Based on current monitoring, Seattle holds an above-average drinking water safety record for WA - violations are infrequent and typically minor when they do appear.

Data: EPA SDWIS, FEMA NFIP, Census ACS

Water Quality in Seattle

We track home safety signals for 62 ZIP codes in Seattle, Washington. EPA community-water data is directly mapped for 36 ZIP codes and 15 water systems.

4 of 36 directly mapped ZIP records with reported violation counts (11%) have recorded EPA violations - 8 total, including 3 health-based violations.

Average Home Safety Score: A (100/100)

Water sources: Groundwater, Surface water.

Top Contaminants

Lead Risk

• Average lead level (90th percentile): 0.0017 mg/L
• 0 of 36 ZIP codes with known status exceed the EPA lead action level
• 63% of housing built before 1986 (when lead solder was banned)
• 26% of housing built before 1950 (when lead pipes were standard)
• Median year built: 1973
• Most common estimated pipe material: Galvanized Steel or Copper
• Lead exposure risk score: 51/100
• Estimated lead service line probability: 19%
• 28 ZIP codes classified as high or very high lead risk

With 63% of homes built before the 1986 lead solder ban, Seattle 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

473,864 total housing units across 62 ZIP codes:

Flood Risk

FEMA National Flood Insurance Program data for Seattle:

• 485 flood insurance claims on record
• $7,129,646 sum of reported building, contents, and ICC payment components
• 294 claims with payment data
• 191 claims without reported payment fields
• $24,250 average reported component sum among claims with payment data
• Dominant rated-zone value in historical claims: X (other)
• 7 of 32 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 62 ZIP records with zone data: Zone 3 (Low Risk)

• Zone 1 (High): 0 ZIP codes
• Zone 2 (Moderate): 0 ZIP codes
• Zone 3 (Low): 62 ZIP codes

Neighborhoods by Safety Score

Safest Areas

Areas Needing Attention

What Seattle 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 Seattle 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)

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 Seattle

• 98101 [A]
• 98102 [A]
• 98103 [A]
• 98104 [A]
• 98105 [A]
• 98106 [A]
• 98107 [A]
• 98108 [A]
• 98109 [A]
• 98111
• 98112 [A]
• 98113
• 98114
• 98115 [A]
• 98116 [A]
• 98117 [A]
• 98118 [A]
• 98119 [A]
• 98121 [A]
• 98122 [A]
• 98124
• 98125 [A]
• 98126 [A]
• 98127
• 98129
• 98131
• 98132
• 98133 [A]
• 98134 [A]
• 98136 [A]
• 98138
• 98139
• 98141
• 98144 [A]
• 98145
• 98146 [A]
• 98148 [A] - 1 violation ⚠
• 98154
• 98155 [A]
• 98158 [A]
• 98160
• 98161
• 98164
• 98165
• 98166 [A]
• 98168 [A] - 1 violation
• 98170
• 98171
• 98174
• 98175
• 98177 [A]
• 98178 [A]
• 98181
• 98185
• 98188 [A] - 3 violations ⚠
• 98189
• 98190
• 98191
• 98194
• 98195
• 98198 [A] - 3 violations ⚠
• 98199 [A]

Frequently Asked Questions

Is the tap water safe to drink in Seattle, WA?

The Home Safety Score is not a drinking-water grade. Seattle has an average score of 100/100 (grade A) across 34 ZIP codes with complete current-model evidence. Separately, there are 8 recorded EPA violations across 36 directly mapped ZIP records with reported counts, 3 of which are health-based. Check the specific ZIP and serving utility before drawing a water-safety conclusion.

Does Seattle have lead in the water?

The average 90th-percentile lead level across Seattle is 0.0017 mg/L, below the EPA action level of 0.015 mg/L. 0 of 36 ZIP codes with known action-level status exceed the EPA limit. About 63% of housing was built before 1986, when lead solder was banned.

Is Seattle at risk for flooding?

FEMA data shows 485 flood insurance claim records in Seattle ZIP codes, with an average reported building, contents, and ICC component sum of $24,250 among 294 claims with payment data. 191 claims lack reported payment fields and are not counted as zero. Among 32 ZIP codes with historical claim-zone values, 7 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 Seattle homes?

63% of Seattle housing was built before 1986, when lead solder was common in plumbing. 26% was built before 1950, when lead pipes were standard. The most common estimated pipe material is Galvanized Steel or 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 Seattle water?

The most common contaminants by violation count are Surface Water Treatment Rule, Consumer Confidence Report Rule. Across 36 ZIP codes with directly mapped EPA water data, 4 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

Cities with large shares of pre-1986 housing carry elevated aggregate risk from lead-soldered plumbing; Seattle sits on the lower end of that spectrum. The median build year of 1973 reflects a housing stock in which post-ban construction is dominant - meaning lead-soldered copper joints are less prevalent across the city as a whole. Still, aggregate figures don't tell you what's happening inside a specific older home. Any structure built before 1986, and particularly those built before 1970 when lead pipes were commonly installed, can still present meaningful lead risk regardless of the city-wide picture.

1973

Median Year Built

0%

Pre-1986 (Lead Paint Risk)

0%

Pre-1970 (Lead Pipes Risk)

Most homes in Seattle 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.

Seattle: Lead Risk & Vulnerable Populations

0.0017

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 Seattle 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.

Seattle: NFIP Claim Records and Water-Quality Context

485

Total FEMA Flood Claims

$24,250

Avg Reported Sum With Payment Data

22%

A/V Share of Claim-Record ZIPs

Historical NFIP data for Seattle contains 485 flood insurance claims. Among claims with payment data, the average reported building, contents, and ICC component sum is $24,250. Among ZIP codes with claim records, 22% 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.