Chlorine exposure results in the loss of 2000 Coho fry
Shortly after 11:30 a.m. on Thursday, September 24, a resident alerted the Hoy/Scott Watershed Society that dead fish had been spotted in Hoy Creek. The resident had also reported the incident to the City of Coquitlam.
Hatchery volunteers responded quickly, along with the City’s environmental team, who began testing the water both in the creek and at the hatchery, where over 4,000 Coho fry were being housed.
A faint smell of chlorine was noticeable in the area, and a source of the pollutant was identified nearby. Unfortunately, the damage had already been done. Dead fish could be seen along a one kilometre stretch of the creek.
A devastating loss
Initially, only one or two dead fish were observed in the hatchery. Within an hour, however, it became clear that chlorine had entered the holding tank and that the fish had been seriously affected. Hatchery volunteers acted quickly to mitigate further loss by shutting off pumps which intake water from the stream. The City assisted with testing the creek and water in the holding tank until results improved and then water was reintroduced to the holding tank.
The next morning volunteers were pleased to see survivors in the hatchery tub! Official counts are not in yet, but approximately half of the fish survived.
The loss is heartbreaking for the Society and our volunteers. Raising young salmon requires considerable time, care and commitment, and these fish represented an important part of the hatchery's salmon enhancement work.
We are grateful to the resident who noticed the dead fish and reported the incident. That quick action allowed City staff and hatchery volunteers to respond as quickly as possible.
Only rain down the drain
This incident is also an important reminder about the connection between storm drains and our local waterways.
Only rain should go down a storm drain on residential or commercial property.
Storm drains can lead directly to local creeks and streams. Pollutants entering the drainage system can harm or kill fish and other aquatic life. Chlorine and pool chemicals, in particular, can be lethal to fish.
What goes down a storm drain can ultimately make its way into the very waterways we are working to protect.
What Happened?
City of Coquitlam advised that an industrial strength chlorine from a pressure washing job nearby went down a storm drain that fed directly into the creek. Further investigation will determine fines and mitigation measures.
Continuing our work
Despite this difficult incident, our regular volunteer work will continue as planned. Our volunteers remain committed to protecting Hoy Creek, supporting the hatchery and doing what we can to improve the health of the watershed.
Thank you to the City of Coquitlam's environmental team, DFO and our dedicated hatchery volunteers for their quick response and ongoing efforts.
Together, we can help protect Hoy Creek and the fish and wildlife that depend on it.