Water System


Background and History

The City of Redlands was incorporated in 1888 and developed from its origin as an agricultural area. The current population of Redlands is approximately 75,000. The City of Redlands has provided water service to the Redlands and Mentone area for more than 90 years. The Redlands water systems have grown from an untreated river supply and a few thousand feet of pipeline to the current modern and complex operation.

Redlands’ average daily water consumption is 27 million gallons per day (mgd) with a maximum daily of 50 mgd in the summer. The 2020 average Residential Gallons Per Capita daily consumption  is approximately 170 gallons per day.

The City of Redlands Municipal Utilities Department operates and maintains a water distribution system with nearly 400 miles of pipeline and 7 different pressure zones. The system has a 54.5 million gallon maximum storage capacity.

Existing Water System

Redlands receives its water from the following: 

  • Mill Creek Watershed: Water from the Mill Creek watershed is treated at the Henry Tate (Tate) Water Treatment Plant (WTP) located on Highway 38 east of Mentone.
  • Santa Ana River Watershed: Water from the Santa Ana River watershed is treated at the Hinckley WTP located north of Mentone.
  • Local Groundwater: Local groundwater is pumped from wells in Redlands, Mentone, and Yucaipa.
  • California State Water Project (SWP) Water: When required, SWP water is treated at the Hinckley WTP and Tate WTP.

Mill Creek Watershed

Mill Creek is subject to varying conditions such as rainfall and construction activity which occasionally create increased turbidity in the creek water. The turbidity of the stream water in dry weather is normally quite low.

Santa Ana River Watershed

The Santa Ana River originates in the San Bernardino Mountains, approximately 15 miles northeast of Redlands. The 35-mile-long upper portion of the Santa Ana drainage basin is bounded by Mill Creek Canyon on the east and North Fork Creek on the west. The drainage basin is one of the largest in the San Bernardino Mountains, covering more than 200 square miles. The drainage basin includes Big Bear Lake, which has a significant impact on the river’s flow and water quality. In its lower reaches, the Santa Ana becomes one of Southern California’s most prominent rivers, and eventually empties into the Pacific Ocean near Costa Mesa.

Local Groundwater

The City of Redlands owns 15 domestic wells that pump directly into the system or into reservoirs. All of these wells are adequately separated from sewerage facilities. All wells are free from serious flooding hazard. The City also receives water from two wells that are owned by the South Mountain Water Company. These wells are adequately separated from sewerage facilities.

Treatment Facilities

The Tate WTP’s primary raw water source is Mill Creek. The Tate WTP is a conventional water treatment plant built in 1967. The Tate WTP treats water with two contact clarification type clarifiers, which provide flocculation and sedimentation treatment, and four dual media gravity filters. The design capacity of the plant is 20 mgd. The City has added enhancements to the Tate WTP that provide more water supply reliability by allowing State Water Project water to be mixed with Mill Creek water for treatment.

Distribution System

Existing water transmission and distribution pipelines in the system range in size from 1 to 36 inches in diameter. There are approximately 400 miles of pipeline and 21,500 metered connections that serve domestic water.

The City of Redlands’ service area varies in elevation from approximately 1,100 to 2,600 feet above sea level. This large range of elevations requires a total of seven major pressure zones and two sub-zones to adequately serve all consumers with reasonable water pressures.

Emergency Contingencies

The City of Redlands has developed a water quality emergency notification plan for the service area. The plan outlines the procedures for notifying water users in case of imminent danger to the health of water users from some system failure. Immediate and secondary actions that must be taken are described for both a system-wide problem and a localized, isolated emergency.

Water Stock

Click here for information on water stock.