Water hardness in Severn
Severn, Ontario tap water is hard, drawn from groundwater (municipal wells). Here is what it means at home, and the source.
What this means at home
Noticeable scale on fixtures and in kettles and water heaters; many homes choose to soften.
Range compiled from 2025 Schedule 22 summary reports for Severn's six municipal systems: Bass Lake Woodlands 265, Coldwater 303, Sandcastle Estates 126, Severn Estates 185, Washago 129 and Westshore 137 mg/L as CaCO3.
A softener is the usual call here. Because the number moves around the city, test your own tap before you buy or set one.
New to this? Read hard water, explained, including whether it is safe to drink and how to test your tap.
The number, in real terms
At 126-303 mg/L as CaCO3 mg/L (7.4 to 17.7 grains per gallon), a four-person Severn household puts roughly 3,772 grains of hardness a day through its plumbing (industry sizing convention: about 300 US gallons a day). A common 32,000-grain softener would regenerate about every 8 days here; that regeneration cadence, not the sticker size, is what to match to this water when you buy.
Scale ceiling: every 1,000 litres heated can leave at most 215 grams of scale, because that is the total mineral carried at 126-303 mg/L as CaCO3 mg/L. Real kettles and water heaters precipitate a fraction of that, but the ceiling scales with the number: Severn's hard water earns its reputation for chewing through heater elements.
How this is calculated: grains per gallon = mg/L divided by 17.1; daily grain load = gpg x 300 US gallons (the softener trade sizes in US gallons, four-person household); regeneration interval = 32,000 grains divided by the daily load; scale ceiling = mg/L carried per 1,000 L. The input figure is Township of Severn's own published number, checked 2026-07-03. Full method on the methodology page.
Severn water hardness questions
How hard is the water in Severn?
Severn's tap water is hard, about 126-303 mg/L as CaCO3 mg/L as calcium carbonate (7.4 to 17.7 grains per gallon), drawn from groundwater (municipal wells). Figure from Township of Severn, last checked 2026-07-03.
Do I need a water softener in Severn?
At this hardness, most Severn homes run a softener: it cuts the scale that shortens the life of water heaters and appliances. Test your own street first, since the number swings by neighbourhood here, then size the softener to that.
How does Severn compare with nearby towns?
Closest verified figures: Cavan Monaghan at 220 mg/L as CaCO3 mg/L, York, Regional Municipality of at 116 to 329 mg/L, Kawartha Lakes at 25 to 380 mg/L across 21 drinking water systems mg/L. Severn sits at 126-303 mg/L as CaCO3 mg/L, all measured as calcium carbonate.
Source
Source: Township of Severn, last checked 2026-07-03. Hardness varies by neighbourhood, season, and which well or plant serves your street, especially on groundwater systems. These are the municipal published figures as of the verified date, good for planning, not a substitute for a home test or your utility's current report.
Compare nearby verified figures: Cavan Monaghan (220 mg/L as CaCO3 mg/L), York, Regional Municipality of (116 to 329 mg/L), Kawartha Lakes (25 to 380 mg/L across 21 drinking water systems mg/L). Or see every municipality.