Utility-reported hardness
Unavailable
Ask your provider or test your tap
Local water dashboard
Official source aggregationWater quality in Koyuk, AK 99753
Regional hardness evidence, possible serving systems, EPA compliance history, and the measurements that are—and are not—available for Nome Census Area.
No active health-based violation reported
- Largest possible serving system
- Koyuk Public Water System
- Source water
- Groundwater influenced by surface water
- County
- Nome Census Area
- Profile updated
Your tap water
What does the utility report?
Match the utility name to your water bill. These results describe the utility’s water, not a test at your home. A ZIP can include several water systems.
Utility hardness unavailable in this index
Nearby river or groundwater samples cannot tell us the hardness coming out of your tap. Ask your water provider for total hardness as CaCO₃, or test it at home.
Find an official utility report →At a glance
What the current records say
EPA quarter 2026Q2
All possible systems
No active flag
0 active health-based records
Measurements by utility
Each result belongs to a specific system.
Utility match
1 system
Serves 277 people system-wide
Match the name on your water bill
Your utility’s measurements and compliance records
These are possible serving systems. A record for one system does not apply to every home in this ZIP. Confirm your provider before interpreting a measurement or notice. Federal records can lag current utility notices.
EPA snapshot: 2026Q2. Historical window begins Jan 1, 2021.
Koyuk Public Water System
AK2340167 · Groundwater influenced by surface water · 277 people served system-wide
The system names this served city; Census place overlap links the city to this ZCTA.
No active health-based record in this imported snapshot
Find this utility’s official report →Measurements (1)
An action level is a regulatory trigger, not a pass/fail health boundary. A reported zero is the value in the source record and does not establish that lead is absent at your tap.
Lead (90th percentile)
EPA SDWIS Lead and Copper Rule samples
- Reported level
- 7.0e-4 mg/L
- Action level
- 0.015 mg/L
5% of the listed benchmark
Monitoring period: Jan 1, 2023 to Dec 31, 2025
Violation history (68)
| Rule | Status | Period |
|---|---|---|
| Surface Water Treatment Rule | Archived | Mar 1, 2026 to Mar 31, 2026 |
| Surface Water Treatment Rule | Resolved | Jul 1, 2025 to Jul 31, 2025 |
| Revised Total Coliform Rule | Resolved | Jul 1, 2025 to Jul 31, 2025 |
| Chlorine | Resolved | Jul 1, 2025 to Jul 31, 2025 |
| Chlorine | Resolved | May 1, 2025 to May 31, 2025 |
| Revised Total Coliform Rule | Resolved | May 1, 2025 to May 31, 2025 |
| Surface Water Treatment Rule | Resolved | May 1, 2025 to May 31, 2025 |
| Surface Water Treatment Rule | Resolved | Nov 1, 2024 to Nov 30, 2024 |
| Chlorine | Resolved | Nov 1, 2024 to Nov 30, 2024 |
| Revised Total Coliform Rule | Resolved | Nov 1, 2024 to Nov 30, 2024 |
| LEAD AND COPPER RULE REVISIONS | Resolved | Oct 17, 2024 to Jun 11, 2025 |
| LEAD AND COPPER RULE REVISIONSHealth-based | Resolved | Oct 17, 2024 to Jun 11, 2025 |
| Interim Enhanced Surface Water Treatment Rule | Resolved | Oct 1, 2024 to Oct 31, 2024 |
| Surface Water Treatment Rule | Resolved | Oct 1, 2024 to Oct 31, 2024 |
| Interim Enhanced Surface Water Treatment Rule | Resolved | Apr 1, 2024 to Apr 30, 2024 |
| Surface Water Treatment RuleHealth-based | Resolved | Apr 1, 2024 to Apr 30, 2024 |
| Chlorine | Resolved | Jul 1, 2023 to Aug 7, 2023 |
| Revised Total Coliform Rule | Resolved | Jul 1, 2023 to Jul 31, 2023 |
| Consumer Confidence Rule | Resolved | Jul 1, 2023 to Jul 13, 2023 |
| Surface Water Treatment Rule | Resolved | Jul 1, 2023 to Jul 31, 2023 |
| Chlorine | Resolved | Apr 1, 2023 to May 8, 2023 |
| Revised Total Coliform Rule | Resolved | Apr 1, 2023 to Apr 30, 2023 |
| Surface Water Treatment Rule | Resolved | Apr 1, 2023 to Apr 30, 2023 |
| Revised Total Coliform Rule | Resolved | Mar 1, 2023 to Mar 31, 2023 |
| Surface Water Treatment Rule | Resolved | Mar 1, 2023 to Mar 31, 2023 |
| Chlorine | Resolved | Jan 1, 2023 to Mar 31, 2023 |
| Revised Total Coliform Rule | Resolved | Nov 1, 2022 to Nov 30, 2022 |
| Surface Water Treatment Rule | Resolved | Nov 1, 2022 to Nov 30, 2022 |
| Surface Water Treatment RuleHealth-based | Resolved | Oct 1, 2022 to Oct 31, 2022 |
| Chlorine | Resolved | Oct 1, 2022 to Dec 7, 2022 |
| Surface Water Treatment RuleHealth-based | Resolved | Jul 1, 2022 to Jul 31, 2022 |
| Interim Enhanced Surface Water Treatment Rule | Resolved | Apr 1, 2022 to Apr 30, 2022 |
| Interim Enhanced Surface Water Treatment Rule | Resolved | Mar 1, 2022 to Mar 31, 2022 |
| Interim Enhanced Surface Water Treatment Rule | Resolved | Feb 1, 2022 to Feb 28, 2022 |
| Lead and Copper Rule | Resolved | Jan 1, 2022 to Dec 16, 2022 |
| Nitrate | Resolved | Jan 1, 2022 to Dec 31, 2022 |
| 1,2,4-Trichlorobenzene | Resolved | Jan 1, 2022 to Dec 31, 2022 |
| cis-1,2-Dichloroethylene | Resolved | Jan 1, 2022 to Dec 31, 2022 |
| DICHLOROMETHANE | Resolved | Jan 1, 2022 to Dec 31, 2022 |
| p-Dichlorobenzene | Resolved | Jan 1, 2022 to Dec 31, 2022 |
| Vinyl chloride | Resolved | Jan 1, 2022 to Dec 31, 2022 |
| 1,2-Dichloroethane | Resolved | Jan 1, 2022 to Dec 31, 2022 |
| Carbon tetrachloride | Resolved | Jan 1, 2022 to Dec 31, 2022 |
| 1,2-Dichloropropane | Resolved | Jan 1, 2022 to Dec 31, 2022 |
| Trichloroethylene | Resolved | Jan 1, 2022 to Dec 31, 2022 |
| Tetrachloroethylene | Resolved | Jan 1, 2022 to Dec 31, 2022 |
| Toluene | Resolved | Jan 1, 2022 to Dec 31, 2022 |
| Styrene | Resolved | Jan 1, 2022 to Dec 31, 2022 |
| o-Dichlorobenzene | Resolved | Jan 1, 2022 to Dec 31, 2022 |
| Benzene | Resolved | Jan 1, 2022 to Dec 31, 2022 |
| Ethylbenzene | Resolved | Jan 1, 2022 to Dec 31, 2022 |
| Xylenes, Total | Resolved | Jan 1, 2022 to Dec 31, 2022 |
| 1,1-Dichloroethylene | Resolved | Jan 1, 2022 to Dec 31, 2022 |
| CHLOROBENZENE | Resolved | Jan 1, 2022 to Dec 31, 2022 |
| 1,1,2-Trichloroethane | Resolved | Jan 1, 2022 to Dec 31, 2022 |
| 1,1,1-Trichloroethane | Resolved | Jan 1, 2022 to Dec 31, 2022 |
| trans-1,2-Dichloroethylene | Resolved | Jan 1, 2022 to Dec 31, 2022 |
| Surface Water Treatment Rule | Resolved | Dec 1, 2021 to Dec 31, 2021 |
| Interim Enhanced Surface Water Treatment Rule | Resolved | Dec 1, 2021 to Dec 31, 2021 |
| Revised Total Coliform Rule | Resolved | Nov 1, 2021 to Nov 30, 2021 |
| Revised Total Coliform Rule | Resolved | Oct 1, 2021 to Oct 31, 2021 |
| Revised Total Coliform Rule | Resolved | Sep 1, 2021 to Sep 30, 2021 |
| Surface Water Treatment RuleHealth-based | Resolved | Jul 1, 2021 to Jul 31, 2021 |
| Chlorine | Resolved | Jul 1, 2021 to Sep 30, 2021 |
| Revised Total Coliform Rule | Resolved | Jul 1, 2021 to Jul 31, 2021 |
| Total Haloacetic Acids (HAA5) | Resolved | Mar 1, 2021 to Feb 28, 2022 |
| TTHM | Resolved | Mar 1, 2021 to Feb 28, 2022 |
| Unspecified rule | Unaddressed | Jun 6, 2012 |
Hardness estimate unavailable
No responsible local estimate yet
We did not find enough qualifying recent USGS hardness observations within 25 miles of this ZIP centroid. We leave the value blank instead of substituting a state average. Ask the serving utility or test the household tap for a property-specific result.
Evidence-first next steps
Confirm the problem before choosing treatment
This profile can help you ask the right question. It cannot select equipment for a property without a current result from the serving utility or the tap.
Confirm the serving system
ZIP boundaries and utility service areas do not perfectly match. Verify the system on a water bill before relying on system-wide records.
Read the current utility report
Use the current Consumer Confidence Report for treated-water results and official notices.
Find an official utility report →Test for the decision you face
Ask the utility for hardness or test at the tap. For health concerns, use a certified laboratory and targeted analysis.
Convert your hardness test result →Frequently asked
Water questions for Koyuk
Is tap water safe in Koyuk?+
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?+
Utility-reported hardness is unavailable in this index. Regional samples do not establish tap-water hardness. Ask your provider or test your tap.
Do I need a water softener?+
Confirm hardness at your tap and consider actual scale or spotting before choosing treatment. Regional environmental values cannot determine whether you need a softener. A softener addresses hardness, not every contaminant.