Littleton, CO: High Radon Risk — 68/100 (2026)
16 ZIP codes · 10 water systems · Updated 2026-06-03
Littleton shows moderate tap water quality for CO — some areas carry documented EPA violations while others meet standards without issues.
How Littleton Compares
Data: EPA SDWIS Last verified: 2026-06-03
Water Quality Map: Littleton, CO
Each dot represents a ZIP code. Color indicates water quality grade. Tap a dot for details.
Score Distribution
Safety grade breakdown for Littleton's 16 ZIP codes.
Key Facts for Littleton Residents
- Average lead level: 0.005 mg/L.
- Homes built before 1986: 41% — older plumbing may contain lead solder.
- Estimated remediation: $2,256 per household.
- CDC health risk index: 9.92.
Littleton's Water Providers
Water delivery in Littleton, CO is handled by 3 utilities rather than a single system — drawn from 10 providers in federal records, each filing its own compliance reports and setting its own rates.
Overview
We track water quality and home safety data for 16 ZIP codes in Littleton, Colorado (population ~318,691), covering 10 community water systems serving approximately 1,452,032 people region-wide.
No EPA violations recorded across any ZIP codes in Littleton — an excellent indicator of water quality.
Home Safety Score
Average Home Safety Score for Littleton: C (68/100)
The score combines three factors:
| Factor | What It Measures |
|---|---|
| Water Quality | EPA violations and compliance history |
| Lead Levels | 90th percentile lead concentration vs EPA action level |
| Radon Risk | EPA radon zone classification |
Water Sources
Littleton water systems draw from: Groundwater, Surface water.
Lead & Copper
- Average lead level (90th percentile): 0.0050 mg/L (EPA action level: 0.015 mg/L)
- 0 ZIP codes exceed the EPA lead action level
Radon Risk
Dominant radon zone: Zone 1 (High Risk)
- Zone 1 (High): 16 ZIP codes
- Zone 2 (Moderate): 0 ZIP codes
- Zone 3 (Low): 0 ZIP codes
The EPA recommends testing homes in Zone 1 and Zone 2 areas for radon.
Areas with No Violations
| ZIP Code | Safety Score | System | Population |
|---|---|---|---|
| 80120 | C | Southwest Metropolitan Water Supply District | 48,648 |
| 80121 | B | City of Englewood | 57,332 |
| 80122 | C | Southwest Metropolitan Water Supply District | 48,648 |
| 80123 | C | Southwest Metropolitan Water Supply District | 48,648 |
| 80125 | B | Southwest Metropolitan Water Supply District | 48,648 |
| 80126 | B | Roxborough Water Supply District | 13,765 |
| 80127 | B | Southwest Metropolitan Water Supply District | 48,648 |
| 80128 | B | Southwest Metropolitan Water Supply District | 48,648 |
| 80129 | B | Southwest Metropolitan Water Supply District | 48,648 |
| 80130 | B | Southwest Metropolitan Water Supply District | 48,648 |
All ZIP Codes in Littleton
- 80120 [C]
- 80121 [B]
- 80122 [C]
- 80123 [C]
- 80125 [B]
- 80126 [B]
- 80127 [B]
- 80128 [B]
- 80129 [B]
- 80130 [B]
- 80160 [C]
- 80161 [C]
- 80162 [C]
- 80163 [C]
- 80165 [C]
- 80166 [C]
Data Sources
- Water quality: EPA Safe Drinking Water Information System (SDWIS)
- Lead/copper: EPA Lead and Copper Rule sampling data
- Radon: EPA Map of Radon Zones
Updated daily.
Littleton Community Health Snapshot
Source: CDC PLACES (County-level estimates). Water contamination can correlate with respiratory and chronic health conditions.
Compared to National Average
Vertical line = national average. ■ Above national · ■ Below national
Littleton Infrastructure Age
With 41% of homes built before 1986, lead solder in plumbing is a potential concern. The EPA banned lead solder in 1986, but many older homes retain original plumbing.
Source: U.S. Census Bureau American Community Survey (ACS).
Housing Age Profile
Pre-1986 construction carries elevated plumbing-era lead risk because lead solder was widely used before that federal ban. In Littleton, the median build year of 1988 indicates a housing stock where that older fraction represents a significant share of the residential inventory.
Most homes in Littleton were built after 1986, reducing the risk of lead contamination from plumbing. Older homes should still be tested.
Source: U.S. Census Bureau ACS B25034.
How Remediation Costs Compare in Littleton
While no remediation project is entirely without cost, the relationship between estimated remediation and property values in Littleton is notably favorable — the equity share is small enough that the household financial perspective is one of proportionality rather than pressure, and most homeowners can treat it as routine planning rather than a significant financial event.
Remediation costs in Littleton are relatively low compared to home values. The $1,494–$3,050 estimated range is a small fraction of median property value. Home values are 44% above the Colorado average.
Littleton: Lead Risk & Vulnerable Populations
Why children are most at risk: The CDC states there is no safe level of lead exposure for children. Children under 6 absorb lead more readily than adults, and even low levels can cause developmental delays, learning difficulties, and behavioral problems.
When older housing represents 41% of the local inventory or aggregate readings approach the federal action level, an in-home check becomes the standard way to translate citywide averages into the specific reality of an individual Littleton address.
Sources: EPA Lead and Copper Rule, U.S. Census Bureau ACS, CDC childhood lead poisoning prevention guidelines.
Littleton: Flood History & Water Damage Risk
Within the NFIP's national dataset, Littleton falls in moderate-exposure territory — 88 documented incidents spanning multiple decades, with 63% of local ZIP codes sitting inside FEMA flood boundaries. That combination warrants inclusion in any thorough local water quality review.
Littleton has a moderate flood history with 88 FEMA claims averaging $5,452 per payout. 63% of ZIP codes fall within FEMA flood zones. Flood events can contaminate drinking water and overwhelm treatment systems.
How flooding affects water quality: Flood events can introduce sewage, agricultural runoff, and industrial chemicals into water supplies. Even after floodwaters recede, contamination can persist in wells and aging infrastructure. Flood damage can add significantly to the estimated <strong>$2,256</strong> remediation cost per household.
Residents in flood-prone areas should consider flood insurance even outside FEMA zones — over 25% of flood claims come from low-to-moderate risk areas. After any flood event, test your water before drinking.
Source: FEMA National Flood Insurance Program (NFIP) claims data, FEMA flood zone designations.
What You Can Do in Littleton
- Test your water at home. City-level data shows averages — your tap may differ. NSF-certified test kits cost $20-40 and give results in days.
- Install a certified water filter. An NSF-certified pitcher or under-sink filter removes most common contaminants.
- Check your home's plumbing. With 41% of homes built before 1986, lead solder is a real possibility.
Deep Dive Reports
Detailed analysis for Littleton, CO