By Stew Slater
Flow meters were installed inside Town of St. Marys wastewater pipes last week as part of an effort to discover and hopefully eliminate sources of exterior inflow and infiltration into the system.
Next up will be a public education campaign to make residents aware of possible in-home solutions to prevent the problem — mainly the correction of improperly-installed sump pumps. And, depending on how aggressively town councillors want to pursue the solutions, after that could come the approval for town staff to enter homes and conduct inspections.
“Really, we just want people to understand why we’re doing this, and why it’s important to get this work done, and here’s some help if you need it,” commented Councillor Don Van Galen, when Senior Manager of Technology Jed Kelly delivered an update about the Inflow and Infiltration Strategy to a Committee of the Whole meeting on Tuesday, March 5.
Inflow and infiltration have been blamed for adding to the load of the wastewater treatment plant, thereby causing the town to consider expansions ahead of its original plan. That’s because water that should be directed into the stormwater management system instead ends up in sewers.
Kelly’s report to the March 5 meeting included background information about previous monitoring of the problem undertaken by the town. “In circa 2003, Conestoga Rovers and Associates, at the request of the Town of St. Marys, completed sanitary flow monitoring at various locations within the system,” the report explains.
A small number of locations were identified by Conestoga Rovers at the time at which higher-than-expected infiltration was occurring. These included “the area draining north towards the Huron Street and Elizabeth Street intersection” and “upstream of the Park Street and Water Street collection point (to the east).”
At that time, nine distinct zones were identified in the town’s sanitary sewer system at which exterior influences should be monitored. With this new Inflow and Infiltration Strategy, those zones have been maintained.
And last week, staff installed flow meters in each of those zones, in an effort to update the Conestoga Rovers findings.
Kelly explained this year’s snowpack is beneficial, especially compared to the scarcity of the white stuff a year ago. It means when a thaw comes, there will be considerable snowmelt and problem areas may be more easy to identify.
“We set a March 1 timeline to get (the meters) in place because we wanted to make sure they were in place before the snow melted,” he told councillors. “Hopefully, now, they’ll be there to catch a big thaw.”
In an interview after the meeting, Kelly added that the data provided by the flow meters will be most important during the early morning hours, between 1-4 p.m.
“That’s when water usage is typically really low,” he explained. “So, if you’ve got increased flow in the sanitary sewers at that time, you pretty much know there has been some infiltration.”
Also part of the Inflow and Infiltration Strategy are a series of utility hole inspections, as well as groundwater and precipitation monitoring programs. But the public, most likely, will be most interested in plans for public education and, possibly, inspection and enforcement.
“Given that public cooperation is vital to the success of any inflow and infiltration program,” the report to councillors explained, “a suitable public education plan and accompanying materials” will be developed “that clearly outline the goals of the study and the responsibilities and requirements for individual home or property owners relating to stormwater and sanitary management.”
If approval is granted to move forward with the strategy, Town staff will also “assess the usefulness of possible subsidies to encourage homeowners to change known inflow/infiltration issues at their properties.” And there will also be an assessment of “ the usefulness of a detailed inspection program.”
Van Galen pressed Kelly and CAO Kevin McLlwain to provide details about the public awareness campaign, noting that it’s the preferable route compared to sorting through the legalities of any actions involving inspection and enforcement. The veteran councillor also stressed the importance of providing some sort of assistance — either technical, financial, or both — to help residents fulfill the request for proper sump pump installation.
McLlwain responded: “You’re absolutely right.” But the CAO also predicted that some property owners will be resistant to requests to upgrade or fix their sump pump outlets, even if there’s an awareness campaign. With others, meanwhile, a series of public education messages will prove both important and effective.
And McLlwain agreed the Town also bears some responsibility, and that’s why the other measures like utility hole inspections are part of the plan.
“Because there isn’t just one solution here. There’s a range of solutions that we will have to move forward on.”
Nine zones of study established
The following are described in the new Inflow and Infiltration Strategy for the Town of St. Marys, released to Town Council on Tuesday, March 5, as “the preferred primary locations for flow monitoring devices to be installed” within the sanitary sewer system.
Area 1: Water Street North and Jardine Street, recording flow moving south from Emily Street.
Area 2: Parkview Drive, recording flow from Station Street and Wellington Street.
Area 3: Elgin Street West at trunk main to Wastewater Treatment Plant.
Area 4: Thomas Street between Westover Street and Park Lane.
Area 5: Elgin Street and Brock Street, recording flows moving west on Elgin Street.
Area 6: James Street South at the intersection of Southvale Road, recording flows from Meadowridge Subdivision.
Area 7: James Street South, south of the intersection of South Service Road, recording flows moving north on James Street South.
Area 8: Water Street South between the Gore Street and Front Street road allowances (opposite the Canadian Baseball Hall of Fame entrance), recording flows moving north on Water Street South.
Area 9: Queen Street East between Water Street and Wellington Street.