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Washington Water District

What EPA’s and California’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
330 people
Connections
115
Water source
Surface water
Based in
Washington, CA
County
Nevada
Owner
Private
Hardness
Soft
The ZIP code it serves

95986

The short answer

1 result is above EPA’s legal limit, and 1 more is above the limit’s level with no violation recorded. The worst: Lead, above the action level. 1 health-based violation since 2016.

What handles it

What was found

Lead and copper: EPA SDWIS monitoring periods ending 2014 to 2023.

Haloacetic acids (HAA5), total trihalomethanes (TTHM), arsenic, chromium (total), fluoride, nitrate and uranium: California’s own results, samples taken from March 5, 2020 to July 6, 2026, with EPA’s 2012 to 2019 file for earlier years.

Above the legal limit1

Lead

Comes from pipes, often your own

Above the action level

41.4ppb

90th percentile, 2021 to 2023

In the latest period, 9 in 10 homes sampled were at or below 41.4 ppb, above EPA’s action level of 15 ppb. The action level drops to 10 ppb on Nov. 1, 2027, and this result is at or above that. EPA’s health goal for lead is zero.

What handles it

Above the limit’s level, no violation recorded1

Haloacetic acids (HAA5)

Forms or is added in treatment

Above the limit’s level, no violation

73.7ppb

Highest yearly average, 2021 to 2026

2026 average: 32.3 ppb

Averaged by year, the highest was 73.7 ppb, in 2025, above EPA’s legal limit of 60 ppb. In 2026, the latest year on file, its three samples averaged 32.3 ppb. EPA judges this limit on running averages at each sampling point, and recorded no violation for haloacetic acids (HAA5) at this utility since 2020. Results like these with no violation often include water sampled before treatment or blending; the utility’s annual report says what reaches the tap.

What handles it

No certification claim covers this compound yet.

Below EPA’s limits1

Total trihalomethanes (TTHM)

Forms or is added in treatment

Below EPA’s limits

61.9ppb

Highest yearly average, 2021 to 2026

2026 average: 37.3 ppb

Averaged by year, the highest was 61.9 ppb, in 2025, below EPA’s legal limit of 80 ppb. Its highest single sample was 68 ppb. In 2026, the latest year on file, its three samples averaged 37.3 ppb.

What handles it

  • NSF/ANSI 53 look for “Trihalomethanes (TTHM) Reduction”
  • NSF/ANSI 58 look for “Trihalomethanes (TTHM) Reduction”
5 compounds tested and not foundBelow the reporting level in every sample. Not found is not the same as zero.
  • Arsenic
  • Chromium (total)
  • Fluoride
  • Nitrate
  • Uranium

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.”

At the tap, or for the whole house?

Lead and copper usually come from pipes and fixtures inside or near your home. A whole-house system sits where water enters, so it cannot catch what your own plumbing adds after it. For those, the filter that counts is the one at the tap. 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 water filters for lead, ranked

Hardness

Soft, 22 mg/L (1.3 grains per gallon), at its one sampling point, 2019 to 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 1.3 grains per gallon, salt includedSoftener or salt-free conditioner?California water hardness, utility by utility

Violations since 2016

Contaminant or ruleTypePeriodMeasuredStatus
Lead and Copper Rule RevisionsThe required inventory of lead service lines was not completed or submitted on time.EPA: LSL InventoryOct. 17, 2024—Unaddressed
Health-based violations only. Resolved and archived mean the utility returned to compliance or the state closed the record. 7 monitoring or reporting violations not shown.

What this report can’t tell you

  • Everything else. Haloacetic acids (HAA5), total trihalomethanes (TTHM), arsenic, chromium (total), fluoride, nitrate and uranium results here are California’s own from 2020 on, with EPA’s national file for 2012 to 2019. Washington Water District’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; California’s results run from March 5, 2020 to July 6, 2026.

Testing your own tap

Washington Water District’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 California certifies.

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

  • Cranmer Engineering, Inc.

    Grass Valley, CA · about 17 miles

    Certified for bacteria, nitrate, lead and copper, metals, minerals and other inorganics

    (530) 273-7284

  • Onterris Laboratories, LLC

    El Dorado Hills, CA · about 51 miles

    Certified for organic chemicals, PFAS

    (916) 673-1520

  • Ceres Analytical Laboratory, Inc.

    El Dorado Hills, CA · about 51 miles

    Certified for organic chemicals

    (916) 932-5011

All 145 certified labs for California

Sources

PWSID CA2900523. Rebuilt from EPA data on Oct. 18, 2026.

Also in Nevada County

All California utilities

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