Voices of Water: Lou di Gironimo
As General Manager of Toronto Water, Lou Di Gironimo overseas the vast array of infrastructure and staff that supplies drinking water to 3.2 million residents and deals with the wastewater of 2.6 million residents. Like a set of bellows, the city draws its water from Lake Ontario, and then expunges its treated wastewater back into the lake (the lacework of sewers that underlay the city add up to 6,200 miles in length). But when the rain pelts down extra hard, the city’s sewage and stormwater exceeds the carrying capacity of its treatment plants. As a result, excess combined sewage and stormwater – to the tune of 9 million cubic liters of combined sewage a year – is discharged straight into the lake.
I interviewed Di Gironimo from the roof of the heat recovery building at Toronto’s Ashbridge Plant, Canada’s largest wastewater treatment facility. In the same gaze, one could see Toronto’s skyline slope down to meet Lake Ontario, which shimmered blue in the sun and wind.
What’s the key thing that Torontonians need to understand about their water?
One thing we try to tell residents is that they’re connected to the lake. It’s either through their sewage pipe that ends up coming to a sewage treatment plant where we discharge back to the lake or if there’s a storm pipe on their property the rainfall that hits their roof or driveway goes into a catch basin on the road, it’ll end up in a local creek or river and make its way to Lake Ontario.
So they are directly connected to the lake no matter where they live.
So what is in stormwater?
People think stormwater is pristine. Well, it is when it comes out of the clouds but not when it hits an urban surface the size of Toronto. That stormwater gets polluted as well.
It’s motor oils; it’s glycols from antifreeze; it’s dust and debris; it’s cigarette butts; it’s birds, it’s dogs. You name it, we all pollute the environment in one way or another and the rainwater picks it up, mixes it all together, puts it in a pipe and we’re having to deal with it somewhere.
A lot of the creeks that used to run along the surface of this land before it became an urban environment now run underground and have become part of the sewage system. Do you see any value in bringing them back to the surface?
Well, we do that where we can.
If we go back 100 years what we had were old creeks that were really sewers. We polluted them and they smelled and they had cholera issues and disease so the forefathers of our city at the time said we’d better cover these over.
So some of those underground rivers are now sewers that we use today. To try to return them would be rather difficult. You’re trying to unbake the cake. It would be really nice to see that happen.
Toronto Water has inherited many problems from history and this city’s previous leaders. What do you hope to pass along to your successor?
I want somebody to remember and thank us for doing the right things 50 years from now. We’re building a city for the future and it’s going to be here for hundreds of years.
So what is your vision of that city for the future?
I see a city that understands that water is really the most precious resource we have.
What we would have is a city that manages water as rainfall, and we deal with it at source on our properties. And we treat stormwater in ponds so we can discharge it clean to the environment. Our sewage treatment systems are functioning to their peak capabilities so we’re treating it as best we can and returning that to the environment. And slowly what we’ll see is a cleaner Lake Ontario. So therefore it makes it easier for us to live by the lake, swim in it, play in it, fish in it and enjoy it.