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February 01, 2018

ERIN INSIGHT – Wastewater process requires trust

It would be incorrect to say that Erin’s urbanites will have no choices to make about the wastewater system that’s coming down the pipe.
Apart from three subdivisions that will be exempt from servicing, residents will probably be allowed to pay their share of the construction cost by cheque, or take out a loan from the Town of Erin at a very competitive interest rate.
The engineers we hired two years ago (for $883,770) were polite and professional while explaining the process to members of the Public Liaison Committee last week, but something did not feel right.
It would be too harsh to call it arrogance, but they projected an attitude of absolute certainty. They had done their tasks according to professional standards and traditions within their industry, so there were no crucial choices left to make.
The preferred options were to be self-evident in hundreds of pages of technical reports (downloadable at erin.ca), so their only duties were to offer brief explanations and listen to feedback – not to convince anybody of anything. Such a complex process requires a level of trust, and it can be difficult to achieve.
The best thing residents can do is make an effort to be informed. They can do that on Friday, Feb. 2, at a Public Information Centre, from 6 p.m. to 9 p.m. at Centre 2000, with a presentation at 7 p.m.
Our previous consultant B.M. Ross was telling us more than five years ago that we should build traditional gravity sewers, with some small pressurized sections in low-lying areas. The new consultant Ainley Group is telling us the same thing, in greater detail.
The residents and politicians of Erin may not be technically qualified to alter any aspects of a wastewater system, but that doesn’t mean they can’t try.
Transition Erin has pushed for a “small-bore” system, in which each property would have a new septic tank, discharging treated liquid to a system of small sewer pipes (4-8 inches in diameter). These would work mainly via gravity, with no pumps or grinders on people’s properties.
Such systems do exist, but both of our consultants have been against them, and there doesn’t appear to be much council support. Ainley’s task was to analyze the options.
Their report says the advantages of a small pipe system include less excavation, minimal water infiltration, no solids being transported, lower capital costs and low maintenance.
The list of disadvantages includes the large number of tanks on private property, pipes more subject to blockage, the need to pump out the tanks, corrosive effluent and the fact that these systems are not widely used in Canada, and not on this scale.
“Production of odour is common from improper house ventilation, manholes and system vents,” says the report. There would be extra costs for odour control at all pumping stations.
Transition Erin wants the small pipe option re-scored in the technical evaluation, based on their input, which could make it the preferred system. They also say Ainley has not projected a substantially smaller and less costly treatment plant needed for a small pipe system.
Council would have to order the new analysis, which could be costly. Though if it is valid, it should have been done in the first place.
Part of the frustration comes from false expectations about public input. Just because there is a “consultation” process doesn’t mean that public comments will change the details of what is planned. Even elected councillors have little influence on the plan.
Most infrastructure engineers work in a world of established standards, and comparisons with what has been done in other Ontario towns. Without a specific mandate from their customer to follow an innovative path, they will tend to opt for the low-risk, established process, even if it costs more.