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Lone Tree, CO Tap Water Quality 2026

Water quality report for Lone Tree, CO — PFAS, lead and copper results, violation history and state inspection findings from EPA SDWIS.

A look at Lone Tree's drinking water using EPA enforcement records: violations, lead and copper results, PFAS sampling and state inspection findings.

Main Utility: Southgate Wsd PWSID: CO0103721 Updated: 2026 Q2
✅

No federal limits exceeded on record

Lead is 9.00 ppb, 60% of the action level and no violations are open. PFAS has never been sampled at this system.

B

Lone Tree earns a B for water quality

Graded on violations and lead, with state inspection findings. PFAS not tested.

Lead: 9.00 ppb — 60% of the federal action level
PFAS never sampled at this system
No violations since 2015
No violations currently open
Lone Tree's lead level vs. all Colorado community water systems
0 ppb5 ppb10 ppb15 ppb
Lead level: 9.00 ppb — 60% of the federal action level
✓ Lower lead than 8% of Colorado utilities
Population Served
13955
~11511 connections
Water Source
Surface water
Purchased from another system — SDWIS source code SWP
Active Violations
0
None on record since 2015

Lead & Copper Testing

Lead (Pb)
90th percentile of tap samples collected across the distribution system
60% of EPA action level
9.00 ppb
Action level: 15 ppb
The 90th-percentile lead result is 9.00 ppb, 60% of the 15 ppb federal action level. The action level is a treatment trigger, not a legal maximum, and it is measured across sampled taps rather than at any single home.

Contaminant Violations (2015–Present)

✓ No violations on record for this water system.
Understanding violation types MCL violations mean a contaminant exceeded the federal maximum limit — the most serious type.
TT (Treatment Technique) violations mean required treatment procedures weren't followed, but don't necessarily mean contamination occurred.

Violation History

No violations are on record for this system since 2015. EPA records violations for every community water system, so this reflects a clean compliance history rather than missing data.

About the Main Water System

Utility Southgate Wsd
PWSID CO0103721
Water source Surface water — Purchased from another system — SDWIS source code SWP
Population served 13,955
Service connections 11,511
Systems serving this area 5
Regulator State primacy agency
Data through 2026 Q2 — EPA SDWIS

Frequently Asked Questions

Is Lone Tree tap water safe to drink? ▼
No federal limit is exceeded on record. No violations are currently open. Lead is 9.00 ppb, 60% of the action level.
Does Lone Tree water have PFAS? ▼
This system has never been sampled for PFAS. EPA's national monitoring covered systems serving 3,300 people or more, so no results exist — which is not evidence that none is present.
Who supplies water to Lone Tree? ▼
Southgate Wsd (PWSID CO0103721), one of 5 systems serving this area. Surface water. Purchased from another system — SDWIS source code SWP
When was this system last inspected? ▼
It was last inspected on 2024-12-11. Inspectors recorded 1 significant deficiency.

What Should Lone Tree Residents Do?

1
Consider a filter certified for lead
Look for NSF/ANSI 53 certification for lead reduction.
2
Check for a lead service line
Lead reaches tap water mainly through service lines and household plumbing. Suppliers now publish an inventory identifying lead lines.
3
Flush before drinking
If water has sat in pipes more than six hours, run the cold tap for two minutes before drinking or cooking.

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