Tap Water Quality Report

Tap water quality in Bothell, Washington

Served by SILVER LAKE WATER & SEWER DISTRICT. 65,033 residents.

Average score 67/100
Utilities 1
Population 65,033
D
67/100
Below Average
ⓘ How did we get this rating?
Quick answer

Tap water in Bothell, Washington receives a grade of D (67/100) from TapWaterSafety.org. It's served by SILVER LAKE WATER & SEWER DISTRICT. The most significant water quality concerns are: Haloacetic acids (HAA9) significantly above health guideline; Haloacetic acids (HAA5) significantly above health guideline; Total trihalomethanes (TTHMs) significantly above health guideline. Data sources: EPA SDWIS, EPA ECHO, EWG Tap Water Database.

Data sources for this grade: utilities.csv EWG Tap Water Database ⓘ How did we get this rating?

What's in Bothell's tap water

Top water quality concerns identified by the EPA and Environmental Working Group across the utility serving Bothell.

Haloacetic acids (HAA9) significantly above health guideline

Moderate concern

Haloacetic acids (HAA9) detected at 33.2 ppb, 554x above the EWG health guideline of 0.06 ppb.

Haloacetic acids (HAA5) significantly above health guideline

Moderate concern

Haloacetic acids (HAA5) detected at 31.2 ppb, 312x above the EWG health guideline of 0.1 ppb.

Total trihalomethanes (TTHMs) significantly above health guideline

Moderate concern

Total trihalomethanes (TTHMs) detected at 32.7 ppb, 218x above the EWG health guideline of 0.15 ppb.

Recommended filters for Bothell

Filters matched to the specific contaminants in Bothell's water supply.

Disclosure: TapWaterSafety earns a commission from purchases made through these links. This does not influence our scoring methodology or filter selection.

All contaminants detected in Bothell's tap water

Every contaminant identified, compared side-by-side against US EPA legal limits, the EU Drinking Water Directive (2020/2184), WHO Guidelines, and California's Public Health Goal. Why we show multiple standards →

Contaminant Detected EWG
US health-based
EPA
US legal
EU DWD
Europe
WHO
global
CA PHG
strictest US
Tested
sample year
Status
Haloacetic acids (HAA9)
Disinfection byproduct
33.2 ppb 0.06 554× over
Haloacetic acids (HAA5)
Disinfection byproduct
31.2 ppb 0.1 60.0 60 312× over
Total trihalomethanes (TTHMs)
Disinfection byproduct
32.7 ppb 0.15 80.0 100 218× over
Trichloroacetic acid
Disinfection byproduct
18.5 ppb 0.1 185× over
Chloroform
Disinfection byproduct
31.1 ppb 0.4 78× over
Dichloroacetic acid
Disinfection byproduct
11.6 ppb 0.2 58× over
Bromodichloromethane
Disinfection byproduct
1.58 ppb 0.06 26× over
Chromium (hexavalent)
Heavy metal
0.274 ppb 0.02 14× over
Chlorate
Disinfection byproduct
67.5 ppb 210.0 Below guideline
Manganese
Heavy metal
2.63 ppb 100.0 50 80 Below guideline
Monochloroacetic acid
Disinfection byproduct
1.13 ppb 53.0 Below guideline
Monobromoacetic acid
Disinfection byproduct
0.0458 ppb 25.0 Below guideline
Vanadium
Other
0.0263 ppb 21.0 Below guideline
Strontium
Radiological
0.0145 ppb 1500.0 Below guideline

All values in the unit of the detected level. Red cells indicate the detected level exceeds that standard. Some contaminants have limits in some jurisdictions but not others (shown as —). The "Tested" column shows the year each contaminant sample was collected.

Sources: US EPA, EU Drinking Water Directive 2020/2184, WHO Guidelines, California OEHHA PHGs, EWG Tap Water Database.

Treatment plant contact info

For service issues, water quality concerns, or to request a Consumer Confidence Report from SILVER LAKE WATER & SEWER DISTRICT.

General Contact

Address15205 41st Ave SE, Bothell, WA 98012

Treatment Plant

FacilityPurchased surface water

ZIP codes served

Bothell's public water systems serve the following ZIP codes: