Water Quality Reports > Seattle WA Drinking Water Quality Report
Water Quality Score
B+
Seattle WA Drinking Water Quality
Water Quality Factors
  • Failed some Health Guidelines
  • Failed some Legal Limits
  • Met all Reporting and Monitoring Requirements
  • Uses Chlorine disinfectant

Seattle is known to have some of the cleanest tap water in the country. Seattle Public Utilities (SPU) provides the city with water from two local, protected sources - the Cedar River Watershed and the South Fork Tolt River Watershed located in the mountains around Seattle. In an effort to protect these watersheds, the city of Seattle purchased the 90,000+ acres of land around and atop the watersheds. Water is treated with chlorine, ozone and ultraviolet light to reduce contamination. Once the water leaves the treatment center, the main concern for residents is lead or copper contamination from pipes and plumbing as well as pipe breaks or leaks where contamination can enter the water supply.

Seattle, WA Drinking Water Top Suppliers

Water SupplierWater Supply SourcePopulation ServedService Connections
Seattle Public Utilities
Po Box 34018 Seattle, WA 98124-4018
Surface Water 668,800 184,030
Data Sources:
EPA 2012 SDWIS Report

Seattle, WA Water Quality Recent Violations

There were no health violations for in the 2010-2012 reporting periods

There were no reporting, montioring or other reported violations for in the 2010-2012 reporting periods

To see the latest EPA monitoring report for visit the EPA at SDWIS Report

Seattle, WA Water Quality Historical Violations

Detected
15
Above Health Limits
1
Below Limits
13
ContaminantTotal Tests Positive ResultsAbove Health LimitsAbove Legal LimitsEPA RegulatedMax ResultHealth Limit Legal Limit
Lead (total) 176 142 141 1 Yes 61.20 0.20 15
Trichloroacetic acid 12 12 1 0 Yes 27.70 20 60
Aluminum 3 3 0 0 No 41 - -
Barium (total) 3 3 0 0 Yes 1.70 2000 2000
Bromodichloromethane 14 14 0 0 Yes 4.30 100 80
Chloroform 14 14 0 0 Yes 60.20 70 80
Copper 175 174 0 0 Yes 516 1300 1300
Dibromochloromethane 14 2 0 0 Yes 0.20 60 80
Dichloroacetic acid 12 12 0 0 Yes 23.10 70 60
Manganese 3 3 0 0 No 2.70 300 -
Monochloroacetic acid 12 5 0 0 Yes 4.60 70 60
Nitrate 1 1 0 0 Yes 0.10 10 10
Nitrate & nitrite 5 5 0 0 Yes 1.00 10 10
Total haloacetic acids (HAAs) 12 12 0 0 Yes 41.80 70 60
Total trihalomethanes (TTHMs) 14 14 0 0 Yes 64.50 - 80

72 Water Contaminants were tested for in the Seattle, WA area but not found in drinking water between 2004 and 2009.

Data Source: NYTimes.com

The scores and results above reflect a summary of the historical drinking water testing results that has been documented by the EPA and other sources. The color coding of the symbols was developed by WaterFilterComparisions.com as an easy way for individuals to gauge the historical effectiveness of Seattle water suppliers in meeting legal and health regulations in providing clean drinking water. This should only be used as a guide, and WaterFilterComparisons recommends you contact Seattle water suppliers to better understand the quality of the drinking water in Seattle, .