Kingston saw 988.9 millimetres of precipitation last year, according to Canada Weather Stats.
Heavy rain in the city didn’t just cause multiple cases of flooding but also led to sewage overflows.
The amount of sewage overflow in Kingston used to be enormous, with over 700,000 cubic metres in 2003, as shown in the graph below. Utilities Kingston updated its sewage infrastructure and was able to control the overflow, bringing the amount down.
However, in the last few years, the number of sewage overflow incidents has been creeping back up.
“These bursts that we get — very heavy rain, very short period of time, very difficult for the system to respond to manage that kind of volume,” said Jim Miller, director of utilities, engineering and treatment at Utilities Kingston.
READ MORE: Extreme rainstorm floods downtown Kingston
When sewage water reaches a volume beyond what the system can handle, it overflows and spills into nearby bodies of water.
Last year, Utilities Kingston reported 26 separate overflow spills. That’s compared to 2017, when there were 20 spills, and 2016, when there were only 14 spills.
So, what’s causing this increase?
“It depends on the type of rain and, sometimes, the intensity and or the frequency of the rain,” said Miller.
Utilities Kingston is planning to take several measures to improve the amount of sewage overflow. The company has a four-year capital plan to help improve infrastructure that’s been approved by city council. Plans are also in place to reverse the water flow at the Portsmouth pumping station, which will redirect the overflow elsewhere, eliminating the spill.
“These improvements that we’re looking at doing to the system will address the amount of overflows, which will address the intensity of these storms,” said Miller.
Utilities Kingston plans to present last year’s findings in a report to council on Tuesday.