Water Quality in CASTLE ROCK, CO (80109)

EPA violation data for public water systems serving ZIP code 80109.

109

Total Violations

8

Health-Based

101

Monitoring / Reporting

97

Resolved

What does this mean?

97 of 109 violations have been resolved. 8 are health-based violations, meaning contaminant levels exceeded federal safety limits. The remaining 101 are monitoring or reporting violations (missed testing deadlines or late paperwork — not necessarily a water quality issue). Not all violations mean your water is unsafe. The EPA requires reporting even for minor administrative issues.

Water systems: 9 Population served: 122,203

Violations Detail (109 total)

ContaminantCategoryMCL LimitMeasuredDateStatusHealth Effects
Public NoticeMonitoringN/AN/AAug 15, 2025ActiveN/A
Revised Total Coliform RuleMonitoringN/AN/AJul 31, 2025ResolvedN/A
Revised Total Coliform RuleMonitoringN/AN/AJul 31, 2025ResolvedN/A
Revised Total Coliform RuleHealth-BasedN/AN/AJul 10, 2025ActiveN/A
Revised Total Coliform RuleHealth-BasedN/AN/AJul 10, 2025ActiveN/A
Public NoticeMonitoringN/AN/AJun 30, 2025ActiveN/A
Surface Water Treatment RuleMonitoringN/AN/AMay 31, 2025ResolvedN/A
Surface Water Treatment RuleMonitoringN/AN/AMay 31, 2025ResolvedN/A
Surface Water Treatment RuleMonitoringN/AN/AMay 31, 2025ResolvedN/A
Revised Total Coliform RuleMonitoringN/AN/AMay 31, 2025ResolvedN/A

Lead & Copper Levels

Violation Timeline

2025(21)

Public Notice

75

Aug 15Active

Revised Total Coliform Rule

3A

Jul 31Resolved

Revised Total Coliform Rule

3A

Jul 31Resolved

Revised Total Coliform Rule

2D

Jul 10Active

Revised Total Coliform Rule

2D

Jul 10Active

Public Notice

75

Jun 30Active

Surface Water Treatment Rule

36

May 31Resolved

Surface Water Treatment Rule

36

May 31Resolved

Surface Water Treatment Rule

36

May 31Resolved

Revised Total Coliform Rule

3A

May 31Resolved

Revised Total Coliform Rule

3A

May 31Resolved

Revised Total Coliform Rule

3A

May 31Resolved

Revised Total Coliform Rule

5A

May 20Resolved

Revised Total Coliform Rule

5A

May 20Resolved

Revised Total Coliform Rule

5A

May 20Resolved

Surface Water Treatment Rule

36

Apr 30Resolved

Surface Water Treatment Rule

36

Apr 30Resolved

Surface Water Treatment Rule

36

Apr 30Resolved

Lead and Copper Rule

66

Mar 31Resolved

Lead and Copper Rule

66

Mar 31Resolved

Lead and Copper Rule

66

Mar 31Resolved

2024(14)

Total Haloacetic Acids (HAA5)

27

Dec 31Active

Total Haloacetic Acids (HAA5)

27

Dec 31Active

TTHM

27

Dec 31Active

TTHM

27

Dec 31Active

Public Notice

75

Aug 24Active

Public Notice

76

Aug 7Active

Revised Total Coliform Rule

2D

Jul 10Active

Revised Total Coliform Rule

2D

Jul 10Active

Revised Total Coliform Rule

3A

Jun 30Resolved

Revised Total Coliform Rule

3A

Jun 30Resolved

Revised Total Coliform Rule

3A

Jun 30Resolved

Revised Total Coliform Rule

3A

May 31Resolved

Revised Total Coliform Rule

3A

May 31Resolved

Revised Total Coliform Rule

3A

May 31Resolved

How Does This Compare?

CASTLE ROCK (80109) has 109 recorded violations, including 8 health-based. 12 remain unresolved. Consider testing your tap water independently for added peace of mind.

Recommended Water Filters

Based on the contaminants detected in your area, these filter types may help improve your water quality.

Reverse Osmosis System

Highly effective at removing heavy metals, dissolved solids, and a wide range of contaminants. Recommended for homes with lead or arsenic concerns.

Targets:Lead, Copper, Arsenic, Mercury, Cadmium

Look for:NSF/ANSI 58 certified

Activated Carbon Filter

Excellent for removing chlorine, chloramine, and disinfection byproducts like THMs and HAAs. Available as pitcher filters, countertop, or under-sink units.

Targets:THMs, HAAs, Chlorine, Chloramine, Taste & Odor

Look for:NSF/ANSI 42 & 53 certified

UV Water Purifier

Uses ultraviolet light to neutralize bacteria, viruses, and parasites without chemicals. Ideal for homes with microbial contamination concerns.

Targets:E. coli, Coliform, Giardia, Cryptosporidium

Look for:NSF/ANSI 55 (Class A) certified

Always look for filters certified by NSF International for the specific contaminants you want to remove.

Nearby ZIP Codes

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