A pipe break leading to the Bonnybrook Wastewater Treatment Site on March 28, sent a significant amount of sewage into the Bow River—although the volume and cause remain under investigation.
Although the leak was considered significant by the City of Calgary, testing by Alberta Health Services has indicated that there is no risk to the public or to downstream users of the Bow River.
Mayor Jyoti Gondek, speaking about the break on Saturday, said that the city had immediately informed AHS and Alberta Environment and Protected Areas once the leak had been identified and addressed.
“I made the decision to hold this press conference today to provide you with the transparency and the accountability that you expect. Let me repeat, our drinking water is safe, risk to the public is low, and we contained this issue within three and a half hours,” the mayor said.
General Manager of Operational Services Doug Morgan said that staff at the Bonnybrook plant became aware of lowering levels of wastewater entering the facility starting last Monday on March 24.
He said that an investigation began into the causes of that decline of wastewater entering for treatment, and that the City of Calgary reached out to a number of regional partners that send their wastewater for treatment at the plant, and examined if the cause was a result of seasonal variations.
“When we started to see the trend this week, that’s when we started to broaden our approach and look for other issues in the community. Generally, when we have a wastewater break, it’s pretty apparent—311s come in quite quickly. So this was something different, and we’re just trying to nail down all of the variables as we work through the process,” Morgan said.
No lasting effects expected to human or environmental health of Bow River
Morgan said that physical examinations of the area where three wastewater pipes enter into the treatment plant did not show any signs of leakage until Friday morning, at which time City of Calgary crews were able to stop the leak and prevent any further sewage discharge.
“By 2:30 p.m., we had identified which pipe was the issue, closed the valve to that pipe and rerouted the wastewater to the two other functioning pipes so that service could continue normally. We continue to monitor closely and investigate the root cause of the leak and the E. coli levels in the river water,” he said.
“Our immediate focus is continuing monitoring and ensuring the release is fully stopped. The city is currently conducting a full assessment to determine the last inspection date for these pipes, and is reviewing a long-term maintenance and monitoring strategies to prevent similar issues.”
He said that wastewater levels entering the plant had returned to normal, and that no restrictions or boil water advisories had been issued for users of the Bow River.
Mayor Gondek took some issue with City of Calgary administration for the length of time that it took for them to inform her of the sewage discharge.
She said that she was able to receive a briefing by administration on the leak after 8 p.m. on Friday, and that led to the decision to hold a weekend press conference.
“To not have found out about this until yesterday evening, is incredibly disappointing to me,” the mayor said.
“I continue to ask questions of administration about how they will make this better next time, and why it was this time that I didn’t get the information in a more timely manner.”
