About $600,000 spent since 2012 to reduce inflow and infiltration into Palmerston’s sewage system has been a good investment, says the Minto’s public works director.
The town has been struggling with infiltration problems with Palmerston’s aging sewage system for more than a decade.
Since 2004, the town has conducted numerous dye and smoke testing programs attempting to find the source of the problem, initially focusing on suspected inflow from residences and other buildings in town with sump pumps and other drainage systems connected directly to the storm or sanitary sewer systems.
However, in 2012, the municipality began to focus on leaky manholes as a key source of inflow and infiltration and began to make progress.
With existing capacity allowing for only 42 infill and 88 new development lots at the time, council passed a bylaw in April 2011 limiting development in Palmerston.
The bylaw required a resolution of council to allocate any of the town’s limited sewage capacity to development.
That situation improved to the point that by October of 2013 the bylaw was altered to allow capacity to be allocated “as directed by the chief building official in consultation with the public works director.”
At the Oct. 21 council meeting, public works director Brian Hansen reported that nearly all the unauthorized hookups have been eliminated.
“The 2014 calculations are not complete, but staff noticed a considerable reduction in flows when a major cross connection from the Norwell Secondary School roof and courtyard was disconnected,” states a staff report from Hansen and chief building official Terry Kuipers.
They noted that additional locations where leaks were causing problems were discovered during the process of water meter installation.
“Staff is confident that even with heavy rains this year a further reduction in flow will be achieved.”
The report notes there is still work to be done to decrease inflow and infiltration including replacement of mains and lateral connections below the water table, and suggests, “The town should consider a program to encourage landowners to disconnect sump pumps, weeping tiles and similar cross connections into the sanitary system.”
In the past year, Palmerston has seen an increase in both residential and non-residential development, with five residential units being constructed and the equivalent of 19 unreserved residential units for non-residential development.
Three unreserved units and one reserved unit have also been released, due to the demolition of the former Palmerston OPP station, and a residential fire for which the house has not been reconstructed, leaving the treatment plant’s capacity at 59 reserved units and 168 unreserved units, for a total of 227 units – 10 less than at this time last year.
The report estimates the town has enough capacity to accommodate about 10 years of normal growth.
Hansen noted the town has just begun to “put a dent” into a similar program in Harriston.
“There’s quite a bit left in Harriston to do,” he noted.
“It sounds like there’s going to be that much again,” said councillor Ron Faulkner, referring to the $610,000 spend on the Palmerston system.
“At least,” replied Hansen.
Hansen stressed the town needs to continue “educating the people about getting their sump pumps off the system and (removing) rain leaders going into it, because you’re treating water that doesn’t need to be treated, and that’s quite a process.
“We took 671 cubic metres a day just off that high school, on an average. That’s a lot of water that we were treating that didn’t have to be treated,” Hansen pointed out.
CAO Bill White said he anticipates the end result will be increased capacity in Palmerston.
“We want to reserve judgment until we see our three-year rolling average on it, but I’m optimistic that within a year or so we’ll be adjusting our sewage allocation units to above 227,” White said.
“That doesn’t meant the job is done, but we’ve made a lot of strides.”
Deputy mayor Terry Fisk asked if town was getting “good value” for the money spent on the inflow and infiltration prevention work.
“I think it’s really good,” said Hansen.
