Mark Mattson

Mark Mattson on Swimming in Urban Areas Swim Drink Fish President discusses the importance of urban swimming areas and the legacy of the Gord Edgar Downie Pier in Kingston, Ontario.

open.substack.com/pub/swimdrin...

From sewage and scum to swimming in ‘blue gold’: how Switzerland transformed its rivers In the 1960s, the Swiss had some of the dirtiest water in Europe. Now, their cities boast pristine rivers and lakes – and other countries are looking to follow their lead

The Swiss did it so can Canada www.theguardian.com/environment/...

Basic Fish Consumption Survey

We need help survey123.arcgis.com/share/9fe189...

Would You Jump Into Your Local River? Swimmable Cities May Be Within Reach as Once-Polluted Waterways Are Restored Efforts to improve the “swimmability” of urban areas are gaining global traction, from Paris to Chicago

Awesome article www.smithsonianmag.com/science-natu... @swimdrinkfish @LOWaterkeeper

Sewage Is Canada’s Quiet Crisis: It’s Time to Finish the Job Canadians want to believe we are a "water nation." We point to the Great Lakes, the St.

Canadians love to call ourselves a "water nation," but there’s a dirty secret flowing into our waters. In 2026, raw sewage is still our quiet crisis. After 20 years of work at @SwimDrinkFish, I’m looking at why we still haven't "finished the job." open.substack.com/pub/waterkee...

With heavy rains comes sewer bypasses & combined sewer overflows into Lake. Toronto reports sewage bypasses but not sewage overflows. Bypassed sewage is screened & disinfectant added but not “treated”. Wish @311 was clearer about that. We need to do better all around.

With all the rain forecast for Toronto & other Lake Ontario cities, beware of flooding in rivers & creeks. Also sadly, sewer overflows. Always a huge problem in spring — not good for fish habitat or human recreation. Nor for our drinking water. @swimdrinkfish @LOWaterkeeper

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Honoring the Guardians of Our Water: An International Women’s Day Tribute On International Women’s Day, conversations often focus on leadership tables, boardrooms, and barriers still to be broken.

Honoring the Guardians of Our Water: An International Women’s Day Reflection open.substack.com/pub/waterkee... @swimdrinkfish @wkalliance.bsky.social

Waterkeepers would not be Waterkeepers without one another. Yesterday, I received a message from a fellow Waterkeeper.

Waterkeepers would not be Waterkeepers but for other Waterkeepers. open.substack.com/pub/waterkee... @swimdrinkfish @LOWaterkeeper @Waterkeeper

Map - Biinaagami

One of the great accomplishments in last few years is the creation of the Great Lakes St Lawrence River digital map in the Biinaagami project www.biinaagami.org/map @cangeo @swimdrinkfish

Beyond the Dinosaurs: How Distributed Energy Quietly Changed Canada’s Power System In the summer of 2026, a strange thing is now possible in Ontario: You can lock your door, leave for two months, and come home not just without an electricity bill, but with a credit.

Lots of questions about options in Ontario for a modern energy plan that protects the province and protects the environment. Here is a take beyond the nuclear vs fossil fuel debates open.substack.com/pub/waterkee...

Beyond the Dinosaurs: How Distributed Energy Quietly Changed Canada’s Power System In the summer of 2026, a strange thing is now possible in Ontario: You can lock your door, leave for two months, and come home not just without an electricity bill, but with a credit.

open.substack.com/pub/waterkee...

Before we commit to more nuclear expansion on Lake Ontario — let’s explore the need, alternatives, costs and risks of all options. Ontario is smarter than allowing power, politics & influence dictate our future. open.substack.com/pub/waterkee...

Gord Downie and The Sadies 'Louisianna' Gord Downie plays Lake Ontario Waterkeeper a special tune.

Love the Gord Downie Sadie’s new album. Awesome. Recall many of those live shows fondly. Around 2008, Gord & the Sadie’s recorded a couple Randy Newman classics for Swim Drink Fish Music. Louisiana on.soundcloud.com/s3ObjiIYcSjK... Burn On on.soundcloud.com/9ev7CWBa2cVz...

Ten of millions in advertising behind plan to use public money to build new nuclear plants on our Great Lakes without our informed consent. The public needs an accounting. open.substack.com/pub/waterkee...

The Vanishing Guardrail: How Ontario Hollowed Out Environmental Assessment In 1976, Ontario was a global leader.

open.substack.com/pub/waterkee...

The Vanishing Guardrail: How Ontario Hollowed Out Environmental Assessment In 1976, Ontario was a global leader.

So many big energy, transportation mining projects in Ontario and Canada being proposed yet so little known about public process for decision making. Once admired around the work, let’s discuss the vanishing guardrail. @swimdrinkfish open.substack.com/pub/waterkee...

At the Water’s Edge: My Birthday Reflections on Being a Waterkeeper — Swim Drink Fish Last week, I celebrated another year on this beautiful planet, in this remarkable country. Birthdays have a way of making you pause—of taking stock of where you are, and where you’re headed. Especiall...

Not surprisingly, turning 64 has a built in Paul McCartney soundtrack. However, there is wisdom to be deciphered as well. At the Water’s Edge: My Birthday Reflections on Being a Waterkeeper — @swimdrinkfish www.swimdrinkfish.ca/blog/at-the-...

Q: What is the secret to ensuring your river, lake or seashore remains healthy, vibrant and ecologically intact? A: practice & and work. Here is your checklist & clean water regime. ⁦‪@swimdrinkfish‬⁩ ⁦‪@Waterkeeper‬⁩

Proximity to nuclear power plants associated with increased cancer mortality | Harvard T.H. Chan School of Public Health U.S. counties located closer to operational nuclear power plants have higher rates of cancer mortality than those located farther away, according to a new Harvard Chan School study.

Study on increased risk of cancer near nuclear facilities. Canada? Ontario? Great Lakes states provinces countries? Any comment? hsph.harvard.edu/news/proximi...

Thanks Dave!

Wesleyville, Lake Ontario and the Price of Silence I drove past Wesleyville yesterday.

open.substack.com/pub/waterkee...

Wesleyville, Lake Ontario and the Price of Silence I drove past Wesleyville yesterday.

Wesleyville. Lake Ontario. Nuclear. open.substack.com/pub/waterkee...

Heads up Canada. What an awesome game. We lost in end at 3 x 3 and a hot goalie. Maybe we wanted it too much. given taunts from our opponent. That said…hockey keeps educating & making Canadian boys and girls wealthy, healthy & wise. Still our game. 🇨🇦♥️🇨🇦 best

All eyes on Italy this morning

Turned cold again today. Hiding behind the barn to block the north wind

It is only a hockey game; but, it feels a lot bigger. Pulling it out of the fire - 2 games in a row……incredible. Go Canada Go. Our country. Our team. Our flag

Thanks everyone for all the nice notes and well wishes. Mean a great deal. Grateful. Look
Forward to seeing many of you this year for work, play or just hanging. Best

Toronto is a sunrise city. Waking up to 64 years on this beautiful planet. Grateful