Hardness
Soft
46.5 PPM · 2.7 GPG
Local water dashboard
Official source aggregationWater quality in Knightdale, NC 27545
A source-transparent look at local hardness, associated public water systems, EPA compliance history, and the measurements that are—and are not—available for Wake County.
2 active health-based violations
- Primary matched system
- Rockbridge S/d
- Source water
- Groundwater
- County
- Wake County
- Profile updated
At a glance
What the current records say
EPA quarter 2026Q2
Compliance screen
Review needed
2 active health-based records
Lead 90th percentile
0.003 mg/L
20% of action level
Utility match
10 systems
Serves 1,042 people system-wide
Hardness meter
How hard is the water?
Estimated local hardness
USGS hardness classification scale
46.5 PPM
Soft
0–59Moderate
60–120Hard
121–180Very hard
181+
0–59Moderate
60–120Hard
121–180Very hard
181+
Parts per million
46.5
mg/L as CaCO₃ equivalent
Grains per gallon
2.7
1 GPG ≈ 17.1 PPM
What this means at home
At 46.5 PPM, mineral scale can build up on fixtures and heating elements, reduce soap lather, and leave visible spotting. Hardness is primarily an aesthetic and appliance concern—not itself a tap-water safety rating.
USGS sites used
44
Nearest site
2.9 mi
Observation range
Aug 2, 2016–Aug 28, 2024
Estimate confidence
Moderate
Median of the latest qualifying hardness observation at each nearby monitoring site. Nearest monitoring location: WK-426 FARMWELL RD NEAR RALEIGH, NC BEDROCK (Well).USGS source documentation ↗
Regional context
Is 27545 typical?
These comparisons use other indexed ZIP estimates, not utility tap samples. They help show local context without replacing a household test.
Knightdale median
47 PPM
About the same1 indexed ZIP readings · Range 46.5–46.5 PPM
North Carolina median
41 PPM
6 PPM higher519 indexed ZIP readings · Range 4.7–267.5 PPM
EPA benchmark screen
Contaminant snapshot
Available numerical results from associated SDWIS community water systems, compared with the applicable action level or federal MCL. Federal measured-value coverage is incomplete.
1 pass3 fail
Lead (PB90)
0.003 mg/L
Reported Dec 31, 2025
Copper (CU90)
1.63 mg/L
Reported Dec 31, 2020
Numerical coverage
4 comparable results
Missing values remain blank; absence is not treated as a pass.
Lead (90th percentile)
Measured in mg/L
Local 0.003
EPA limit 0.015
Copper (90th percentile)
Measured in mg/L
Local 1.63
EPA limit 1.3
Gross Alpha, Excl. Radon and U
Measured in PCI/L
Local 33
EPA limit 15
Combined Uranium
Measured in PCI/L
Local 33.1
EPA limit 30
Share of EPA benchmark
100% line = listed limit
2026Q2
- All records
- 93
- Health-based
- 23
- Active health-based
- 2
| Contaminant or rule | System | Status | Period |
|---|---|---|---|
| Gross Alpha, Excl. Radon and UHealth-basedReported 33 PCI/L · MCL 15 | NC0392341 | Addressed | Apr 1, 2026through Jun 30, 2026 |
| Combined UraniumHealth-basedReported 33.1 PCI/L · MCL 30 | NC0392341 | Addressed | Apr 1, 2026through Jun 30, 2026 |
| Public Notice | NC4092073 | Addressed | Mar 2, 2026 |
| Public Notice | NC4092073 | Addressed | Mar 2, 2026 |
| Revised Total Coliform Rule | NC4092073 | Archived | Feb 1, 2026through Feb 28, 2026 |
| Chlorine | NC4092073 | Resolved | Feb 1, 2026through Feb 28, 2026 |
| Revised Total Coliform Rule | NC4092073 | Archived | Jan 1, 2026through Jan 31, 2026 |
| Gross Alpha, Excl. Radon and UHealth-basedReported 359 PCI/L · MCL 15 | NC4092073 | Archived | Jan 1, 2026through Mar 31, 2026 |
| Combined UraniumHealth-basedReported 55.6 PCI/L · MCL 30 | NC4092073 | Archived | Jan 1, 2026through Mar 31, 2026 |
| Gross Alpha, Excl. Radon and UHealth-basedReported 64 PCI/L · MCL 15 | NC0392341 | Archived | Jan 1, 2026through Mar 31, 2026 |
| Combined UraniumHealth-basedReported 62.5 PCI/L · MCL 30 | NC0392341 | Archived | Jan 1, 2026through Mar 31, 2026 |
| Lead and Copper Rule | NC0392158 | Addressed | Jan 1, 2026 |
| Revised Total Coliform Rule | NC4092073 | Archived | Dec 1, 2025through Dec 31, 2025 |
| Chlorine | NC4092073 | Resolved | Dec 1, 2025through Dec 31, 2025 |
| Chlorine | NC4092073 | Resolved | Nov 1, 2025through Nov 30, 2025 |
| Revised Total Coliform Rule | NC4092073 | Archived | Nov 1, 2025through Nov 30, 2025 |
| Gross Alpha, Excl. Radon and UHealth-basedReported 356 PCI/L · MCL 15 | NC4092073 | Archived | Oct 1, 2025through Dec 31, 2025 |
| Combined UraniumHealth-basedReported 55 PCI/L · MCL 30 | NC4092073 | Archived | Oct 1, 2025through Dec 31, 2025 |
| Consumer Confidence Rule | NC4092073 | Addressed | Jul 1, 2025 |
| Consumer Confidence Rule | NC0392158 | Addressed | Jul 1, 2025 |
No reported violation does not prove that every contaminant was tested or absent; SDWIS measured values are incomplete and lag state records.
Solutions matcher
Your personalized water action plan
Matched to Knightdale ZIP 27545 using 46.5 PPM nearby hardness and 4 reported measurement benchmarks.
Drinking water protection
Under-Sink Reverse Osmosis System
Copper (90th percentile), Gross Alpha, Excl. Radon and U, Combined Uranium have a measured benchmark flag or active health-based SDWIS record in this profile.
A certified multi-stage RO system targets a broader range of dissolved contaminants at the kitchen tap.
Explore under-sink filtrationAffiliate disclosure: we may earn a commission from qualifying purchases, at no added cost to you. Product matching is educational and does not replace certified water testing.
Frequently asked
Water questions for Knightdale
Is tap water safe in Knightdale?+
EPA ECHO reports 2 active health-based violations among the associated community water systems. Review the affected utility's current notice and Consumer Confidence Report.
How hard is the water?+
Nearby USGS observations produce an estimate of 46.5 PPM, or 2.7 grains per gallon, classified as soft. This is not a household tap measurement.
Do I need a water softener?+
There is no high-hardness trigger in this profile. Confirm with a tap test before buying equipment.