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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
1,153 people
Connections
278
Water source
Groundwater
Based in
Olympia, WA
County
Thurston
Owner
Local government
Hardness
Soft
The ZIP code it serves

98506

The short answer

2 results are above EPA’s legal limit, and 1 more is above the health goal. The worst: Total trihalomethanes (TTHM), above the legal limit. 5 health-based violations since 2016.

What handles it

What was found

Total trihalomethanes (TTHM), haloacetic acids (HAA5), arsenic, nitrate, chromium (total) and fluoride: Washington’s own results, samples taken from Feb. 21, 2020 to April 8, 2026, with EPA’s 2012 to 2019 file for earlier years.

Above the legal limit2

Total trihalomethanes (TTHM)

Forms or is added in treatment

Above the legal limit

70.9ppb

Highest yearly average, 2020 to 2026

2026 average: 51.8 ppb

Averaged by year, the highest was 70.9 ppb, in 2025, below EPA’s legal limit of 80 ppb. Its highest single sample was 109 ppb. In 2026, the latest year on file, its four samples averaged 51.8 ppb. EPA judges this limit at each sampling point, and recorded a violation for total trihalomethanes (TTHM) at this utility in 2025. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 88.3 ppb, in 2016, and EPA recorded violations in 2016 and 2017.

What handles it

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

Haloacetic acids (HAA5)

Forms or is added in treatment

Above the legal limit

52.3ppb

Highest yearly average, 2020 to 2026

2026 average: 12.1 ppb

Averaged by year, the highest was 52.3 ppb, in 2021, below EPA’s legal limit of 60 ppb. Its highest single sample was 73.3 ppb. In 2026, the latest year on file, its four samples averaged 12.1 ppb. EPA judges this limit at each sampling point, and recorded a violation for haloacetic acids (HAA5) at this utility in 2022. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 45.2 ppb, in 2014.

What handles it

No certification claim covers this compound yet.

Above the health goal1

Arsenic

Comes from the source

Above the health goal

9.0ppb

Highest yearly average, 2021 to 2024

Averaged by year, the highest was 9.0 ppb, in 2024: below EPA’s legal limit of 10 ppb, but above its health goal of zero. That was also the latest year on file. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 4.8 ppb, in 2012.

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 limits1

Nitrate

Comes from the source

Below EPA’s limits

0.5ppm

Highest sample; found in 2 of 16

2026: not found

The highest sample, in 2024, was 0.5 ppm, below EPA’s legal limit of 10 ppm. In 2026, the latest year on file, it wasn’t found in any of its two samples. Earlier, from 2012 to 2019, EPA’s file shows a highest sample of 0.3 ppm, in 2014.

What handles it

  • NSF/ANSI 58 look for “Nitrate/Nitrite Reduction”
  • NSF/ANSI 53 look for “Nitrate/Nitrite (30 ppm challenge)”
3 compounds tested and not foundBelow the reporting level in every sample. Not found is not the same as zero.
  • Chromium (total)
  • Fluoride
  • 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

    Claims: Trihalomethanes (TTHM) Reduction, Arsenic (Pentavalent)<=50 ppb Reduction

    For: Total trihalomethanes (TTHM), Arsenic

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

  • NSF/ANSI 58

    Claims: Trihalomethanes (TTHM) Reduction, Arsenic (Pentavalent)<=50 ppb Reduction

    For: Total trihalomethanes (TTHM), 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

Soft, typically 57 mg/L (3.3 grains per gallon), across 3 sampling points, in 2021.

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

Violations since 2016

Contaminant or ruleTypePeriodMeasuredStatus
TTHMThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageJuly 1, 2025 to Sept. 30, 202589.8 UG/LArchived
Total Haloacetic Acids (HAA5)The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageJan. 1, 2022 to March 31, 202260.7 UG/LArchived
TTHMThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageJan. 1, 2017 to March 31, 201795.3 UG/LResolved
TTHMThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageOct. 1, 2016 to Dec. 31, 201685.1 UG/LResolved
TTHMThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageJuly 1, 2016 to Sept. 30, 201682.7 UG/LResolved
Health-based violations only. Resolved and archived mean the utility returned to compliance or the state closed the record. 21 monitoring or reporting violations not shown.

What this report can’t tell you

  • Everything else. Total trihalomethanes (TTHM), haloacetic acids (HAA5), arsenic, nitrate, chromium (total) and fluoride results here are Washington’s own from 2020 on, with EPA’s national file for 2012 to 2019. Boston Harbor’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 Feb. 21, 2020 to April 8, 2026.

Testing your own tap

Boston Harbor’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 Boston Harbor serves, in a straight line. Call first: certification is test by test, and not every lab takes samples from homeowners.

  • Thurston County Health Department Laboratory

    Olympia, WA · under a mile

    Certified for bacteria, nitrate

    (360) 867-2631

  • Olympic Analytical LLC dba Vanguard Laboratory

    Olympia, WA · about 7 miles

    Certified for bacteria, nitrate

    (360) 967-7010

  • Water Management Laboratories, Inc.

    Tacoma, WA · about 23 miles

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

    (253) 531-3121

All 84 certified labs for Washington

Sources

PWSID WA5307850. Rebuilt from EPA data on Oct. 18, 2026.

Towns it serves

Also in Thurston County

All Washington utilities

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