Quick Answer: Edmonton water is moderately hard at approximately 7 grains per gallon (gpg) — sourced from the North Saskatchewan River. EPCOR Water Services uses chloramine disinfection. Key concerns include seasonal turbidity and potential lead exposure in homes with lead service lines (pre-1950 construction). The best solution for most Edmonton homes is a water softener for hardness, plus a carbon filter for chloramine removal, with additional lead filtration recommended for older homes.
How Hard Is Edmonton Water?
Edmonton Water Hardness Data
According to EPCOR Water Services data, Edmonton's water from the North Saskatchewan River averages about 165 milligrams per litre (mg/L) of calcium carbonate, which converts to approximately 9.6 grains per gallon (gpg). However, independent testing often shows values around 7 gpg (120 ppm). The river picks up minerals from limestone rock as it flows through Alberta, giving the water its characteristic moderate hardness. The actual hardness can vary seasonally with river flow conditions.
Where Does Edmonton Get Its Water?
Edmonton draws its water from a single source managed by EPCOR Water Services:
- North Saskatchewan River — originates in the Canadian Rockies' Columbia Icefield and flows over 1,200 km through Alberta and Saskatchewan. The river picks up significant mineral content from limestone and other sedimentary formations along its course through the Alberta plains.
- Rossdale Water Treatment Plant — located in central Edmonton, this historic plant (originally built in 1902, extensively upgraded) treats water using conventional processes: coagulation, flocculation, sedimentation, filtration, and disinfection.
- E.L. Smith Water Treatment Plant — located in southwest Edmonton, this modern plant (opened 1976) uses similar treatment processes with additional capacity to serve Edmonton's growing population.
The North Saskatchewan River watershed covers approximately 57,000 square kilometers, with water quality influenced by agricultural runoff, urban development, and natural geological processes.
How Is Edmonton Water Treated?
EPCOR uses conventional water treatment with some specific characteristics:
Chloramine Disinfection
Like Calgary, Edmonton uses chloramine (chlorine + ammonia) rather than chlorine alone. Chloramine is more stable, provides longer-lasting disinfection in the distribution system, and produces fewer disinfection byproducts like trihalomethanes (THMs).
pH Control for Corrosion
EPCOR maintains water pH around 7.8 (slightly alkaline) to balance between pipe corrosion (more acidic) and scale formation (more alkaline). This pH range minimizes both copper/lead leaching and excessive scale buildup.
Seasonal Treatment Adjustments
During spring runoff and heavy rain events, when the North Saskatchewan River experiences high turbidity, treatment plants adjust coagulation chemicals to effectively remove suspended particles.
Lead Service Line Concerns in Edmonton
Edmonton's water quality challenge is unique due to historical infrastructure:
Historical Use of Lead Pipes
Like many older North American cities, Edmonton used lead service lines (the pipe connecting homes to water mains) until the 1950s. An estimated several thousand homes still have these lead connections.
EPCOR's Replacement Program
EPCOR has an active program to identify and replace lead service lines at no direct cost to homeowners. The utility prioritizes areas with known lead lines and coordinates replacements during other infrastructure work.
Protective Measures
EPCOR adds orthophosphate to the water, which forms a protective coating inside pipes to reduce lead leaching. However, this is not 100% effective, especially if water sits stagnant in lead pipes for extended periods.
What Are the Effects of Edmonton's Moderately Hard Water?
At 7 gpg, Edmonton's water causes noticeable but manageable hard water problems:
Gradual Scale Buildup
Scale accumulates slowly in water heaters, reducing efficiency by 5–10% over several years. Appliances like dishwashers and coffee makers show mineral deposits over time, but not as rapidly as in harder water areas.
Soap and Skin Effects
Moderately hard water requires about 50% more soap than soft water to create lather. Many residents notice soap scum on shower walls and some skin dryness, especially in winter when indoor heating combines with hard water effects.
Seasonal Turbidity
During spring snowmelt and heavy rains, the North Saskatchewan River can become turbid (cloudy). While treatment plants handle this effectively, some residents may notice temporary changes in water appearance or taste during these periods.
Best Water Treatment Solutions for Edmonton Homes
Given Edmonton's water profile, treatment recommendations vary by home age and specific concerns:
1. Water Softener (Recommended)
A salt-based ion exchange water softener is recommended for Edmonton's 7 gpg water. While not as critical as in harder areas, softening prevents gradual scale buildup and improves soap efficiency. Size for 8–10 gpg capacity to allow for seasonal variation.
2. Carbon Filtration for Chloramine
Since Edmonton uses chloramine, install a carbon filter specifically designed for chloramine removal. Standard carbon filters have limited effectiveness. Look for catalytic carbon or systems with extended contact time.
3. Lead Filtration (Older Homes)
For homes built before 1950 or with known lead service lines, install a point-of-use filter certified for lead removal (NSF 53 standard) at kitchen taps. Reverse osmosis systems are also effective for lead removal.
4. Reverse Osmosis (Drinking Water)
For comprehensive contaminant removal including lead, minerals, and chloramine, a reverse osmosis system under the kitchen sink provides purified drinking water. Look for NSF/ANSI 58 and 53 certifications.
Edmonton Water Hardness vs. Other Major Cities
| City | Hardness (gpg) | Classification |
|---|---|---|
| Calgary, AB | ~9 | Hard |
| Edmonton, AB | ~7 | Moderately Hard |
| Toronto, ON | ~8 | Moderately Hard |
| Vancouver, BC | ~0.3 | Extremely Soft |
| Ottawa, ON | ~2.5–5 | Soft to Moderately Soft |
| Phoenix, AZ | ~16 | Very Hard |