A McKenzie Interchange worker assesses the runoff entering the Colquitz River.

A McKenzie Interchange worker assesses the runoff entering the Colquitz River.

Heavy rains, broken drain threaten Colquitz fish

Unknown Environmental Hazard at the McKenzie interchange

Heavy rains, the unearthing of an unknown pipe, and construction at the McKenzie interchange project caused a large amount of unfiltered sediment to flow into the Colquitz River this week.

The sediment is a threat to the annual spawning run for Coho and other salmon in the Colquitz right now.

Dorothy Chambers toured the site with the Ministry of Transportation and Infrastructure and Jacob Bros. on Friday. She was supposed to tour the project, but instead the tour focused on the sediment runoff.

“It’s my understanding that one of the filtration pumps broke after a flood from the broken pipe,” Chambers said. “The sediment is a concern as the spawning salmon are in the Colquitz right this minute.”

The pipe, likely a storm drain, was broken during construction at the corner of the intersection closest to St. Joseph’s church and school. It was initially discharging clear water but since Wednesday it has been discharging sediment. The construction team, Jacob Bros., has placed several filtration systems to keep sediment from flowing into the Colquitz. However, it’s too much water and it is flowing directly down the hill to the river.

The sediment bloom of clay and dirt clouds the river and attaches to the gills of the fish and suffocates them, she added.

The Ministry of Transportation and Infrastructure released a statement saying “the project sediment and erosion control system was working as intended however, after a recent heavy rain, a large volume of sediment-filled water flowed into the site, overwhelming the project’s protection system.”

The source of the water is identified as coming from an old pipe which didn’t show up on any of Saanich’s maps. The pipe initially had clear water coming from it when it was unearthed by crews.

“Immediate steps were taken to capture this runoff water to ensure all water leaving the site is clear and not causing any environmental concerns.”

The area is still being closely monitored, while Saanich Engineering are attempting to find the source of the pipe, said Harley Machielse, director of Saanich Engineering.

“It appears to be a storm drain, and there’s already a storm drain that enters that area, which adds to the difficulties they’re facing,” Machielse said. “We’re collaborating and providing assistance as best we can to we’re working to identify the source of the pipe.”

The unidentified pipe could be anything, an abandoned municipal pipe or one that was previously on private property.

reporter@saanichnews.com