24 Olympic-sized pools of sewage leaked into Hamilton Harbour from Rutherford Ave. leak
Published January 13, 2023 at 4:08 pm
The City of Hamilton has estimated that around 59 million litres of sanitary sewage discharged into the Hamilton Harbour over the 26-year span before an incorrect connection was found, and fixed over the past week.
That works out to the equivalent of about 24 Olympic-sized swimming pools. It is just over one-sixth of the size of the Burlington St. spill (337 million litres) that was discovered last fall. That finding prompted Hamilton Water to launch a “risk-based inspection pilot program” to look for other instances of where sewage from homes and businesses might have been flowing into storm sewers and out into the harbour — rather than to a wastewater treatment plant.
Like the Burlington St. spill, Hamilton Water believes the installers of a new storm sewer made a mistake in the mid-1990s.
“City staff believe that the incorrect connection was made in 1996 when a new storm sewer was installed on Myrtle Avenue,” a release from the city on Friday stated.
Following disclosure of the Burlington St. leak in November, Mayor Andrea Horwath said she would order an audit of Hamilton’s sewer system. Ontario Environment Minister David Piccini also spoke publicly of issuing an order to the city.
For the time being, the city says no order has been issued by the Ministry of Environment, Conservation and Parks (MECP). The pilot project is just past the midpoint of inspecting 292 maintenance holes in older areas of Hamilton, specifically the combined sewers in the areas where there are overflows to the Wentworth St., Birch/Sherman, Ottawa and Kenilworth combined sewer overflow outfalls.
One hundred and fifty-one inspections have been completed. Six undocumented sewer regulators (locations where combined sewage may discharge to the storm sewer during wet weather), and one cross-connected sewer (the one identified at Rutherford/Myrtle) have been found. The latter was repaired at 3:40 p.m. on Wednesday (Jan. 11).
“As mayor, I am deeply concerned any time we find a sewer leak going into Hamilton Harbour,” Horwath stated in the city’s communication on Friday. “Learning from the discovery of November’s leak, we are proactively looking for these misconnections in our aging sewer system, and we will continue this work going forward.”
The estimate of the spill’s size is drawn from water meter usage data from the 11 properties connected to the combined sewer pipe.
“This methodology was identified as the most accurate representation of the discharge over the time period,” the city stated on Friday.
Numbers and methodology
- The estimated cost of the repair work (excluding staff time): The city says the tally is $37,529. That includes initial CCTV investigation and flushing ($1,512), vacuuming ($10,017), excavation, parts and sewer realignment (22,000), and permanent road restoration ($4,000).
- How inspections are conducted: Municipal workers are visually inspecting each maintenance hole and are also using a pole-mounted camera. They specifically look for connections in each chamber that are undocumented. These connections are then further inspected using a camera that runs through the pipe and other means, such as dye tests.
- Whether the province will issue a remediation order, à la Chedoke Creek (#Sewergate): The city says it remains in “close communication” with the MECP Spills Actions Centre and shared the estimated volume of discharge with them on Friday morning. It adds, “Conversations have been productive, however, at the time of this news release, an order has not been issued,” by the province.