Pure Aqua Columbus Field Data
2026 Central Ohio Water Intelligence Report
Anonymized results from in-home water tests across Central Ohio cities and ZIP codes — January 2025 through August 2026. 103 tests across 31 cities and 37 ZIP codes.
Updated quarterlyPrivacy-safe — ZIP-level onlyField-tested by certified technicians
Data source: Pure Aqua Columbus in-home field tests using calibrated Hach and LaMotte test kits. All tests performed by WQA-certified technicians.
Privacy: No names, addresses, or identifying information collected. Location coarsened to ZIP code. Dates stored at month precision only.
Not municipal data: These are field measurements from individual homes — not Columbus Water Works or Ohio EPA CCR values. Results reflect actual tap conditions after distribution.
Region-wide summary
Across all tests in the Pure Aqua Columbus service area, Central Ohio water is consistently very hard — driven by the Columbus Limestone formation underlying most of Franklin, Delaware, and Licking Counties.
103
Total field tests
Jan 2025 – Aug 2026
31
Cities covered
37 ZIP codes
14.8 gpg
Avg hardness
Region-wide average
86%
Chose treatment
Of tested homes
Hardest water tested
Galena
Avg 19.3 gpg — max 20.2 gpg
3 tests · Delaware County
Softest water tested
Hilliard
Avg 11 gpg — min 10.5 gpg
4 tests · Franklin County
Top homeowner complaints
The primary problem homeowners reported when calling Pure Aqua Columbus for a free water test. Scale buildup and white spots — both caused by hard water — account for the majority of calls.
Scale buildup on faucets/showerheads
29%
30 tests
White spots on dishes/fixtures
17%
17 tests
Orange/rust iron stains
16%
16 tests
Water heater scale / efficiency loss
11%
11 tests
Dry skin or hair
9%
9 tests
Hardness by city
Average hardness measured at the tap across all tested homes in each city. Delaware County cities (Powell, Lewis Center, Sunbury) consistently test harder than Franklin County cities served by Columbus Water Works.
| City | County | Avg gpg | Range | Tier | Trend | Tests | ZIPs |
|---|---|---|---|---|---|---|---|
| Galena | Delaware | 19.3 | 18.5–20.2 | Extremely Hard | → | 3 | 43021 |
| Newark | Licking | 17.6 | 16.9–18.1 | Extremely Hard | → | 4 | 43055 |
| Heath | Licking | 17.2 | 16.8–17.5 | Extremely Hard | → | 2 | 43056 |
| Columbus | Franklin | 16.8 | 15.9–17.6 | Extremely Hard | ↓ | 8 | 43201432024320343204 |
| Sunbury | Delaware | 16.8 | 16.2–17.5 | Extremely Hard | → | 3 | 43074 |
| Johnstown | Licking | 16.8 | 16.4–17.2 | Extremely Hard | → | 2 | 43031 |
| Pataskala | Licking | 16.5 | 15.8–17.2 | Extremely Hard | → | 3 | 43062 |
| Pickerington | Fairfield | 16.4 | 15.5–17.1 | Extremely Hard | ↑ | 4 | 43147 |
| Plain City | Madison | 16.4 | 15.8–17.4 | Extremely Hard | → | 3 | 43064 |
| Lewis Center | Delaware | 16.1 | 15.2–16.9 | Extremely Hard | → | 4 | 43035 |
| Lancaster | Fairfield | 15.8 | 15.2–16.5 | Extremely Hard | → | 3 | 43130 |
| Circleville | Pickaway | 15.8 | 15.4–16.2 | Extremely Hard | → | 2 | 43113 |
| Powell | Delaware | 15.3 | 14.5–16.1 | Extremely Hard | → | 6 | 43065 |
| Granville | Licking | 15.2 | 14.8–15.5 | Extremely Hard | → | 2 | 43023 |
| Blacklick | Franklin | 15.2 | 14.8–15.5 | Extremely Hard | → | 2 | 43004 |
| London | Madison | 14.8 | 14.5–15.1 | Extremely Hard | → | 2 | 43140 |
| Reynoldsburg | Franklin | 14.6 | 13.9–15.2 | Extremely Hard | → | 3 | 43068 |
| New Albany | Franklin | 14.5 | 13.8–15.1 | Extremely Hard | → | 4 | 43054 |
| Canal Winchester | Franklin | 14.5 | 13.9–15.2 | Extremely Hard | → | 3 | 43110 |
| Marysville | Union | 14.3 | 13.8–15.0 | Extremely Hard | → | 3 | 43040 |
| Mount Vernon | Knox | 14.1 | 13.8–14.4 | Extremely Hard | → | 2 | 43050 |
| Dublin | Franklin | 13.6 | 12.8–14.5 | Very Hard | → | 6 | 4301643017 |
| Gahanna | Franklin | 13.5 | 12.8–14.1 | Very Hard | → | 3 | 43230 |
| Delaware | Delaware | 13.1 | 12.4–13.8 | Very Hard | → | 3 | 43015 |
| Bexley | Franklin | 12.7 | 11.9–13.4 | Very Hard | → | 3 | 43209 |
| Worthington | Franklin | 12.5 | 11.9–13.1 | Very Hard | → | 3 | 43085 |
| Westerville | Franklin | 12.1 | 11.5–12.9 | Very Hard | ↓ | 5 | 4308143082 |
| Galloway | Franklin | 11.9 | 11.5–12.2 | Very Hard | → | 2 | 43119 |
| Grove City | Franklin | 11.5 | 10.4–12.2 | Very Hard | → | 3 | 43123 |
| Upper Arlington | Franklin | 11.4 | 10.9–11.8 | Very Hard | → | 3 | 4322043221 |
| Hilliard | Franklin | 11 | 10.5–11.5 | Very Hard | → | 4 | 43026 |
Trend arrows reflect change in average hardness from the first half to the second half of the measurement period. ↑ increasing · ↓ decreasing · → stable (±0.5 gpg).
Iron hotspots
Cities where Pure Aqua field tests found elevated iron levels. The EPA secondary standard for iron is 0.3 mg/L — above this level, staining on fixtures, laundry, and appliances becomes likely. Well-water communities in Delaware and Licking Counties show the highest iron.
Galena
Delaware County
0.5 mg/L
avg iron
100% of tests exceeded 0.3 mg/L EPA secondary standard
City detail
Key metrics for each city in the Pure Aqua Columbus service area.
Galena
Delaware County · 3 tests
19.3
avg gpg
0.5
iron mg/L
7.2
avg pH
Top complaint: Orange/rust iron stains (33%)
Install rate: 100% chose treatment
Data last verified:
Newark
Licking County · 4 tests
17.6
avg gpg
0.1
iron mg/L
7.4
avg pH
Top complaint: Orange/rust iron stains (50%)
Install rate: 100% chose treatment
Data last verified:
Heath
Licking County · 2 tests
17.2
avg gpg
0.1
iron mg/L
7.4
avg pH
Top complaint: Orange/rust iron stains (50%)
Install rate: 100% chose treatment
Data last verified:
Columbus
Franklin County · 8 tests
16.8
avg gpg
0
iron mg/L
7.6
avg pH
Top complaint: White spots on dishes/fixtures (25%)
Install rate: 88% chose treatment
Data last verified:
Sunbury
Delaware County · 3 tests
16.8
avg gpg
0.1
iron mg/L
7.4
avg pH
Top complaint: Scale buildup on faucets/showerheads (33%)
Install rate: 100% chose treatment
Data last verified:
Johnstown
Licking County · 2 tests
16.8
avg gpg
0.1
iron mg/L
7.4
avg pH
Top complaint: Orange/rust iron stains (50%)
Install rate: 100% chose treatment
Data last verified:
Pataskala
Licking County · 3 tests
16.5
avg gpg
0.1
iron mg/L
7.4
avg pH
Top complaint: Orange/rust iron stains (33%)
Install rate: 100% chose treatment
Data last verified:
Pickerington
Fairfield County · 4 tests
16.4
avg gpg
0.1
iron mg/L
7.5
avg pH
Top complaint: Orange/rust iron stains (50%)
Install rate: 100% chose treatment
Data last verified:
Plain City
Madison County · 3 tests
16.4
avg gpg
0.1
iron mg/L
7.5
avg pH
Top complaint: Scale buildup on faucets/showerheads (33%)
Install rate: 100% chose treatment
Data last verified:
Lewis Center
Delaware County · 4 tests
16.1
avg gpg
0.1
iron mg/L
7.5
avg pH
Top complaint: Water heater scale / efficiency loss (25%)
Install rate: 75% chose treatment
Data last verified:
Lancaster
Fairfield County · 3 tests
15.8
avg gpg
0.1
iron mg/L
7.5
avg pH
Top complaint: Scale buildup on faucets/showerheads (33%)
Install rate: 100% chose treatment
Data last verified:
Circleville
Pickaway County · 2 tests
15.8
avg gpg
0.1
iron mg/L
7.5
avg pH
Top complaint: Scale buildup on faucets/showerheads (50%)
Install rate: 100% chose treatment
Data last verified:
Powell
Delaware County · 6 tests
15.3
avg gpg
0.1
iron mg/L
7.5
avg pH
Top complaint: Scale buildup on faucets/showerheads (33%)
Install rate: 83% chose treatment
Data last verified:
Granville
Licking County · 2 tests
15.2
avg gpg
0.1
iron mg/L
7.5
avg pH
Top complaint: Orange/rust iron stains (50%)
Install rate: 100% chose treatment
Data last verified:
Blacklick
Franklin County · 2 tests
15.2
avg gpg
0.1
iron mg/L
7.6
avg pH
Top complaint: Scale buildup on faucets/showerheads (50%)
Install rate: 100% chose treatment
Data last verified:
London
Madison County · 2 tests
14.8
avg gpg
0.1
iron mg/L
7.6
avg pH
Top complaint: Scale buildup on faucets/showerheads (50%)
Install rate: 50% chose treatment
Data last verified:
Reynoldsburg
Franklin County · 3 tests
14.6
avg gpg
0.1
iron mg/L
7.5
avg pH
Top complaint: Scale buildup on faucets/showerheads (33%)
Install rate: 100% chose treatment
Data last verified:
New Albany
Franklin County · 4 tests
14.5
avg gpg
0
iron mg/L
7.6
avg pH
Top complaint: Water heater scale / efficiency loss (25%)
Install rate: 75% chose treatment
Data last verified:
Canal Winchester
Franklin County · 3 tests
14.5
avg gpg
0.1
iron mg/L
7.5
avg pH
Top complaint: Scale buildup on faucets/showerheads (33%)
Install rate: 100% chose treatment
Data last verified:
Marysville
Union County · 3 tests
14.3
avg gpg
0.1
iron mg/L
7.6
avg pH
Top complaint: Scale buildup on faucets/showerheads (33%)
Install rate: 67% chose treatment
Data last verified:
Mount Vernon
Knox County · 2 tests
14.1
avg gpg
0.1
iron mg/L
7.5
avg pH
Top complaint: Orange/rust iron stains (50%)
Install rate: 100% chose treatment
Data last verified:
Dublin
Franklin County · 6 tests
13.6
avg gpg
0
iron mg/L
7.8
avg pH
Top complaint: Scale buildup on faucets/showerheads (33%)
Install rate: 83% chose treatment
Data last verified:
Gahanna
Franklin County · 3 tests
13.5
avg gpg
0
iron mg/L
7.6
avg pH
Top complaint: Scale buildup on faucets/showerheads (33%)
Install rate: 100% chose treatment
Data last verified:
Delaware
Delaware County · 3 tests
13.1
avg gpg
0.1
iron mg/L
7.5
avg pH
Top complaint: Orange/rust iron stains (33%)
Install rate: 100% chose treatment
Data last verified:
Bexley
Franklin County · 3 tests
12.7
avg gpg
0
iron mg/L
7.7
avg pH
Top complaint: Dry skin or hair (33%)
Install rate: 67% chose treatment
Data last verified:
Worthington
Franklin County · 3 tests
12.5
avg gpg
0
iron mg/L
7.7
avg pH
Top complaint: Scale buildup on faucets/showerheads (33%)
Install rate: 67% chose treatment
Data last verified:
Westerville
Franklin County · 5 tests
12.1
avg gpg
0
iron mg/L
7.7
avg pH
Top complaint: Chlorine smell (20%)
Install rate: 80% chose treatment
Data last verified:
Galloway
Franklin County · 2 tests
11.9
avg gpg
0
iron mg/L
7.7
avg pH
Top complaint: Scale buildup on faucets/showerheads (50%)
Install rate: 50% chose treatment
Data last verified:
Grove City
Franklin County · 3 tests
11.5
avg gpg
0
iron mg/L
7.7
avg pH
Top complaint: Scale buildup on faucets/showerheads (33%)
Install rate: 67% chose treatment
Data last verified:
Upper Arlington
Franklin County · 3 tests
11.4
avg gpg
0
iron mg/L
7.8
avg pH
Top complaint: Dry skin or hair (33%)
Install rate: 67% chose treatment
Data last verified:
Hilliard
Franklin County · 4 tests
11
avg gpg
0
iron mg/L
7.8
avg pH
Top complaint: Scale buildup on faucets/showerheads (25%)
Install rate: 75% chose treatment
Data last verified:
Methodology & data provenance
Test equipment: Hach 5B hardness test kit (±0.5 gpg accuracy), LaMotte iron colorimetric test (±0.05 mg/L), digital pH meter (±0.1 pH), HM Digital TDS-4 meter (±2% accuracy). All equipment calibrated per manufacturer schedule.
Test point: Cold water at the kitchen tap, after a 30-second flush. Results reflect actual tap conditions — not treatment plant output or distribution system averages.
Technician certification: All tests performed by WQA-certified water treatment specialists. Pure Aqua Columbus is a Westinghouse Authorized Dealer.
Privacy: No names, addresses, or identifying information collected. Location coarsened to ZIP code. Dates stored at month precision only.
Relationship to municipal data: These results are independent field measurements and may differ from Columbus Water Works, Delaware County District Water, or Ohio EPA Consumer Confidence Reports. Municipal CCRs measure water at the treatment plant; our tests measure water at the tap after distribution, which can show higher hardness and iron due to pipe leaching and distribution system effects.
Update schedule: This report is updated quarterly. The current dataset covers January 2025 through August 2026. Next update: December 2026.
API access: Aggregate data is available at
/api/water-data/city/:slug and /api/water-data/zip/:zip. Raw records are never served publicly.See your home's actual water quality
This report shows averages. Your home's water can vary by neighborhood, plumbing age, and season. A free in-home test gives you exact numbers — hardness, iron, pH, TDS, and chlorine — in 30 minutes.