Unlike higher-rated cities in CO, Denver carries a fair number of documented violations - the pattern of compliance gaps keeps the city in the middle tier of EPA safety rankings.

Data: EPA SDWIS, FEMA NFIP, Census ACS

Water Quality in Denver

We track home safety signals for 69 ZIP codes in Denver, Colorado. EPA community-water data is directly mapped for 42 ZIP codes and 35 water systems.

41 of 42 directly mapped ZIP records with reported violation counts (98%) have recorded EPA violations - 1,357 total, including 9 health-based violations.

Average Home Safety Score: C (63/100)

Water sources: Groundwater, Surface water.

Top Contaminants

Lead Risk

• Average lead level (90th percentile): 0.0033 mg/L
• 0 of 42 ZIP codes with known status exceed the EPA lead action level
• 61% of housing built before 1986 (when lead solder was banned)
• 16% of housing built before 1950 (when lead pipes were standard)
• Median year built: 1977
• Most common estimated pipe material: Copper
• Lead exposure risk score: 48/100
• Estimated lead service line probability: 19%
• 25 ZIP codes classified as high or very high lead risk

With 61% of homes built before the 1986 lead solder ban, Denver residents - especially those in older neighborhoods - should consider testing their tap water for lead. Homes built before 1950 are at the highest risk of having lead service lines.

Housing Age Distribution

508,608 total housing units across 69 ZIP codes:

Flood Risk

FEMA National Flood Insurance Program data for Denver:

• 502 flood insurance claims on record
• $1,675,940 sum of reported building, contents, and ICC payment components
• 270 claims with payment data
• 232 claims without reported payment fields
• $6,207 average reported component sum among claims with payment data
• Dominant rated-zone value in historical claims: X (other)
• 9 of 37 ZIP codes with claim-zone records have an A/V-family dominant rated zone in those claims
• Claim-zone values are historical insurance records, not a complete current FEMA property-map inventory

Radon Risk

Dominant EPA radon zone among 69 ZIP records with zone data: Zone 1 (High Risk)

• Zone 1 (High): 69 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.

Neighborhoods by Safety Score

Safest Areas

Areas Needing Attention

What Denver Residents Can Do

Test Your Water

• Order a certified lab test - home test kits cost $20–50 and cover lead, bacteria, and common contaminants
• Request your utility's CCR (Consumer Confidence Report) - your water provider must publish this annually
• Check your ZIP code - each area in Denver has different water systems and risk levels

Filter Your Water

• NSF-certified pitcher filter removes chlorine taste and some contaminants ($20–40)
• NSF 53-certified filter for lead - recommended for homes built before 1986
• Reverse osmosis system removes 95%+ of contaminants including lead, PFAS, and nitrates ($150–400)

Test for Radon

• Denver is in a high-risk radon area
• Short-term radon test kits cost $10–25
• If levels exceed 4 pCi/L, EPA recommends professional mitigation

Stay Informed

• Visit your ZIP code report for detailed, address-level data
• Sign up for EPA water quality alerts
• Review the annual water quality report from your local utility

All ZIP Codes in Denver

• 80201
• 80202 [C] - 34 violations
• 80203 [C] - 34 violations
• 80204 [C] - 34 violations
• 80205 [C] - 34 violations
• 80206 [C] - 34 violations
• 80207 [C] - 34 violations
• 80208
• 80209 [C] - 34 violations
• 80210 [C] - 40 violations ⚠
• 80211 [C] - 34 violations
• 80212 [C] - 34 violations
• 80214 [C] - 34 violations
• 80215 [C]
• 80216 [C] - 43 violations
• 80217
• 80218 [C] - 34 violations
• 80219 [C] - 40 violations ⚠
• 80220 [C] - 34 violations
• 80221 [D] - 46 violations
• 80222 [C] - 34 violations
• 80223 [C] - 40 violations ⚠
• 80224 [C] - 34 violations
• 80225
• 80226 [C] - 35 violations
• 80227 [C] - 35 violations
• 80228 [C] - 4 violations ⚠
• 80229 [D] - 9 violations
• 80230 [C] - 34 violations
• 80231 [C] - 34 violations
• 80232 [C] - 35 violations
• 80233 [D] - 8 violations
• 80234 [D] - 21 violations ⚠
• 80235 [C] - 34 violations
• 80236 [C] - 40 violations ⚠
• 80237 [C] - 34 violations
• 80238 [C] - 34 violations
• 80239 [C] - 34 violations
• 80243
• 80244
• 80246 [C] - 35 violations
• 80247 [C] - 34 violations
• 80248
• 80249 [C] - 34 violations
• 80250
• 80251
• 80252
• 80256
• 80257
• 80259
• 80260 [F] - 42 violations ⚠
• 80261
• 80262
• 80263
• 80264 [C] - 34 violations
• 80265
• 80266 - 34 violations
• 80271
• 80273
• 80274
• 80279
• 80280
• 80281
• 80290 - 34 violations
• 80291
• 80293
• 80294 [C] - 34 violations
• 80295
• 80299

Frequently Asked Questions

Is the tap water safe to drink in Denver, CO?

The Home Safety Score is not a drinking-water grade. Denver has an average score of 63/100 (grade C) across 40 ZIP codes with complete current-model evidence. Separately, there are 1357 recorded EPA violations across 42 directly mapped ZIP records with reported counts, 9 of which are health-based. Check the specific ZIP and serving utility before drawing a water-safety conclusion.

Does Denver have lead in the water?

The average 90th-percentile lead level across Denver is 0.0033 mg/L, below the EPA action level of 0.015 mg/L. 0 of 42 ZIP codes with known action-level status exceed the EPA limit. About 61% of housing was built before 1986, when lead solder was banned.

Is Denver at risk for flooding?

FEMA data shows 502 flood insurance claim records in Denver ZIP codes, with an average reported building, contents, and ICC component sum of $6,207 among 270 claims with payment data. 232 claims lack reported payment fields and are not counted as zero. Among 37 ZIP codes with historical claim-zone values, 9 have an A/V-family dominant rated zone in those claims. Claim records do not establish current property-level flood risk; check the FEMA map for a specific address.

Are there lead pipes in Denver homes?

61% of Denver housing was built before 1986, when lead solder was common in plumbing. 16% was built before 1950, when lead pipes were standard. The most common estimated pipe material is Copper. The estimated probability of lead service lines is 19%. We recommend testing your water if your home was built before 1986.

What contaminants have been found in Denver water?

The most common contaminants by violation count are Fecal Coliform, Combined Radium, Contaminant 2005. Across 42 ZIP codes with directly mapped EPA water data, 41 have recorded EPA violations. Check your ZIP code report for the specific contaminants in your area.

Data Sources

• Water quality: EPA Safe Drinking Water Information System (SDWIS)
• Lead/copper: EPA Lead and Copper Rule sampling data
• Housing age: U.S. Census Bureau American Community Survey
• Flood data: FEMA National Flood Insurance Program
• Lead exposure: Composite risk score based on housing age, water lead levels, and service line estimates
• Radon: EPA Map of Radon Zones

Source reporting periods vary. See each cited source for its publication schedule.

Housing Age Profile

The year 1986 marks a critical threshold in residential plumbing safety: that's when the federal government banned lead solder from new construction, closing a major pathway for lead entering household drinking water via pipe joints. Denver's median build year of 1977 signals that most of the city's housing was built under the newer standard. The distribution above tells the full story - the post-1986 majority lowers aggregate risk, but the pre-1986 share still deserves scrutiny from anyone living in or purchasing an older home.

1977

Median Year Built

0%

Pre-1986 (Lead Paint Risk)

0%

Pre-1970 (Lead Pipes Risk)

Most homes in Denver 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.

Protecting Children from Lead in Denver

0.0033

mg/L Avg Lead (Limit: 0.015)

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.

Lead risk in Denver appears low overall, but individual homes may differ. Testing is the only way to confirm your water's lead content.

Sources: EPA Lead and Copper Rule, U.S. Census Bureau ACS, CDC childhood lead poisoning prevention guidelines.

Historical Flood-Claim Evidence for Denver

502

Total FEMA Flood Claims

$6,207

Avg Reported Sum With Payment Data

24%

A/V Share of Claim-Record ZIPs

Historical NFIP data for Denver contains 502 flood insurance claims. Among claims with payment data, the average reported building, contents, and ICC component sum is $6,207. Among ZIP codes with claim records, 24% have an A- or V-family dominant rated zone recorded in those historical claims. This is not a complete current FEMA property-map inventory.

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.

Claim count does not establish current property risk. Check the exact address in FEMA's current map and obtain a property-specific insurance quote when relevant.

Source: historical FEMA National Flood Insurance Program (NFIP) claim records. No current FEMA property-map designation is asserted.