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Q&A with Lake Ontario Waterkeeper

Mark Mattson President of Lake Ontario Waterkeeper
Lake Ontario Waterkeeper
Mark Mattson President of Lake Ontario Waterkeeper

Mark Mattson, the president of Lake Ontario Waterkeeper and Swim Drink Fish Canada, has advice for keeping waters clean and safe.

Mark Mattson President of Lake Ontario Waterkeeper
Credit Lake Ontario Waterkeeper
Mark Mattson President of Lake Ontario Waterkeeper

Lake Ontario Waterkeeper recently completed a report outlining the water quality and conditions in Toronto’s harbor. What were some of the findings?

Mattson: Our investigation team collected 166 water samples from the harbor.

Most of the sewage pollution they found was near the water’s edge.

When we were testing, the water sometimes looked clean, but bacteria levels still soared. These results show why water testing is important. It is really the only way for anyone to know when the water is clean.

Of the 166 single samples that were taken, 57 of them contained more E. coli bacteria than is recommended for safe boating by Health Canada’s Guidelines for Recreational Water Quality.

A further 51 individual samples contained more E. coli bacteria than is recommended for swimming.

That’s [about two-thirds] of samples that failed to meet Canadian water quality standards. For a single sample to be considered a fail for boaters, the test result must exceed 2000 E. coli/100 ml. Anything more than 100 is a threat for swimmers and aquatic life.

The single highest sample we got came from Bathurst Quay on September 27: 170,000. That’s 170,000 E. coli bacteria colonies, a number that far exceeds any measure of safe water quality. Out of 40 samples taken from Bathurst Quay, only six were below 100.

Waters tested in Outer Harbour and at the Islands tended to have much better results, and more passes on average.

When you look at all the results as a whole, it suggests what we’ve suspected all along: The worst sewage can be found near sewage and stormwater outfalls and the mouth of the Don River.

Now that the harbor report is completed, what issues will Waterkeeper tackle next?

Mattson: The publishing of our report is a step forward in to reclaiming our harbor.

There is more work to be done: We are working toward increased sampling in the harbor. We want to produce regular sample results and publish them weekly in our Swim Guide [app] for harbor users.

Additional Notes:

We have world-class fishing here, great paddling waters, and a robust sailing scene. Fishing, canoeing, kayaking, sailing, dragon boat racing … there are a number of ways people use the Toronto harbor for recreation. ...

We test the water to gauge the threat level to our health. Quite simply, the more sewage in the water we paddle, fish, and swim in, the greater chance we have of getting sick.

Combined sewer overflows have also has plagued your community. What are some of the key things residents can do to help cut down on trash found in sewer overflows?


Residents need to ensure their City of Toronto officials makes swimmable water in Toronto a priority across the waterfront, bays and rivers.

Residents of Toronto need to do everything within their power to reduce contaminated stormwater -- disconnect rain spouts, don’t wash cars in driveway, replace hard surfaces with natural landscapes, inspect sewage connections in homes, take hazardous chemicals and paints to proper waste sites.       

There is good news. Water quality is like weather, it changes every day and most days, pollution’s grip on Toronto harbor is pretty weak. The further you go from the harborfront, away from the outfall locations, the cleaner the harbor water. On most days, bacteria doesn’t even reach the middle of the harbor. Basically, if we can turn off the pollution taps, Lake Ontario will rebound. 

If we stop the sewage flows, we can have a swimmable Lake Ontario in Toronto. We’ve done it before.              

In the 1990s, Most beaches in Toronto failed water quality tests. Today, you can swim without worry at most city beaches. That’s what hard work and infrastructure investment can do.

That’s what happens when people decide it’s time to win back Lake Ontario. Every success story starts with people deciding they want clean water.        

Copyright 2016 Great Lakes Today

Angelica A. Morrison
Angelica A. Morrison is a multimedia journalist with over a decade of experience in the field.
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