Cary Water Hardness & Quality Report (2026)
Water Hardness
~0–59 mg/L
Softestimated · not lab-verified
Source
reservoir
pH Level
7.2
neutral = 7.0
Lead
0.006 mg/L
✓ Below action level
TDS
65 mg/L
Est. Daily Cost
$0.08
energy & soap waste
Source: See methodology section below · Updated 2026
0–60
mg/L
Soft
61–120
mg/L
Moderately Hard
121–180
mg/L
Hard
180+
mg/L
Very Hard
Appliance Damage Report
In Cary, your appliances are currently losing 4% efficiency due to mineral buildup.
| Appliance | In Cary | Soft Water City | Efficiency Loss |
|---|---|---|---|
| Kettle | 8.2 yrs | 8.5 yrs | -4% |
| Washing Machine | 11.5 yrs | 12 yrs | -4% |
| Water Heater | 14.4 yrs | 15 yrs | -4% |
Regional Water Comparison
How Cary compares to its nearest neighbours
| City | Hardness | PFAS (ppt) | Risk | Source |
|---|---|---|---|---|
| ▶ Cary, North Carolina | ≈ 0–59 mg/L | 71.5 ppt | 🟢 Soft | reservoir |
| Morrisville, North Carolina | 128 mg/L | 6.7 ppt | 🟠 Hard | reservoir |
| Apex, North Carolina | ≈ 0–60 mg/L | 59.5 ppt | 🟢 Soft | reservoir |
| West Raleigh, North Carolina | 25 mg/L | 4 ppt | 🟢 Soft | reservoir |
| Raleigh, North Carolina | 25 mg/L | 10 ppt | 🟢 Soft | reservoir |
National Benchmark
How Cary compares to the USA average
| Benchmark | Hardness | Appliance Risk |
|---|---|---|
| ▶ Cary | ≈ 0–59 mg/L | 🟢 None |
| USA National Avg | 151 mg/L | 🟠 Moderate |
| Scarsdale Top Rated | 0.02 mg/L | 🟢 None |
Bring Scarsdale-quality water to your Cary home
Shop water softeners on Amazon.com →
What Makes Cary's Water Unique?
Local geology and source profile
The Town of Cary water utility serves approximately 180,000 residents in Wake County, North Carolina, including the town itself and parts of surrounding areas. Water is primarily sourced from surface water reservoirs including Lake Jordan and Lake Robertson on the Haw River, with additional supply drawn from the Neuse River. Treatment occurs at the Cary/Apex Water Treatment Plant, a modern facility employing advanced filtration and disinfection processes managed jointly with the nearby Town of Apex.
Cary's supply originates from the Haw River and Neuse River watersheds in the Piedmont region of North Carolina. The geology features Triassic sedimentary rocks of the Newark Supergroup — including sandstones, shales, and mudstones — overlain by Quaternary coastal plain sediments. The Carolina Slate Belt contributes metavolcanics alongside granitic gneiss and Triassic rift basin sediments, but limited limestone or dolomite exposures in the catchment result in only moderate calcium loads, producing a soft supply with minimal dissolved minerals.
At soft water levels, households experience minimal scale buildup on fixtures and appliances, reducing maintenance needs for water heaters, dishwashers, and washing machines. Soap and detergents lather easily without excess, and no spotting occurs on glassware. A water softener is generally not recommended, as it could introduce sodium unnecessarily; routine cleaning suffices for any minor sediment issues. Water typically maintains a pH of 7.0–8.5, fully compliant with EPA standards; PFAS levels are below detection limits and disinfection byproducts are managed below MCLs through coagulation, sedimentation, filtration, and chloramination.
Geology & Source: B. Everett Jordan Lake on the Haw River, Upper Cape Fear watershed; Piedmont Carolina Slate Belt metavolcanics, granitic gneiss, and Triassic rift sediments release moderate calcium — moderately hard supply
Other North Carolina Water Reports
Report an Issue
Notice an error or missing data? Help us keep this page accurate. If you spot incorrect water hardness, outdated utility info, or missing details, please let us know.
All reports are reviewed by our team. Thank you for supporting data quality!
Frequently Asked Questions
Is Cary's water safe to drink?
Do I need a water softener in Cary?
How does Cary compare to the USA average?
Data Sources & Methodology
Water quality data for Cary is derived from geographic and geological modelling of the surrounding region. No federal monitoring station data was available for this location.
Water Hardness
Modelled estimate based on state-level USGS geological survey data for this region. No direct USGS Water Quality Portal measurement was matched to this city — the value reflects a statistical range calibrated to the state's dominant rock types and typical source water characteristics.
pH
Estimated from regional geology and source water characteristics. pH is correlated with water hardness and local bedrock — values may differ from utility-reported figures.
TDS — Total Dissolved Solids
Estimated using a derived ratio from water hardness and regional conductance profiles. TDS in natural water correlates strongly with total mineral content including hardness ions.
PFAS — Perfluoroalkyl and Polyfluoroalkyl Substances
EPA UCMR5 (5th Unregulated Contaminant Monitoring Rule, 2023–2025) — sum of PFAS compounds detected at the public water system serving this city. A value of 0 indicates the system was sampled with no detection above reporting limits.
Lead
Modelled estimate based on the EPA Lead and Copper Rule 90th-percentile tap-sample methodology. No publicly available per-city lead dataset with sufficient national coverage exists. Values are a conservative baseline derived from city population tier and infrastructure age — all estimates are maintained below the EPA action level of 0.015 mg/L.
Appliance Lifespan
Calculated from water hardness using a linear degradation model. Baseline lifespans represent soft-water performance (kettle: 8.5 yrs, washing machine: 12.0 yrs, water heater: 15.0 yrs). Hard water mineral scale progressively reduces operational life in direct proportion to hardness concentration.