Toronto’s tap water has a reputation for being clean and safe — and by official standards, it is. Drawn from Lake Ontario and treated at the city’s four water treatment plants, it goes through conventional purification before disinfection. But most diners, home cooks, and even some restaurant kitchens overlook a detail: Toronto doesn’t rely on chlorine alone to keep that water safe as it travels through the distribution system. Like many major Canadian cities, Toronto uses chloramine as its secondary disinfectant. This choice has quiet but real consequences for anyone who cares about how their coffee, ice, or stock actually tastes.

If you’ve ever wondered why a $6 pour-over can taste subtly “flat” or chemical, or why restaurant ice sometimes carries a faint off-note even in a spotless kitchen, chloramine is very often the culprit — and it’s a much tougher opponent than the chlorine most standard filters are built to handle.

What Chloramine Actually Is (And Why It’s Not the Same as Chlorine)

Chloramine is formed when ammonia is added to chlorine during water treatment. Utilities have increasingly shifted toward it because it’s more chemically stable than chlorine alone, degrades more slowly as water moves through miles of underground piping, and produces fewer of the regulated disinfection by-products associated with straight chlorination. From a public health and infrastructure standpoint, it’s a smart trade-off — chloramine holds its disinfecting power longer, which matters in a city the size of Toronto where water can travel a long way between the treatment plant and your kitchen faucet.

The problem is that the same chemical stability that makes chloramine effective for municipal water systems is exactly what makes it so difficult to filter out at home. Chlorine is a comparatively reactive molecule — a standard granular or carbon-block filter can neutralize it fairly easily through simple adsorption. Chloramine’s chlorine-ammonia bond is far more stable, meaning it resists breaking down on contact with ordinary activated carbon. Most basic pitcher filters and even many higher-end carbon block filters were engineered with chlorine in mind, not chloramine, so they let a significant amount pass straight through. Removing it effectively requires catalytic carbon media—carbon that’s been structurally modified to speed up the chemical reaction needed to strip the compound apart—along with enough contact time and surface area to finish the job.

This isn’t a fringe concern. A point-of-use filtration study published by researchers at École Polytechnique Fédérale de Lausanne (EPFL) found that properly designed household filters can meaningfully reduce disinfection by-products and residual toxicity in both chlorinated and chloraminated tap water — but the researchers were careful to note that not all filtration media perform equally well, and that filter design matters enormously for actual results. In other words: the type of carbon in your filter is not a minor technical detail, especially in a chloraminated city like Toronto.

Pure Water and Taste: What Chloramine Does to Coffee, Tea, and the Palate

Ask any serious barista or sommelier, and they’ll tell you water is an ingredient, not a backdrop. Coffee is roughly 98% water, and tea isn’t far behind — which means whatever is dissolved in that water shows up directly in the cup. Chlorine has an obvious, sharp smell that most people notice immediately and instinctively filter out or boil off. Chloramine is sneakier. It doesn’t off-gas the way chlorine does, so simply letting water sit or boiling it briefly does very little to remove it. Instead, it lingers as a faint medicinal, slightly ammonia-like note that dulls the top and mid notes of specialty coffee and muddies the delicate florals in a good tea. For high-end restaurants and coffee programs built around single-origin beans or rare tea leaves, that’s a real problem — you can source the best beans in the world and still lose the nuance to what’s coming out of the tap. The same goes for wine service: sommeliers who use filtered water to cleanse the palate between pours need that water to be genuinely neutral, not carrying a chemical undertone that competes with the wine itself.

Ice Quality: The Detail Premium Bars Can’t Afford to Skip

Ice is one of the most overlooked ingredients behind a great bar program. Clear, dense, slow-melting ice doesn’t just look better in a rocks glass — it dilutes more predictably and doesn’t fight the spirit or wine it’s chilling. But ice made from unfiltered chloraminated water carries the same taste and clarity problems as the tap water it came from, and freezing doesn’t remove chloramine any more than boiling does. Cloudy or off-tasting ice cubes will quietly undercut even a flawless pour of aged whisky or a carefully selected Burgundy, which is exactly why premium bars and restaurants that take their spirits and wine service seriously invest in properly filtered water specifically for their ice program.

Cooking Quality: Stocks, Broths, and Dough Deserve Better Water

In the kitchen, water is doing more work than most diners realize. Stocks and broths are built almost entirely on the base liquid, meaning any off-flavor in the water gets concentrated and carried through the entire dish as it reduces. Bread and pasta doughs are similarly sensitive — water chemistry affects gluten development, fermentation behavior, and final flavor. Chefs at fine dining establishments who obsess over ingredient procurement and technique are, in effect, undermining that work if the water going into the pot hasn’t been properly treated for chloramine. It’s a detail that’s invisible on the menu but very much present on the plate.

Fortunately, Affordable Chloramine Removal Is Within Reach

Fortunately, chloramine removal options are available and affordable, and they don’t require a commercial-grade system to be effective. Aquarenaissance, a Canadian water filtration company, designed its PR110 filter cartridge specifically around the challenges Toronto’s water presents. Rather than relying on standard activated carbon, the PR110 uses a catalytic carbon media engineered to break down chloramine’s stable chlorine-ammonia bond far more effectively than conventional filters — the same category of media referenced in the EPFL research above as key for real-world DBP and residual-toxicity reduction. Because chloramine breakdown leaves ammonia behind as a by-product, the PR110 also contains specific media stages to address that ammonia, which is part of why filtered water treated this way comes out both odor-free and noticeably cleaner tasting rather than simply “less chlorinated.” For a restaurant, café, or home cook who wants water that won’t compete with what’s being brewed, poured, or simmered, that kind of purpose-built, made-in-Canada filtration is a small investment that shows up in every cup, glass, and pot.

The Takeaway

Toronto’s move to chloramine disinfection is a reasonable public health decision, but it does shift some responsibility onto anyone serious about food and drink quality. Standard filters built for chlorine simply aren’t doing the job anymore, and the difference is tasteable — in coffee, in a wine glass full of ice, and in a well-reduced stock. For restaurants, home cooks, and chefs, understanding why chloramine is harder to remove is the first step toward solving the problem, rather than assuming filtered water is filtered water.