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Malden Water Dept

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
215 people
Connections
65
Water source
Groundwater
Based in
Rosalia, WA
County
Whitman
Owner
Local government
Hardness
Moderately hard
The ZIP code it serves

99149

The short answer

Nothing in EPA’s and Washington’s records for this utility is above a health goal. That covers nitrate, arsenic and other regulated chemicals, plus lead and copper, not everything. No health-based violations on file since 2016.

What was found

Nitrate, total trihalomethanes (TTHM), fluoride, haloacetic acids (HAA5), arsenic and chromium (total): Washington’s own results, samples taken from Aug. 19, 2020 to Aug. 20, 2026, with EPA’s 2012 to 2019 file for earlier years.

Below EPA’s limits4

Nitrate

Comes from the source

Below EPA’s limits

5.1ppm

Highest sample; found in 6 of 6

2026, one sample: 5.0 ppm

The highest sample, in 2021, was 5.1 ppm, below EPA’s legal limit of 10 ppm. In 2026, the latest year on file, its one sample was 5.0 ppm. Earlier, from 2012 to 2019, EPA’s file shows a highest sample of 5.0 ppm, in 2012.

What handles it

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

Total trihalomethanes (TTHM)

Forms or is added in treatment

Below EPA’s limits

7.4ppb

Highest yearly average, 2020 to 2026

2026, one sample: 7.0 ppb

Averaged by year, the highest was 7.4 ppb, in 2023, below EPA’s legal limit of 80 ppb. In 2026, the latest year on file, its one sample was 7.0 ppb. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 4.0 ppb, in 2017.

What handles it

  • NSF/ANSI 53 look for “Trihalomethanes (TTHM) Reduction”
  • NSF/ANSI 58 look for “Trihalomethanes (TTHM) Reduction”

Fluoride

Forms or is added in treatment

Below EPA’s limits

0.22ppm

Highest yearly average, 2020

Averaged by year, the highest was 0.22 ppm, in 2020, below EPA’s legal limit of 4.0 ppm. That is the only year on file. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 0.16 ppm, in 2018.

What handles it

Haloacetic acids (HAA5)

Forms or is added in treatment

Below EPA’s limits

1.6ppb

Highest yearly average, 2020 to 2026

Averaged by year, the highest was 1.6 ppb, in 2026, below EPA’s legal limit of 60 ppb. That was also the latest year on file. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 38 ppb, in 2012.

What handles it

No certification claim covers this compound yet.

3 compounds tested and not foundBelow the reporting level in every sample. Not found is not the same as zero.
  • Arsenic
  • Chromium (total)
  • Lead

Hardness

Moderately hard, typically 108 mg/L (6.3 grains per gallon), across 2 sampling points, 2020 to 2023.

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 6.3 grains per gallon, salt includedSoftener or salt-free conditioner?Washington water hardness, utility by utility

Violations since 2016

No health-based violations on file with EPA since 2016. There are 3 monitoring or reporting violations: a sample missed, late or not reported.

What this report can’t tell you

  • Everything else. Nitrate, total trihalomethanes (TTHM), fluoride, haloacetic acids (HAA5), arsenic and chromium (total) results here are Washington’s own from 2020 on, with EPA’s national file for 2012 to 2019. Malden Water Dept’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 Aug. 19, 2020 to Aug. 20, 2026.

Testing your own tap

Malden Water Dept’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.

The 3 labs Washington certifies closest to the area Malden Water Dept serves, in a straight line. Call first: certification is test by test, and not every lab takes samples from homeowners.

  • Eurofins Spokane

    Spokane Valley, WA · about 30 miles

    Certified for bacteria, nitrate, minerals and other inorganics

    (509) 924-9200

  • Anatek Labs, Inc - Spokane

    Spokane, WA · about 31 miles

    Certified for bacteria, nitrate, lead and copper, metals, minerals and other inorganics, organic chemicals, disinfection byproducts, radioactivity

    (509) 838-3999

  • Tshimakain Creek Laboratories

    Spokane Valley, WA · about 32 miles

    Certified for bacteria, nitrate, minerals and other inorganics

    (509) 928-3577

All 84 certified labs for Washington

Sources

PWSID WA5350550. Rebuilt from EPA data on Oct. 18, 2026.

Also in Whitman County

All Washington utilities

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