City still sucking sewage in Chedoke Creek
30 truckloads so far in cleanup from overflow-tank leak
The city has vacuumed 30 truckloads of sewage-laced water out of Chedoke Creek as part of an ongoing cleanup of leaked human waste from an overflow tank.
But more permanent changes are coming to the area’s aging sewer systems as the city battles a stubborn bacterial pollution problem in the west-end waterway.
The sewage leak was discovered last week after residents complained about a strong odour and floating debris at the creek’s outlet into popular paddling destination and nature sanctuary Cootes Paradise.
Water tests showed spiking E. coli bacteria counts in and around the creek mouth, prompting public health officials to warn residents to stay away from the water. The Royal Botanical Gardens even yanked a dock out of the water at Cootes Paradise for the first time since it was installed a decade ago to discourage determined paddlers.
Vacuum trucks will continue the cleanup through most of this week after heavy rains on the weekend “flushed out” leftover debris into the makeshift arms of floating pollution barriers set up by the city in the channelized creek, said wastewater operations director Nick Winters.
He said teams of workers — some in boats, others in hipwaders and wielding leaf-blowers — help corral and direct the floating pollution to allow vacuum trucks to suck out the watery waste. So far, 30 truckloads — or about 220,000 litres — have been released back into sanitary sewers leading to the Woodward Avenue treatment plant.
The cleanup is already helping with the odour, but the RBG won’t give eager paddlers the go-ahead to put in at Princess Point until tests show the water is safe, said head of natural lands Tys Theijsmeijer.
“We’re not there yet. It (the sewage) is still noticeable,” said Theijsmeijer. “It’s a safety issue now and probably an algae issue for the rest of the summer, at least.”
Winters said a city investigation revealed the sewage leaked out of a “bypass gate” that cracked open on one of the city’s largest sewage overflow tanks. The building-sized holding tank is buried under Cathedral Park and is capable of trapping up to 77,000 square metres of watery sewage that would otherwise overwhelm the sewer system in a storm.
That leak caused the most recent and infamously stinky problem. But even before the leak, annual sampling programs have “painted a concerning picture” of stubborn pollution levels in the creek leading to Cootes for several years, Winters said.
That’s why the city has been painstakingly tracking and replacing rogue residential sewer hookups in the area for years — about 180 so far.
New investigations and projects are in the works, too.
That includes a video investigation of old, combined storm and sanitary sewer pipes in the area. Such probes recently revealed two “previously unknown” combined sewer overflow outlets to Chedoke Creek that could pollute the waterway during storms.
The city also hopes to add new “control gates” in strategic sewers in the next few years that will allow high-tech redirection of storm flows away from problem areas along the Chedoke Creek.
And if the Frid Street extension goes ahead as part of a planned but contentious light rail transit project, a proposed trunk sewer would also help deal with a stubborn sewer overflow near Aberdeen Avenue that spit sewage into the creek 42 times last year.