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Siskiyou Lake Highlands MWC

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
310 people
Connections
95
Water source
Groundwater
Based in
MT. Shasta, CA
County
Siskiyou
Owner
Private
The ZIP code it serves

96067

The short answer

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

What handles it

What was found

Lead and copper: EPA SDWIS monitoring periods ending 2006 to 2022.

Copper: EPA’s file records a utility’s copper only when it exceeds the action level. The last here was 1.7 ppm, for the period ending Dec. 31, 2007. None since is on file, so it is not counted as a current finding.

Nitrate: California’s own results, samples taken from April 14, 2020 to Sept. 13, 2022, with EPA’s 2012 to 2019 file for earlier years.

Arsenic, chromium (total) and fluoride: EPA’s compliance monitoring file, samples taken from June 12, 2017 to Oct. 8, 2019. Newer results are in the utility’s annual water quality report.

Above the health goal1

Lead

Comes from pipes, often your own

Above the health goal

1.0ppb

90th percentile, 2020 to 2022

In the latest period, 9 in 10 homes sampled were at or below 1.0 ppb, below EPA’s action level of 15 ppb. The action level drops to 10 ppb on Nov. 1, 2027. EPA’s health goal for lead is zero.

What handles it

Below EPA’s limits1

Nitrate

Comes from the source

Below EPA’s limits

0.94ppm

Highest sample; found in 6 of 6

2022 average: 0.66 ppm

The highest sample, in 2020, was 0.94 ppm, below EPA’s legal limit of 10 ppm. In 2022, the latest year on file, its two samples averaged 0.66 ppm. Earlier, from 2012 to 2019, EPA’s file shows a highest sample of 1.3 ppm, in 2012.

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.
  • Arsenic
  • Chromium (total)
  • Fluoride

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

Violations since 2016

Contaminant or ruleTypePeriodMeasuredStatus
Revised Total Coliform RuleColiform or E. coli results required a detailed review of the system, and it or its fixes were not done on time.EPA: Treatment Technique, Level 2 Assessment (RTCR)Jan. 1, 2023—Resolved
Health-based violations only. Resolved and archived mean the utility returned to compliance or the state closed the record. 1 monitoring or reporting violation not shown.

What this report can’t tell you

  • Everything else. Nitrate results here are California’s own from 2020 on, with EPA’s national file for 2012 to 2019. Arsenic, chromium (total) and fluoride come from EPA’s file alone, which ends in 2019. Siskiyou Lake Highlands MWC’s own annual report, which it must send you every year, has newer results for those and 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 April 14, 2020 to Sept. 13, 2022; EPA’s compliance samples are from June 12, 2017 to Oct. 8, 2019.

Testing your own tap

Siskiyou Lake Highlands MWC’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 2 labs California certifies closest to the area Siskiyou Lake Highlands MWC serves, in a straight line. Call first: certification is test by test, and not every lab takes samples from homeowners.

  • Pace Analytical Services, LLC - Redding

    Redding, CA · about 51 miles

    Certified for bacteria

    (530) 999-4051

  • Spring Street Analytical

    Klamath Falls, OR · about 70 miles

    Certified for bacteria, nitrate

    (541) 882-6286

All 145 certified labs for California

Sources

PWSID CA4700880. Rebuilt from EPA data on Oct. 18, 2026.

Towns it serves

Also in Siskiyou County

All California utilities

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