Water Quality Concerns

Do you have a question or concern about your water quality? Are you experiencing any problems with your drinking water, such as discolored water or unusual taste or odor?  The Frequently Asked Questions page may have answers to your questions. If you don’t find the answer in the FAQ and/or need additional help, please contact the Public Works Utilities and Operations Department during regular business hours 530-757-5686 or contact the non-emergency Police Department number after hours at 530-747-5400.

Water Quality Results

The City collects water quality samples on a weekly, monthly, quarterly, and annual basis depending on the constituent and sampling program. The City has over 35 dedicated sample stations around town to verify the quality of the water delivered. The City also samples the source of the drinking water in Davis consisting of 6 groundwater wells and the treated surface water prior to entering the City. Typically the City collects:

• 20 distribution system bacteriological samples weekly
• 5 distribution system hardness and boron samples monthly
• 4 distribution system disinfection by-products samples quarterly
• Numerous samples from 6 groundwater wells and 1 Point of Entry for treated surface water annually
• Residential Lead and Copper Samples Triennially

The City collects samples beyond what is required by State and Federal drinking water standards in order to better understand the quality of water being delivered. Below are links to water quality sampling results for the City of Davis. 

Hardness and Boron Monthly Sampling Results

For information on surface water testing conducted by the Regional Water Treatment Plan in Woodland (WDCWA), follow this link: WDCWA's monthly quality summary reports.

Annual Water Quality Report

The Annual Water Quality Report is required by the US Environmental Protection Agency and the State Water Resources Control Board. It is released every year in the spring and lists all constituents detected in your water supply and information about your water source, what it contains, how it compares to State and Federal standards and other related information.

View the Annual Water Quality Report

Frequently Asked Questions

One particular water quality question that customers ask the most is "What is my water hardness?" The answer is water hardness fluctuates based on the percentage of surface and groundwater provided during the year. The range of water hardness in Davis’ distribution system is typically 58 - 120 parts per million (ppm) or 3.4 - 7.0 grains per gallon (pgp). Water “Hardness” is usually the sum of naturally occurring magnesium and calcium presence in water.

Answers to More Frequently Asked Questions