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Northport Water System

What EPA’s and Washington’s records show in this utility’s water: nitrate, arsenic and other regulated chemicals; lead and copper; and violations since 2016, with the certification that handles each result.

Serves
290 people
Connections
225
Water source
Groundwater
Based in
Northport, WA
County
Stevens
Owner
Local government
Hardness
Very hard
The ZIP code it serves

99157

The short answer

1 result is above the health goal. The worst: Arsenic, above the health goal. 1 health-based violation since 2016.

What handles it

What was found

Arsenic, nitrate, fluoride and chromium (total): Washington’s own results, samples taken from Jan. 14, 2020 to Sept. 22, 2026, with EPA’s 2012 to 2019 file for earlier years.

Above the health goal1

Arsenic

Comes from the source

Above the health goal

1.4ppb

Highest yearly average, 2025

Averaged by year, the highest was 1.4 ppb, in 2025: below EPA’s legal limit of 10 ppb, but above its health goal of zero. Its highest single sample was 4.3 ppb. That is the only year on file. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 5.5 ppb, in 2018.

What handles it

  • NSF/ANSI 58 look for “Arsenic (Pentavalent)<=50 ppb Reduction”
  • NSF/ANSI 53 look for “Arsenic (Pentavalent)<=50 ppb Reduction”

Below EPA’s limits3

Nitrate

Comes from the source

Below EPA’s limits

7.5ppm

Highest sample; found in 86 of 91

2026 average: 5.2 ppm

The highest sample, in 2023, was 7.5 ppm, below EPA’s legal limit of 10 ppm. In 2026, the latest year on file, its nine samples averaged 5.2 ppm. Earlier, from 2012 to 2019, EPA’s file shows a highest sample of 21 ppm, in 2018, and EPA recorded a violation in 2017.

What handles it

  • NSF/ANSI 58 look for “Nitrate/Nitrite Reduction”
  • NSF/ANSI 53 look for “Nitrate/Nitrite (30 ppm challenge)”

Fluoride

Forms or is added in treatment

Below EPA’s limits

0.22ppm

Highest yearly average, 2025

Averaged by year, the highest was 0.22 ppm, in 2025, below EPA’s legal limit of 4.0 ppm. Its highest single sample was 0.25 ppm. That is the only year on file. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 0.25 ppm, in 2018.

What handles it

Chromium (total)

Comes from the source

Below EPA’s limits

1.0ppb

Highest yearly average, 2025

Averaged by year, the highest was 1.0 ppb, in 2025, below EPA’s legal limit of 100 ppb. Its highest single sample was 1.8 ppb. That is the only year on file.

What handles it

One compound tested and not foundBelow the reporting level in every sample. Not found is not the same as zero.
  • Lead

What handles it

A certification covers specific claims, not a whole standard. Look for these claims on the certifier’s listing, not the box. Wording varies a little: NSF writes “Lead Reduction,” WQA just “Lead.”

  • NSF/ANSI 53

    Claim: Arsenic (Pentavalent)<=50 ppb Reduction

    For: Arsenic

    Other certifiers’ wording: Arsenic (III) (50 ppb influent level)

  • NSF/ANSI 58

    Claim: Arsenic (Pentavalent)<=50 ppb Reduction

    For: Arsenic

    Other certifiers’ wording: Arsenic (Pentavalent)<=300 ppb Reduction; Arsenic (V) (300 ppb influent level)

At the tap, or for the whole house?

These come with the water itself, so a whole-house system certified for the same claims treats every tap and shower. A filter at the tap treats drinking water for much less. How whole-house systems compare.

Filters with those claims on a certifier’s listing

Disclosure: TapBuff earns a commission if you buy through some links on this page. It does not change which standard or filter we name. As an Amazon Associate, TapBuff earns from qualifying purchases. How TapBuff makes money

Compare five-year costs

The best reverse osmosis systems, ranked

Hardness

Very hard, typically 386 mg/L (22.6 grains per gallon), across 3 sampling points, in 2025.

Hardness is calcium and magnesium. EPA sets no limit for it: it shows up as scale on fixtures and in water heaters, and as soap that won’t lather. USGS calls water above 60 mg/L moderately hard, above 120 hard and above 180 very hard.

Softeners compared at 22.6 grains per gallon, salt includedSoftener or salt-free conditioner?Washington water hardness, utility by utility

Violations since 2016

Contaminant or ruleTypePeriodMeasuredStatus
NitrateA sample was above the legal limit, for a contaminant judged one sample at a time.EPA: Maximum Contaminant Level Violation, Single SampleJan. 1, 2017 to Dec. 31, 201713 MG/LResolved
Health-based violations only. Resolved and archived mean the utility returned to compliance or the state closed the record. 22 monitoring or reporting violations not shown.

What this report can’t tell you

  • Everything else. Arsenic, nitrate, fluoride and chromium (total) results here are Washington’s own from 2020 on, with EPA’s national file for 2012 to 2019. Northport Water System’s own annual report, which it must send you every year, has the contaminants this page does not show.

  • Your own plumbing. Lead results are the 90th percentile across homes the utility samples. Your home’s service line, solder and fixtures decide yours. A certified lab test is the only way to know.

  • What it means for your health. This page reports what the records show and EPA’s limits and goals; it is not medical advice. If you are worried about a health effect, talk to a doctor or your local health department.

  • Anything after the latest data. SDWIS data is from 2026 Q3; UCMR 5 didn’t sample this utility; Washington’s results run from Jan. 14, 2020 to Sept. 22, 2026.

Testing your own tap

Northport Water System’s results are for the water it sends out. What your own service line, solder and fixtures add shows up only in a test of your tap, by a lab Washington certifies.

No lab Washington certifies is within 75 miles of the area Northport Water System serves on the state’s list. Some take samples by mail; the state’s page lists them all.

All 84 certified labs for Washington

Sources

PWSID WA5361850. Rebuilt from EPA data on Oct. 18, 2026.

Towns it serves

Also in Stevens County

All Washington utilities

What to do next