Years of expensive attempts at stemming the flow of surface water into sanitary sewers having proven underwhelming, Woolwich will be opting for lower-cost options in future rehabilitation projects.
Known as inflow and infiltration (I&I) projects, the work has been ongoing in Elmira since 1994 and in St. Jacobs since 1999.
With new data, the township has determined large-scale I&I work is no longer cost-effective, director of engineering and planning Dan Kennaley told councillors meeting Tuesday night. Instead, small improvements will be undertaken. That includes manhole repairs, identifying leaking laterals from homes and investigating a sump pump program. In the latter case, the township would look at installing the pumps at homes where foundation drains are disconnected from the sanitary sewer system.
Woolwich is now convinced that problems with peak flows that overwhelmed wastewater treatment plants in Elmira and St. Jacobs had more to do with inadequacies at the plants than with I&I problems, he said.
On this point, the township is in disagreement with Waterloo Region, which operates the plants and which has paid half the cost of I&I work in the township to date.
The Ministry of the Environment reports that bypasses of raw and partially treated sewage occurred 11 times in Elmira and five in St. Jacobs between 2002 and 2008. It directed the municipalities to fix the problem; additional storage at the treatment plant should alleviate the problem.
Kennaley’s report called for an end to the so-called third pipe option, a technique used in major I&I reconstruction projects – especially in Elmira’s Birdland subdivision – whereby another pipe is installed far deeper than water and sewer lines, diverting excess water.
The cost savings are dramatic. In the next Birdland reconstruction project, simply replacing the watermain and resurfacing the road in the area around Nightingale Crescent will cost $2 million. With the third pipe, the bill would swell to $10 million, he explained.
“It’s not providing the level of benefits to justify continuing the project.”
Coun. Ruby Weber called Kennaley’s report “troubling,” noting the township has spent millions of dollars that may not have been cost effective. That said, she noted that the work was undertaken when lack of sewage capacity prevented new homes from being built.
“We were told we’d have to get into this program to have sewage capacity for Elmira to grow.
“I’m not happy with any of this,” she added, saying there’s no reason to continue with major I&I work.
Coun. Mark Bauman, however, pushed for solutions such as the sump pump program.
“Maybe we haven’t got the best bang for our buck,” he said of the past I&I work, but noted the township has to strike a balance between what’s right environmentally and being fiscally responsible.
