Water Quality in Gresham, OR

Gresham's water quality is good overall. Hardness is low at 22 PPM, and no contaminants exceed health guidelines. Most homes here do not need a water softener.

City of Gresham · Source: Bull Run Reservoir (Portland system) · Serves 114,247 residents

22
Hardness (PPM)
33
TDS (PPM)
0.7
Chlorine (mg/L)
3
PFAS (ppt)
2
Lead (ppb)
22 PPM 0 400 Slightly Hard
CONTAMINANT LEVELS Hardness 22 PPM TDS 33 PPM PFAS 3 ppt Lead 2 ppb Chlorine 0.7 mg/L Nitrate 1 mg/L

Hardness Scale: Where Gresham Falls

Soft 060120180250400+
Generally good quality

Gresham receives Bull Run water from the Portland system, one of the softest and cleanest municipal supplies in the US.

What Gresham's Water Means for Your Home

Gresham's water is slightly hard at 22 PPM. At this level, hard water is not a significant concern for most households. Scale buildup is minimal, and a water softener would provide little measurable benefit. If you are considering water treatment in Gresham, focus on contaminant filtration rather than softening.

Beyond hardness, Gresham's water quality is generally within EPA guidelines for regulated contaminants. Chlorine is present at 0.7 mg/L as a disinfectant residual, which is normal for municipal water systems. If you notice a pool-like taste or experience dry skin, a whole-house carbon filter is the most common and affordable solution. For homeowners who want to understand the full picture, requesting your utility's annual Consumer Confidence Report provides neighborhood-level data.

ContaminantDetectedHealth GuidelineLegal LimitStatus
Hardness (as CaCO₃)22 PPM< 60 PPMNo federal limit✓ OK
Total Dissolved Solids33 PPM< 300 PPM500 PPM✓ OK
PFAS (total)3 ppt4 ppt (EPA)4 ppt (2024)✓ OK
Lead2 ppb0 ppb (no safe level)15 ppb (action level)✓ Low
Chlorine / Chloramine0.7 mg/LTaste threshold ~1.04.0 mg/L✓ Normal
Nitrate1 mg/L5 mg/L10 mg/L✓ OK

Good news for ${esc(c.city)} residents. Your water quality is generally good. Most homes in this area do not need a water softener. If you have concerns about lead (especially in buildings constructed before 1986) or chlorine taste, a point-of-use filter is the most practical and cost-effective solution.

About Gresham's Water Supply

Water Utility: City of Gresham

Water Source: Bull Run Reservoir (Portland system)

Population Served: 114,247

Hardness: 22 PPM (1.3 grains per gallon)

Water quality can vary by neighborhood and season. The values above represent typical averages reported by City of Gresham. To get exact numbers for your address, request a copy of the most recent Consumer Confidence Report (CCR) from your utility, or have your water independently tested.

Compare Gresham to Other Oregon Cities

Portland

15 PPM · Soft

Eugene

27 PPM · Slightly Hard

Salem

14 PPM · Soft

Beaverton

24 PPM · Slightly Hard

Bend

17 PPM · Slightly Hard

Medford

28 PPM · Slightly Hard

Frequently Asked Questions About Gresham Water

Is Gresham tap water safe to drink?
Gresham's water meets EPA legal standards for drinking water safety. However, legal limits and health-optimal levels are different things. Review the contaminant table above for specific numbers and how they compare to both legal limits and health guidelines.
Do I need a water softener in Gresham?
No. At 22 PPM, Gresham's water is very soft. A water softener would provide no benefit here. Focus on filtration if you have specific contaminant concerns.
What water filter is best for Gresham?
The best filter depends on which contaminants you want to address. See our softener vs. filter guide to understand the difference between these categories.
Where does Gresham's water come from?
Gresham's drinking water is sourced from Bull Run Reservoir (Portland system) and treated by City of Gresham. Gresham receives Bull Run water from the Portland system, one of the softest and cleanest municipal supplies in the US..
What is the hardness of Gresham water in grains per gallon?
Gresham's water hardness is 1.3 grains per gallon (GPG), which equals 22 parts per million (PPM). This is classified as slightly hard. To convert: 1 GPG = 17.1 PPM.
Does Gresham water damage tankless water heaters?
At 1.3 GPG, Gresham's water is unlikely to cause significant issues for tankless water heaters. However, if you notice reduced flow or efficiency over time, scale buildup could be a factor. Annual flushing with vinegar is good maintenance regardless of hardness.
Is Gresham water safe for babies and infants?
Gresham's water meets all EPA safety standards and is generally considered safe for preparing infant formula. The hardness minerals (calcium and magnesium) are not harmful. If your home has older plumbing, running cold water for 30 seconds before use is a good precaution to flush any lead from pipes.

Data sources. Water quality data compiled from EPA SDWIS, EWG Tap Water Database, USGS water hardness studies, and the City of Gresham Consumer Confidence Report. Hardness and contaminant levels represent typical average values and may vary by neighborhood and season. Last updated: 2026-02-12.