The Municipal Utilities Department (MUD) provides water service to residents and businesses in the North and South Stockton areas. The City operates the water utility under a permit issued by the State Water Resources Control Board, Division of Drinking Water.
On June 2, 2017, City of Stockton water utility customers in the Weston Ranch area reported brown water coming from household taps. This discoloration is due to iron and manganese present in water lines. Iron and manganese can occur when there is a sudden change in pressure in the water lines. A change in pressure recently occurred when a large water user opened and then immediately closed its water connection.
While not visually appealing, iron and manganese are not harmful. The water is safe to drink and for all other household uses. For questions, please Contact Us.
For questions about the water rate adjustment or the Proposition 218 process, please submit a Service Request through Ask Stockton.
Links to information and documents presented at Special Council Meeting:
Three easy ways to learn more about our water:
Approximately 25% of the City’s water supply originates from groundwater wells with the remaining water supply from treated surface water supplied by the Stockton East Water District (SEWD). Learn more about SEWD in External Links below.
With the completion of the Delta Water Supply Project, MUD will reduce the amount of water received from SEWD and the amount of groundwater pumped each year. This reduction improves the City’s water supply reliability and protects its groundwater resources.
Read the daily report of water pumped from the Delta and a 15-day running average.
The Delta Water Treatment Plant provides a new supplemental, high quality water supply for the Stockton Metro area – up to 30 million gallons per day (MGD).
The finished project:
Please Contact Us for public tours; for security reasons, tours are by appointment only.
The Delta Water Treatment Plant was awarded a Gold LEED for energy use, lighting, water and material use, and other sustainable strategies.
For more information on LEED (established by the U.S. Green Building Council and verified by the Green Building Certification Institute), see External Links below.
Urban Water Management Plans (UWMPs) support long-term resource planning and ensure adequate water supplies are available for current and future water demands. Every urban water supplier – that provides over 3,000 acre-feet of water annually or serves more than 3,000 or more connections – is required to assess the reliability of its water sources.
This assessment is over a 20-year planning horizon considering normal, dry, and multiple dry years. The Urban Water Management Planning Act requires the City to prepare this plan every 5 years and submit to the Department of Water Resources.
The 2010 Joint Water Recycling Facilities Planning Study is an effort between the City of Stockton and the City of Lodi to consider the feasibility of using Lodi’s treated wastewater as a recycled water source for the North Stockton area. The use of non-potable water would extend the City’s water resources, address groundwater overdraft, and re-use water that would otherwise be disposed of.
The City’s comprehensive Water Conservation Program includes:
The United States Environmental Protection Agency safeguards the quality of our water supply under the U.S. Safe Drinking Water Act of 1974. In many cases, California's standards are more stringent than federal standards.
Your water supply meets all federal and state drinking water standards. For more on water quality, read these reports:
The City's water system recently violated a drinking water standard. Although this is not an emergency, customers have a right to know what happened, what you should do, and what we are doing to correct this situation. The City issued a notice that only applies to City of Stockton Water Utility customers who live in North Stockton.
MUD regularly monitors the City Water System for drinking water contaminants. On October 14, 2015, testing results showed two locations where the water system exceeded the maximum contaminant level of 80 parts per billion for Total Trihalomethane (TTHM). This exceedance was calculated based on the Locational Running Annual Average (LRAA) collected quarterly at sampling locations over the past 12 months. The LRAA for TTHM collected at two sample locations west of Interstate 5 in northwest Stockton ranged from two to four parts per billion higher than the established standard.
Residents do not need to use an alternative water supply, such as bottled water. This is not an immediate risk. TTHMs are organic chemicals that form when disinfectants react with naturally-occurring organic matter in surface water supplies. With increased conservation this year, due to the drought, water may be holding in the City's storage and distribution system longer, giving the TTHM more time to form.
Once the TTHM levels were determined, the City took immediate action by changing water sources, modifying the treatment process, and conducting systemwide flushing. MUD anticipates resolving the problem within three months.
For additional information, please contact our water conservation toll-free number.
This City of Stockton web page last reviewed on --- 6/7/2017