Hardness
Soft
28.3 PPM · 1.7 GPG
Local water dashboard
Official source aggregationWater quality in Siasconset, MA 02564
A source-transparent look at local hardness, associated public water systems, EPA compliance history, and the measurements that are—and are not—available for Nantucket County.
1 reported benchmark flag
- Primary matched system
- Siasconset Water Department
- Source water
- Groundwater
- County
- Nantucket County
- Profile updated
At a glance
What the current records say
EPA quarter 2026Q2
Compliance screen
No active flag
0 active health-based records
Lead 90th percentile
0 mg/L
0% of action level
Utility match
1 system
Serves 3,000 people system-wide
Hardness meter
How hard is the water?
Estimated local hardness
USGS hardness classification scale
28.3 PPM
Soft
0–59Moderate
60–120Hard
121–180Very hard
181+
0–59Moderate
60–120Hard
121–180Very hard
181+
Parts per million
28.3
mg/L as CaCO₃ equivalent
Grains per gallon
1.7
1 GPG ≈ 17.1 PPM
What this means at home
At 28.3 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
50
Nearest site
34.1 mi
Observation range
May 16, 2016–Aug 24, 2023
Estimate confidence
Low
Median of the latest qualifying hardness observation at each nearby monitoring site. Nearest monitoring location: MA-MIW 29 MASHPEE, MA (Well).USGS source documentation ↗
Regional context
Is 02564 typical?
These comparisons use other indexed ZIP estimates, not utility tap samples. They help show local context without replacing a household test.
Siasconset median
28 PPM
About the same1 indexed ZIP readings · Range 28.3–28.3 PPM
Massachusetts median
49 PPM
21 PPM lower328 indexed ZIP readings · Range 24.3–128 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 pass1 fail
Lead (PB90)
0 mg/L
Reported Dec 31, 2025
Copper (CU90)
1.49 mg/L
Reported Dec 31, 2019
Numerical coverage
2 comparable results
Missing values remain blank; absence is not treated as a pass.
Lead (90th percentile)
Measured in mg/L
Local 0
EPA limit 0.015
Copper (90th percentile)
Measured in mg/L
Local 1.49
EPA limit 1.3
Share of EPA benchmark
100% line = listed limit
2026Q2
- All records
- 3
- Health-based
- 0
- Active health-based
- 0
| Contaminant or rule | System | Status | Period |
|---|---|---|---|
| Consumer Confidence Rule | MA4197001 | Unaddressed | Jul 2, 2025 |
| Nitrate | MA4197001 | Archived | Apr 1, 2025through Jun 30, 2025 |
| Consumer Confidence Rule | MA4197001 | Resolved | Jul 1, 2022through Aug 15, 2022 |
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 Siasconset ZIP 02564 using 28.3 PPM nearby hardness and 2 reported measurement benchmarks.
Drinking water protection
Under-Sink Reverse Osmosis System
Copper (90th percentile) 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
Water questions for Siasconset
Is tap water safe in Siasconset?+
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.
How hard is the water?+
Nearby USGS observations produce an estimate of 28.3 PPM, or 1.7 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.