’t allocate funding,” said Kris Biela, engineering technologist with the city.

He said that funding comes as a direct result of the work the ‘Friends of Bell Slough’ have done.

Starting early August, a consultant team from Stantec – made up of biologists and engineers – will begin their study on Bell Slough. The team’s research is expected to be complete by the end of 2022.

Another community project took place in October 2021 where folks gathered to plant trees along the Bell Slough.

READ MORE: Bell Slough residents, Islamic Relief Canada come together to plant trees along slough in Chilliwack

“Events like this are splendid to bring that riparian space back which brings the water quality back, which brings our critters back into our space,” said Steve Clegg, environmental services specialist with the city, during the event on Oct. 16, 2021.

“All of this work that’s being done by volunteers is to show the city that people care about the waterway and that it is an asset that’s worth protecting and restoring,” Froese said.

A big focus is getting more water flowing through Bell Slough by improving connections with upstream Camp Slough and Nelson Slough and improving the connection in the Fraser River.

“One thing we need is fresh water coming into the slough. There’s a direct correlation between water quality and aquatic habitat, and of course ecological performance of the slough,” Biela said.

He added the goal is to introduce “more fresh water so that the local wildlife can really thrive in the slough again.”