Metals and inorganic chemicals

Copper in water reports

Copper is regulated with lead under a treatment-technique and tap-sampling action-level framework. Plumbing and corrosion control can influence results.

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EPA dataSource review:

This is a report-reading explainer. It is not a live advisory, a household result, or a personal health assessment.

Examples on this site:
3 entries from annual water reports on this site link to this explainer.
What these results show:
Annual-report data is evidence for the named report period, not live monitoring.
Does this mean a violation?:
Not necessarily. A listed result is not automatically a violation. Check the reported value, applicable limit, report period, and status together.
Check current notices:
Current instructions must come from the water provider or another appropriate official source.

Term Identity

What the term means in an annual report

Copper is a metal that may enter drinking water through plumbing materials or occur in source water, with report interpretation centered on targeted tap samples.

Why it may appear

Copper appears with lead because the rule evaluates tap samples and corrosion-control performance rather than one system-wide concentration.

How it may be printed

Reports may show a 90th-percentile copper result, action level, MCLG, sample range, sites above the action level, and sampling year.

Other names you may see
Copper
Common report labels
Copper; Lead and Copper; 90th percentile

Evidence

Official sources for this explainer

Use official federal, state, utility, or report sources before treating a page as final.

Regulatory Context

How to read the applicable rule language

Use this Copper context to read a report's printed fields; it does not replace the report or the current official rule.

Regulatory context

Framework

The Lead and Copper Rule uses a treatment technique and action level. A separate secondary copper standard concerns aesthetic effects and must not be confused with the tap-sampling action level.

Limit or program terms

  • Action level
  • MCLG
  • 90th percentile
  • Secondary standard

Units and source context

Keep the 90th-percentile result, range, unit, sites-above field, and sampling year together. Do not compare unlike primary, action-level, and secondary contexts.

What this page does not duplicate

This explainer describes how to read the report's action-level fields without duplicating a numeric regulation table.

No standalone numeric limit table is rendered here. Read the source report's printed criterion and the current official source together.

Interpretation Boundaries

What a listed result does not establish

These Copper boundaries apply to every report row connected to this explainer.

Household-level boundary

A system copper result does not establish conditions at a particular tap because plumbing, fixtures, sampling locations, and corrosion conditions differ.

What to verify next

  1. Confirm the sampling year and 90th-percentile statistic.
  2. Read the sites-above-action-level field and the unit printed in the report.
  3. Use the provider and current EPA Lead and Copper Rule page for current context.

Annual report examples

Examples of copper in water reports

Read each result with its report year, public water system, original label, units, and any printed criteria or status.

Utility report2025 report row

Copper

From Gallup Water System's 2025 report (PWSID NM3508317). Labels, values, units, criteria, and status wording are shown as printed.

Source table
Copper & Lead
Testing or report period
2023
Reported value
Amount Detected: 0.04
Reported range
Not listed in row
Unit printed in row
ppm
Criterion printed in row
Action Level: 1.3; MCLG: 1.3
Status printed in row
Violation: No

The row prints Year Sampled 2023, Action Level 1.3, fused MCLG1.3 text, Amount Detected 0.04, and Sites Above Action Level 0.

Table note: The source visually fuses the MCLG header with Copper's printed 1.3 value as MCLG1.3. The action level and MCLG values are preserved in their intended columns with the fused source text documented.

View row in report context →Open original report
Utility report2025 report row

Copper

From Silver City Water System's 2025 report (PWSID NM3522609). Labels, values, units, criteria, and status wording are shown as printed.

Source table
Lead and Copper
Testing or report period
2023
Reported value
90th Percentile: .12
Reported range
Range Low-High: 0.0038-0.2
Unit printed in row
ppm
Criterion printed in row
AL: 1.3; MCLG: 1.3
Status printed in row
MEETS EPA STANDARDS: YES

The source table does not print a sites-above-action-level column. The printed YES is scoped to this row and its displayed 2023 sample period.

View row in report context →Open original report
Utility report2025 report row

Copper

From Ruidoso Water System's 2025 report (PWSID NM3513114). Labels, values, units, criteria, and status wording are shown as printed.

Source table
Tap water samples were collected for lead and copper analyses from sample sites throughout the community
Testing or report period
2023
Reported value
Amount Detected (90th %ile): 0.20
Reported range
Range Low-High: 0.01-0.32
Unit printed in row
ppm
Criterion printed in row
AL: 1.3; MCLG: 1.3
Status printed in row
VIOLATION: No

The 2023 sample year and printed 0/30 sites-above-action-level cell are preserved without a current tap or service-line conclusion.

View row in report context →Open original report

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