Hamilton estimates 337 million litres of sewage spilled

The city estimates that at least 800 million gallons of sewage from properties in East Hamilton washed undetected into the harbor for 26 years.

This calculation is based on the water meter usage of approximately 50 properties connected to a combined sewer pipe with a hole, creating a direct line to the lake.

The faulty connection – which city workers discovered in a sewer near Burlington and Wentworth streets last week – was corrected on Wednesday night.

“Hamilton Water staff completed the repairs as quickly as possible and repaired the sewer within 31 hours of discovery,” an update from the water department said.

The city said it had provided the Department for Environment, Conservation and Parks with the estimated volume of the leak of nearly a quarter of a century on Monday morning.

The city speculates that a contractor mistakenly made the hole in 1996 based on incorrect drawings. Staff were watching a video taken by management for an independent project in 2013 when something seemed wrong.

A water agency official “realized through experience that something ‘didn’t look right’ and initiated a field investigation,” according to an update due to be presented to City Council Monday afternoon.

The investigation confirmed an “improper connection” between the combined sewer and the storm sewer that emptied into the Port of Hamilton.

In their review, city water officials examined contract documents relating to a 1996 reconstruction and widening of Burlington Street East.

They revealed the roadwork included upgrades to underground pipes and a switch to an “mislabeled” combined sewer pipe, resulting in an “improper connection” with the storm pipe.

Additionally, staff found two videos – created for camera inspections in 2009 and 2013 – showing the maintenance access hole where the problematic connection was made.

The footage “clearly shows sewage draining into a ‘hole’ in the bottom of the pipe, but this type of connection between sewers is not uncommon in older towns like Hamilton,” the staff report said.

Because the videos did not indicate “immediate maintenance needs and structures in good condition,” they would not have been flagged by the contractor for further review.

As a result, “as of last Tuesday, staff do not believe that any city employee reviewed any of these videos.”

“Also, the contractor would not have had enough detailed knowledge of the city’s sewage system to identify the improperly connected sewer pipes.”

In 2015, the water department awarded a third contract for camera inspections, but the contractor couldn’t complete all of them on budget, so the shaky connection wasn’t investigated, Personal Update notes.

“Following this contract, Hamilton Water has decided not to issue another tender for this work.”

That was partly because the department had conducted two rounds of inspections as part of an annual sewer flushing program that addressed “many” maintenance issues. In addition, maintenance access holes showed “very little change in their structural integrity” during inspection cycles.

So far, the cost of containing the leak and correcting the channel configuration is about $30,000, the city says.

This included using vacuum trucks on site to prevent the sewage from flowing into the storm sewer before the pipes could be reconfigured.

The repair included installing a new 15-foot length of pipe to connect to the Woodward Avenue processing plant and capping both ends of the old pipe.

City officials “are in the process of completing a hydraulic analysis of the reconfigured sewers to confirm that the repairs undertaken are the most appropriate long-term solution.”

Last week, following the discovery, Environment Secretary David Piccini said he would direct the city to examine its entire sewage system and possibly create a “clean-up plan”.

On Monday, the city said it has yet to receive a formal order. A ministry spokesman was not immediately able to respond to The Spectator’s request for information.

But, ministerial order or not, the city says, “Hamilton Water is developing plans to study the sewage system so that all stakeholders can be assured that similar improper sewage connections do not exist elsewhere.”

The cost of a network-wide audit is unspecified. Existing city practice calls for proactive inspections of less than 2 percent of underground sewers per year — there are more than 1,268 kilometers of sewers and 573 kilometers of combined sewers.

Last week Mayor Andrea Horwath expressed hope that the province would help plan and fund the exam. “I think we have to be partners in this.”

In its report, after consultations with public health, water workers say: “It is very unlikely that any member of the public would have come into direct contact with the contaminated water.”

The Department’s Environmental Monitoring and Enforcement Unit has collected samples of the discharge entering the storm sewer and downstream from this site.

“Preliminary analysis results indicate that normal residential wastewater enters the storm sewer, and there is evidence that the wastewater was diluted when it reached the downstream sampling site.”

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