L

Longmont, CO

—no score

Contamination score

Higher = more contaminated vs. other cities.

0
Water sources
5
Violations
0
Pollution sources
0
Self-reported
0
Lawsuits

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Reported illness & cancer claims

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Self-reported issues

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Pollution sources & reported claims near your water

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Critical High Medium Reported claim

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Public water systems

LONGMONT CITY OF

PWSID:
CO0107485
Source:
Surface water
Serves:
102,866 people

Countryside Of Longmont

PWSID:
CO0107184
Source:
Surface water
Serves:
775 people

St Vrain MHP Llc

PWSID:
CO0107724
Source:
Surface water
Serves:
544 people

EPA & DEP violations

LONGMONT CITY OF

PWSID CO01074852 violations

  • Monitoring violation — LONGMONT CITY OF

    low severityResolved

    EPA SDWIS violation 3002688 (code 27) at LONGMONT CITY OF (PWSID CO0107485).

    EPA SDWIS · Monitoring violation · Began Jul 1, 2022 · 4 years ago · Source ↗

  • Monitoring violation — LONGMONT CITY OF

    low severityResolved

    EPA SDWIS violation 3002689 (code 27) at LONGMONT CITY OF (PWSID CO0107485).

    EPA SDWIS · Monitoring violation · Began Jul 1, 2022 · 4 years ago · Source ↗

City-wide

3 violations

  • Revised Total Coliform Rule — Other violation

    medium severityResolved

    Revised Total Coliform Rule Other violation (Resolved).

    EPA SDWIS · Other · Began Dec 31, 2025 · 7 months ago · Source ↗

  • LEAD AND COPPER RULE REVISIONS — RPT violation

    medium severityResolved

    LEAD AND COPPER RULE REVISIONS RPT violation (Resolved).

    EPA SDWIS · RPT · Began Jul 2, 2025 · 1 year ago · Source ↗

  • TTHM — MR violation

    medium severityResolved

    TTHM MR violation (Resolved).

    EPA SDWIS · MR · Began Jul 1, 2022 · 4 years ago · Source ↗

Water-related lawsuits

No lawsuits on record.

In the news & sources

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