Hardness
Soft
21.3 PPM · 1.2 GPG
Local water dashboard
Official source aggregationA source-transparent look at local hardness, associated public water systems, EPA compliance history, and the measurements that are—and are not—available for Williamsburg County.
At a glance
EPA quarter 2026Q2
Hardness
Soft
21.3 PPM · 1.2 GPG
Compliance screen
No active flag
0 active health-based records
Lead 90th percentile
0.0013 mg/L
9% of action level
Utility match
3 systems
Serves 7,099 people system-wide
Hardness meter
Estimated local hardness
USGS hardness classification scale
21.3 PPM
Parts per million
21.3
mg/L as CaCO₃ equivalent
Grains per gallon
1.2
1 GPG ≈ 17.1 PPM
What this means at home
At 21.3 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
56
Nearest site
19.5 mi
Observation range
Aug 1, 2016–Sep 17, 2019
Estimate confidence
Moderate
Median of the latest qualifying hardness observation at each nearby monitoring site. Nearest monitoring location: BRK- 643 (Well).USGS source documentation ↗
Regional context
These comparisons use other indexed ZIP estimates, not utility tap samples. They help show local context without replacing a household test.
Kingstree median
21 PPM
About the same1 indexed ZIP readings · Range 21.3–21.3 PPM
South Carolina median
19 PPM
About the same236 indexed ZIP readings · Range 4.2–106 PPM
EPA benchmark screen
Available numerical results from associated SDWIS community water systems, compared with the applicable action level or federal MCL. Federal measured-value coverage is incomplete.
Lead (PB90)
0.0013 mg/L
Reported Dec 31, 2025
Copper (CU90)
Not available
No numerical 90th-percentile result
Numerical coverage
2 comparable results
Missing values remain blank; absence is not treated as a pass.
Measured in mg/L
Local 0.0013
EPA limit 0.015
Measured in MG/L
Local 0.082
EPA limit 0.08
100% line = listed limit
| Contaminant or rule | System | Status | Period |
|---|---|---|---|
| E. COLI | SC4510002 | Resolved | Apr 2, 2024through May 8, 2024 |
| Total Haloacetic Acids (HAA5) | SC4510002 | Resolved | Jan 1, 2024through Dec 31, 2024 |
| TTHM | SC4510002 | Resolved | Jan 1, 2024through Dec 31, 2024 |
| TTHMHealth-basedReported 0.082 MG/L · MCL 0.08 | SC4510007 | Resolved | Oct 1, 2023through Dec 31, 2023 |
| Revised Total Coliform RuleHealth-based | SC4510007 | Resolved | Sep 1, 2023through Sep 30, 2023 |
| E. COLI | SC4510002 | Addressed | Aug 4, 2023 |
| Consumer Confidence Rule | SC4510002 | Resolved | Jul 1, 2023through Feb 21, 2025 |
| E. COLI | SC4510002 | Resolved | Sep 7, 2022through Oct 25, 2022 |
| E. COLI | SC4510002 | Resolved | Jun 28, 2022through Jun 29, 2022 |
| TTHM | SC4550001 | Resolved | Jan 1, 2022through Dec 31, 2022 |
| Total Haloacetic Acids (HAA5) | SC4550001 | Resolved | Jan 1, 2022through Dec 31, 2022 |
| Consumer Confidence Rule | SC4510002 | Resolved | Oct 1, 2021through Oct 12, 2021 |
No reported violation does not prove that every contaminant was tested or absent; SDWIS measured values are incomplete and lag state records.
Solutions matcher
Matched to Kingstree ZIP 29556 using 21.3 PPM nearby hardness and 2 reported measurement benchmarks.
Drinking water protection
TTHM has 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
EPA ECHO shows no active health-based violation for the associated systems in this reporting snapshot. This does not prove every contaminant is absent; federal records can lag and household plumbing can change tap conditions.
Nearby USGS observations produce an estimate of 21.3 PPM, or 1.2 grains per gallon, classified as soft. This is not a household tap measurement.
There is no high-hardness trigger in this profile. Confirm with a tap test before buying equipment.