Larimer County, Colorado
24 ZIP codes · Avg score 54/100 · Grade D · Updated 2026-06-03
The latest EPA cycle for Larimer County covers 24 ZIP codes and shows a low safety grade — systemic compliance gaps have persisted over multiple reporting periods, and the county has not moved out of the bottom tier in recent years.
How Larimer County Compares
How Larimer County Compares
Larimer County scores 6 points below the Colorado state average (60/100) and 14 points below the national average (68/100).
Data: EPA SDWIS Last verified: 2026-06-03
ZIP Code Risk Map
Water Quality Map: Larimer County, Colorado
Each dot represents a ZIP code. Color indicates water quality grade. Tap a dot for details.
Key Risk Factors
Health risk index: 9.9 (asthma 11.2%, diabetes 7.3%)
Estimated additional annual cost per homeowner: $1,336, driven primarily by flood
Infrastructure: 0.325% avg pipe failure probability, 13% of ZIPs at high risk
43.7% of homes built before 1978 (lead paint era)
Violation History (2021–2025)
↑ Worsening trendEPA violation counts by year across Larimer County water systems. Health-based shown in red, total in blue.
Peak year: 2025 with 20 violations. Past 5 years: 54 total (54 health-based). Health-based violations are rising versus the prior 2-year window — worth closer monitoring.
Source: EPA SDWIS historical violations. Data may lag 6–12 months for the most recent year.
County Health Indicators vs National Average
Black markers indicate national averages. Source: CDC PLACES, Census ACS.
Infrastructure Overview
Sources: Census ACS (housing age), EPA SDWIS (infrastructure risk model), state bridge inspection data.
Compound Risk Breakdown
Estimated additional annual cost per homeowner: $1,336
Bar widths proportional to share of total annual risk cost. Source: compound risk model (FEMA, EPA, USGS).
Housing Age Distribution
153,934 housing units in Larimer County
Source: U.S. Census Bureau ACS B25034 (Year Structure Built).
Water Safety Affordability
How much it costs to fix water issues relative to home values in Larimer County
Remediation costs are relatively manageable for most homeowners in Larimer County, representing a small fraction of property value.
Remediation includes water filtration, lead abatement, radon mitigation, and flood protection where applicable. Source: Census ACS, EPA SDWIS.
Health Outcomes vs National Average
CDC PLACES data for Larimer County residents
Black markers = national averages. Red = above national avg. Green = below. Source: CDC PLACES, Census ACS.
Water Systems with Most Violations
Top 5 systems in Larimer County ranked by EPA violation count.
| # | Water System | Population | Violations |
|---|---|---|---|
| 1 | Ft Collins Loveland Water District | 63,532 | 106 |
| 2 | East Larimer County Water District | 27,944 | 104 |
| 3 | FT COLLINS CITY OF | 179,901 | 98 |
| 4 | Spring Canyon Water Supply District | 2,320 | 98 |
| 5 | Csu Main and West Housing Campus | 27,375 | 90 |
32 total water systems serve Larimer County.
All ZIP Codes in Larimer County
24 ZIP codes tracked in Larimer County.
| # | ZIP Code | City | Safety Score | Grade | Violations | Home Value |
|---|---|---|---|---|---|---|
| 1 | 80522 | Fort Collins | 65 | C | 10 | — |
| 2 | 80528 | Fort Collins | 65 | C | 10 | $654K |
| 3 | 80549 | Wellington | 63 | C | 14 (2 health) | $453K |
| 4 | 80523 | Fort Collins | 61 | C | 10 | — |
| 5 | 80527 | Fort Collins | 61 | C | 10 | — |
| 6 | 80545 | Red Feather Lakes | 61 | C | 15 (9 health) | $399K |
| 7 | 80553 | Fort Collins | 61 | C | 10 | — |
| 8 | 80521 | Fort Collins | 60 | C | 10 | $541K |
| 9 | 80524 | Fort Collins | 60 | C | 10 | $528K |
| 10 | 80525 | Fort Collins | 60 | C | 10 | $563K |
| 11 | 80526 | Fort Collins | 60 | C | 10 | $521K |
| 12 | 80511 | Estes Park | 59 | C | 44 (6 health) | — |
| 13 | 80539 | Loveland | 59 | C | 8 | — |
| 14 | 80517 | Estes Park | 54 | D | 44 (6 health) | $670K |
| 15 | 80538 | Loveland | 54 | D | 8 | $472K |
| 16 | 80547 | Timnath | 53 | D | 0 | $719K |
| 17 | 80513 | Berthoud | 51 | D | 8 | $558K |
| 18 | 80537 | Loveland | 49 | D | 8 | $460K |
| 19 | 80512 | Bellvue | 45 | D | 0 | $618K |
| 20 | 80515 | Drake | 45 | D | 0 | $540K |
| 21 | 80532 | Glen Haven | 45 | D | 0 | $313K |
| 22 | 80535 | Laporte | 40 | D | 0 | $392K |
| 23 | 80541 | Masonville | 40 | D | 0 | — |
| 24 | 80536 | Livermore | 34 | F | 19 | $581K |
Recommended Buyer Guides for Larimer County
While many sites publish identical guide lists across every county they cover, the selection here changes by location — driven by the EPA, NSF, FEMA, and CDC datasets that describe the actual conditions documented for this jurisdiction in the federal record.
- Best Under-Sink Reverse Osmosis Systems — Multi-contaminant removal at the kitchen tap
- Best Radon Test Kits — EPA Radon Zone 1 (highest risk) dominant in county
- Best Sump Pumps — Flood is the top compound risk factor
- Best Mold Test Kits — Flood-driven moisture and mold risk
Deep Dive Reports
Detailed analysis for Larimer County, Colorado
Overview
Larimer County in Colorado covers 24 ZIP codes with an average Home Safety Score of D (54/100).
18 of 24 ZIP codes have recorded EPA violations. 23 health-based violations have been documented.
← Back to Colorado water quality report
Data Sources
- Water quality: EPA Safe Drinking Water Information System (SDWIS)
- Home values: U.S. Census Bureau ACS (median estimates by ZCTA)
Updated daily.
What You Can Do
Larimer County has a grade of D. Here are steps to protect your household.
Test your tap water
Order a certified lab test kit ($20-$50) to check for lead, bacteria, and other contaminants specific to your ZIP code.
Consider a certified water filter
NSF-certified filters can remove most common contaminants. Match the filter to your test results for best protection. Try our filter matcher
Contact your water utility
Request the latest Consumer Confidence Report (CCR) from your water provider. It details exactly what was found in your water supply.
Check for lead in your home
43.7% of homes in this county were built before 1978. Older plumbing and solder can leach lead into drinking water, especially in the morning.