Saint John Water Is Soft

Why Is Saint John Water So Soft?

Saint John’s water measures 1.23 GPG (21.0 ppm), which puts it firmly in the soft category. That’s a far cry from the US national average of about 7.3 GPG, and it puts Saint John in the minority of North American households. Roughly 85% of US homes have hard water, but Saint John isn’t one of them. The short version: the water simply doesn’t have much chance to pick up calcium and magnesium before it reaches your tap.

The reason comes down to where the water starts and what it travels through. Saint John draws from surface water sources, meaning rivers and lakes rather than deep wells or aquifers. Surface water is naturally low in dissolved minerals compared to groundwater. Rain and snowmelt that feed these surface sources fall on terrain that’s largely granitic and igneous bedrock, common across much of New Brunswick. Granite is notoriously stingy with calcium and magnesium. Unlike limestone or dolomite, which dissolve readily and load water up with hardness minerals, granite is composed mostly of quartz and feldspar, minerals that resist dissolution. Water running over granite picks up very little in the way of hardness.

That’s the whole story, really. The water spends its time in contact with rock that doesn’t give up much, and it doesn’t linger underground where it could slowly dissolve mineral deposits over years. Surface water moves through the system relatively quickly, so there’s simply less contact time for any minerals to leach in. The result is water that’s soft right out of the source, not water that needs treatment to become soft.

It’s also worth understanding what soft water means practically. At 1.23 GPG, you’re looking at water that’s well below the 7 GPG threshold that USGS classifies as “hard” and far below the 10.5 GPG mark for “very hard.” The EPA doesn’t regulate hardness as a health hazard at all, it’s purely an aesthetic and nuisance issue. But soft water does have real practical benefits. The WQA and Battelle Memorial Institute found in a 2010 study that soft water can require up to 50% less laundry detergent and up to 70% less dish soap compared to hard water. You’re not imagining it if your soap seems to go further here than it did somewhere else.

How Saint John Compares to Nearby Cities

Saint John’s soft water stands out in a region where many communities deal with noticeably harder water. The contrast comes down to source, not luck. Cities that pull from groundwater or wells often deal with harder water because that water has filtered through mineral-rich rock and soil, dissolving calcium and magnesium along the way. Saint John, drawing from surface sources, sidesteps that entire process.

That said, it’s important not to overstate the differences. Hardness levels can vary significantly even between neighboring communities, and the specific numbers depend entirely on each city’s water source and treatment approach. What’s defensible to say is this: if you’re coming to Saint John from a community that relies on groundwater, you’ll likely notice the difference immediately. The water here doesn’t leave scale buildup on fixtures the way harder water does, and you’ll use less soap and detergent.

The practical consequences of that softness are worth appreciating. Battelle Memorial Institute and the Water Quality Research Foundation found in 2009 that hard water causes roughly 4% gas water-heater efficiency loss per 5 GPG of hardness for a typical 50-gallon-per-day household. The Department of Energy adds that just a quarter inch of scale can cause up to 40% water-heater efficiency loss. Hard water also shortens water-heater service life by about 30-50%. Based on the WQA-commissioned Battelle Memorial Institute study, hard water is estimated to cost the average affected household more each year in extra energy, premature appliance wear, and additional cleaning products — see the cost calculator on this page for the number scaled to this city’s actual hardness. The soft water here means appliances work at their rated efficiency, soap lathers properly, and you’re not fighting scale on showerheads and faucets. It’s a genuine advantage, and it’s baked into the geology of the region. Fair enough, that’s the whole story: soft water isn’t a treatment achievement here, it’s just what the local landscape naturally provides.

How does Saint John stack up against the rest of New Brunswick? It's soft at 1.23 GPG — Fredericton, Miramichi, and Moncton sit nearby with different numbers. See the full hardest-water ranking for context.

See where Saint John sits on the New Brunswick water hardness map →

Want the broader explainer on what hardness actually is and how it behaves? Read hard water vs. soft water, explained.