Water System Information

Tustin residents and businesses receive water service from either the Tustin Water Service or the Irvine Ranch Water District (IRWD) depending on where the customer resides.  Tustin Water Services also provides water to portions of unincorporated North Tustin.  See this map for geographic service areas.  

Where does water come from?

The City of Tustin's primary source of water is groundwater pumped by nine active wells.  Communities located in north and central Orange County have an underground aquifer -- the Orange County Groundwater Basin (Basin) -- to capture and store water. This well-managed water resource reduces Orange County’s dependence on more costly imported water from Northern California and the Colorado River, helping to keep water rates reasonable and ensuring local water supply reliability.

How does water move throughout the community?

The City operates and maintains an extensive pipeline network to provide customers with high-quality drinking water.  Within the City's service area there are:

• 183 miles of main line
• 2 treatment facilities
• 7 potable water reservoirs
• 35 water quality testing stations
• 14,500+ service connections
• 2,500 fire hydrants

How do fire hydrants work?

Fire hydrants are operationally positioned throughout the pressure zones in the City’s water service area within the standards of local fire authorities. City staff inspect the hydrants in the City service area by checking their operation, flow, and pressure.

Hydrants are designed and installed during the property development process and in proximity to properties that connect to the City’s or IRWD’s water system.

In the Tustin water service area, the water flow and size of hydrants are determined by standards set by local fire authorities.  However, hydrant and water supply systems are not intended or designed to fight large scale wildfires or brush fires.

Tustin Water coordinates with the Orange County Fire Authority to prepare for fire and other emergencies. Other precautions include:

• Monitoring: Staff monitors local weather patterns and conditions that heighten risk, such as low relative humidity, strong winds, dry fuels, the possibility of lightning strikes and more. 
• Water supply: The City maintains multiple water supply sources deliberately placed throughout the City’s water service area to maintain pressure and flow during emergency situations and fire flow conditions. These sources include local groundwater wells and imported water connections through the East Orange County Water District, allowing the City to introduce alternate water supplies into the water system, boosting pressure and refilling storage reservoirs. Lastly, the City maintains emergency interconnections with neighboring agencies including the Irvine Ranch Water District, Golden State Water Company, and the City of Santa Ana.  
• Power: Permanent generators at pumping stations keep the water flowing during power outages. Portable generators can be brought in and placed at critical locations as needed during long-term power outages.
• Communication: We maintain steady communication with other agencies and first-responders to make sure hazardous conditions are addressed before problems arise.
• Public Safety Power Shutoffs: When Southern California Edison calls a Public Safety Power Shutoff (PSPS) and turns off power in high-risk areas, the City is ready to continue operating according to all actions taken above.

Please note: the information above applies to the residences and businesses within the City of Tustin’s service area.  For information about the  IRWD’s water service area, please visit the following link: IRWD Hydrant System.

How much water storage does the City have?

There are seven potable water reservoirs within the City's water service area, providing 13.8 million gallons of storage capacity.  Reservoirs are strategically placed throughout the service area to help regulate water pressure and store water.  The City also has access to water through emergency interconnections with the Irvine Ranch Water District, Golden State Water Company and the City of Santa Ana.   

What does the City do to ensure our water is clean?

Each year, over 1,500 water samples are collected throughout the water system that are analyzed by a private lab. In addition, staff monitors bulletins/notifications from State and Federal agencies to stay apprised of emerging contaminates of concern and develops mitigation measures when necessary.

For more detailed information, please visit the Water Supply & Quality webpage.