Hardness
Soft
36.7 PPM · 2.1 GPG
Local water dashboard
Official source aggregationWater quality in Nondalton, AK 99640
A source-transparent look at local hardness, associated public water systems, EPA compliance history, and the measurements that are—and are not—available for Lake And Peninsula Borough.
1 reported benchmark flag
- Primary matched system
- Nondalton
- Source water
- Surface water
- County
- Lake And Peninsula Borough
- 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
0.002 mg/L
13% of action level
Utility match
1 system
Serves 205 people system-wide
Hardness meter
How hard is the water?
Estimated local hardness
USGS hardness classification scale
36.7 PPM
Soft
0–59Moderate
60–120Hard
121–180Very hard
181+
0–59Moderate
60–120Hard
121–180Very hard
181+
Parts per million
36.7
mg/L as CaCO₃ equivalent
Grains per gallon
2.1
1 GPG ≈ 17.1 PPM
What this means at home
At 36.7 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
1
Nearest site
46.3 mi
Observation range
Jan 13, 2016–Aug 17, 2017
Estimate confidence
Low
Median of the latest qualifying hardness observation at each nearby monitoring site. Nearest monitoring location: CHULITNA R 5MI AB MOUTH NR PORT ALSWORTH AK (Stream).USGS source documentation ↗
Regional context
Is 99640 typical?
These comparisons use other indexed ZIP estimates, not utility tap samples. They help show local context without replacing a household test.
Nondalton median
37 PPM
About the same1 indexed ZIP readings · Range 36.7–36.7 PPM
Alaska median
83 PPM
46 PPM lower18 indexed ZIP readings · Range 36.7–199 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)
0.002 mg/L
Reported Dec 31, 2025
Copper (CU90)
2.21 mg/L
Reported Dec 31, 2014
Numerical coverage
2 comparable results
Missing values remain blank; absence is not treated as a pass.
Lead (90th percentile)
Measured in mg/L
Local 0.002
EPA limit 0.015
Copper (90th percentile)
Measured in mg/L
Local 2.21
EPA limit 1.3
Share of EPA benchmark
100% line = listed limit
2026Q2
- All records
- 352
- Health-based
- 9
- Active health-based
- 0
| Contaminant or rule | System | Status | Period |
|---|---|---|---|
| Revised Total Coliform Rule | AK2260260 | Resolved | Jan 1, 2026through Jan 31, 2026 |
| Surface Water Treatment Rule | AK2260260 | Archived | Jan 1, 2026through Jan 31, 2026 |
| Surface Water Treatment Rule | AK2260260 | Archived | Dec 1, 2025through Dec 31, 2025 |
| Surface Water Treatment RuleHealth-based | AK2260260 | Archived | Dec 1, 2025through Dec 31, 2025 |
| Chlorine | AK2260260 | Archived | Dec 1, 2025through Dec 31, 2025 |
| Chlorine | AK2260260 | Archived | Nov 1, 2025through Nov 30, 2025 |
| Surface Water Treatment Rule | AK2260260 | Archived | Nov 1, 2025through Nov 30, 2025 |
| Interim Enhanced Surface Water Treatment Rule | AK2260260 | Archived | Nov 1, 2025through Nov 30, 2025 |
| Revised Total Coliform Rule | AK2260260 | Resolved | Oct 1, 2025through Oct 31, 2025 |
| Consumer Confidence Rule | AK2260260 | Unaddressed | Oct 1, 2025 |
| Chlorine | AK2260260 | Archived | Oct 1, 2025through Oct 31, 2025 |
| Surface Water Treatment Rule | AK2260260 | Archived | Oct 1, 2025through Oct 31, 2025 |
| Revised Total Coliform Rule | AK2260260 | Resolved | Sep 1, 2025through Sep 30, 2025 |
| Chlorine | AK2260260 | Archived | Sep 1, 2025through Sep 30, 2025 |
| Surface Water Treatment RuleHealth-based | AK2260260 | Resolved | Sep 1, 2025through Sep 30, 2025 |
| Surface Water Treatment Rule | AK2260260 | Archived | Sep 1, 2025through Sep 30, 2025 |
| Chlorine | AK2260260 | Resolved | Jul 1, 2025through Jul 31, 2025 |
| Lead and Copper Rule | AK2260260 | Resolved | Jul 1, 2025through Nov 3, 2025 |
| Revised Total Coliform Rule | AK2260260 | Resolved | Jul 1, 2025through Jul 31, 2025 |
| Surface Water Treatment Rule | AK2260260 | Resolved | Jul 1, 2025through Jul 31, 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 Nondalton ZIP 99640 using 36.7 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 Nondalton
Is tap water safe in Nondalton?+
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 36.7 PPM, or 2.1 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.