Castle Rock, CO: 12 Violations — 68/100 (2026)
3 ZIP codes · 7 water systems · Updated 2026-06-03
Unlike higher-rated cities in CO, Castle Rock carries a fair number of documented violations — the pattern of compliance gaps keeps the city in the middle tier of EPA safety rankings.
How Castle Rock Compares
Data: EPA SDWIS Last verified: 2026-06-03
Castle Rock Water: The Quick Version
- Your city's water systems recorded 12 violations in the past 5 years.
- Average lead level: 0.002 mg/L.
- Homes built before 1986: 12% — older plumbing may contain lead solder.
- Estimated remediation: $2,933 per household.
- CDC health risk index: 9.36.
Water Systems Serving Castle Rock
Water delivery in Castle Rock, CO is handled by 3 utilities rather than a single system — drawn from 7 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 3 ZIP codes in Castle Rock, Colorado (population ~99,741), covering 7 community water systems serving approximately 203,645 people region-wide.
3 of 3 ZIP codes (100%) have recorded EPA violations. All violations are monitoring/reporting type.
Home Safety Score
Average Home Safety Score for Castle Rock: 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
Castle Rock water systems draw from: Groundwater, Surface water.
Lead & Copper
- Average lead level (90th percentile): 0.0020 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): 3 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.
Top Contaminants
| Contaminant | Category | Violations | ZIPs Affected |
|---|---|---|---|
| E. coli | Microbiological | 8 | 3 |
| Gross Beta | Radionuclides | 4 | 3 |
| Lead and Copper Rule | Treatment Technique | 4 | 3 |
Areas with Most Violations
| ZIP Code | Safety Score | Violations | Health-Based | System |
|---|---|---|---|---|
| 80104 | C | 4 | 0 | Castle Rock Town of |
| 80108 | C | 4 | 0 | Castle Rock Town of |
| 80109 | C | 4 | 0 | Castle Rock Town of |
All ZIP Codes in Castle Rock
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.
CDC Health Data for Castle Rock
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
Key Contaminants Detected in Castle Rock
Based on EPA violation records. Check your ZIP code report for system-specific contaminant data.
How Old Is Castle Rock's Housing Stock?
Housing age data helps assess potential lead pipe and infrastructure risks. Newer housing stock generally means lower plumbing-related contamination risk.
Source: U.S. Census Bureau American Community Survey (ACS).
Housing Age Profile
Lead solder was federally prohibited in new plumbing in 1986. In Castle Rock, the median build year of 2006 puts a majority of homes in the lower-risk category for that specific contamination pathway — though the pre-1986 share shown above still carries real exposure potential at the individual household level.
Most homes in Castle Rock 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.
Castle Rock: Remediation Cost in Perspective
What does remediation cost in financial context for Castle Rock homeowners? Proportionally very little — the equity share here is low, and addressing documented issues is a manageable planning question rather than a material financial burden.
Remediation costs in Castle Rock are relatively low compared to home values. The $1,933–$4,100 estimated range is a small fraction of median property value. Home values are 43% above the Colorado average.
Protecting Children from Lead in Castle Rock
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.
Older homes from the pre-rule era make up 12% of Castle Rock's inventory, a contained slice. Citywide aggregate readings stay below 0.015 mg/L under EPA Lead and Copper Rule monitoring, suggesting systemic lead is not a dominant local concern. What the aggregate cannot do is reflect conditions inside any single building, where interior plumbing age, water chemistry, and stagnation patterns interact differently than they do across thousands of service connections combined into one figure.
Sources: EPA Lead and Copper Rule, U.S. Census Bureau ACS, CDC childhood lead poisoning prevention guidelines.
Climate-Related Water Risk for Castle Rock
Flood risk in Castle Rock occupies the middle ground: 12 NFIP claims and 100% of local ZIP codes within FEMA flood zones. At that level, the risk pathways connecting flooding to water quality — treatment system stress, well infiltration, distribution backflow — become relevant considerations during significant flood events, even if day-to-day water quality is unaffected by flood history.
Castle Rock has a moderate flood history with 12 FEMA claims averaging $1,392 per payout. 100% 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>$2,933</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 Castle Rock
- 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. Filters rated for E. coli can reduce the most common contaminant found in Castle Rock's water.
- Check your home's plumbing. Homes built before 1986 may have lead solder in pipes. A licensed plumber can assess your risk.
Deep Dive Reports
Detailed analysis for Castle Rock, CO