Your water met or exceeded all state and federal drinking water health standards

This report provides a snapshot of last year's water quality. EWEB is proud to say that we have never violated a maximum contaminant level or any other water quality standard established by the EPA. Learn more about EWEB's drinking water monitoring program. 

The following regulated contaminants were detected in the water. Review the comprehensive list of all the contaminants that EWEB tested for in 2021.  


Test MCL MCLG Detection Range Probable Source In Compliance?
Barium (ppm) 2 2 ND - 0.003 Erosion of natural deposits Yes
Fluoride (ppm) 4 4 ND - 0.057 Erosion of natural deposits Yes
Nitrate 10 10 ND - 0.17 Fertilizer runoff; septic leaching erosion of natural deposits Yes

Disinfection Byproducts

Test MCL MCLG Detection Range Probable Source In Compliance?
Total Trihalomethanes (ppb) 80 NA

3.7 - 8.9

Highest LRAA: 14.5

Byproduct of drinking water disinfection  Yes
Haloacetic Acids 60 NA Highest LRAA: 7.1 By product of drinking water disinfection Yes
Chlorine (ppm) 4 4 0.10 - 0.74 Added to control microbes Yes
Total Organic Carbon TT NS 0.33 - 0.49 Naturally present in the environment Yes


Test MCL MCLG Detection Range Probable Source In Compliance?
Turbidity (NTU) TT<0.3 95% of the time NA Highest result: 0.056 Soil runoff Yes

Copper and lead sampling results

The state requires EWEB to collect samples from 50 high-risk residential water taps once every three years. The following table represents our most recent testing results from 2021.

Contaminant Action Level MCLG 90th Percentile Result Samples Exceeding Action Level Source of Contaminant
Copper (ppm) 1.3 1.3 0.065 0 Corrosion of the household plumbing systems
Lead (ppb) 15 0 2.8 0

Learn more about lead and how it could get into your drinking water.

Notes on EWEB detected contaminants

The following provides additional information about the contaminants that were detected:


EWEB adds chlorine to our water during the disinfection process to protect against microorganisms such as Giardia and E.coli.


Copper is found in natural deposits and is also widely used in household plumbing materials


Turbidity is a meausre of the cloudiness of water. It can interfere with disinfection. EWEB's filtration process effectively removes turbidity.


These naturally occuring substances, found in the mineral composition of our watershed, were detected at extremely low levels - well below regulatory standards.

Total Organic Carbon

A measure of naturally-occuring organic materials in water.

Disinfection Byproducts (DBPs)

Disinfectants are an essential element in drinking water treatment because of the barrier they provide against waterborne disease-causing microorganisms. DBPs form when disinfectants used to treat drinking water react with naturally-occuring materials in the water (e.g., decomposing plant and other organic material).


Nitrate is an essential component of living things and occurs naturally in surface and groundwater at concentrations up to 1-2 mg/L. At these naturally-occuring levels, nitrate is not harmful to health.

Definitions and abbreviations

Action Level (AL)

The concentration of a contaminant which, if exceeded, triggers treatment




Parts Per Million. One part per million corresponds to one penny in $10,000 or approximately one minute in two years.

Highest Locational Running Average (LRAA)

The highest calculated average of multiple results at a single location in a 12-month period.


Contaminant not detectable using current monitoring equipment or methods.

Treatment Technique (TT)

A required process intended to reduce the level of a contaminant in drinking water.

Maximum Contaminant Level (MCL)

The highest level of a contaminant that is allowed in drinking water. MCLs are set as close to the MCLG as feasible using the best available treatment technology.

Nephelometric Turbidity Units (NTU)

A measure of water clarity.