Groundwater Reliability Plus

About GWR Plus

EMWD’s Groundwater Reliability Plus (GWR Plus) initiative encompasses EMWD’s actions and investments to improve the quality and quantity of water in our local groundwater basins.

EMWD’s groundwater supply management has included enhancing water supplies through its recycled water program, desalination program, water use efficiency programs and, most recently, its healthy sewers program.

GWR Plus now includes a Water Banking project and our Pure Water EMWD: A Replenishment Project that combines advanced water purification and natural filtration. The Pure Water EMWD project will break ground in 2027.

To learn more download our Groundwater Reliability Plus Brochure

Groundwater

Approximately 20 percent of EMWD’s potable (drinking) water demand is supplied by EMWD groundwater wells. The majority of the groundwater produced by EMWD comes from its wells in the Hemet and San Jacinto area. Some of these wells have limited production as a result of the Fruitvale Judgment and Decree. EMWD also has wells in the Moreno Valley, Perris Valley and the City of Menifee.

Contrary to the impression of groundwater being huge underground rivers and lakes, groundwater is the water that occupies the pores and cracks in soil and rock. The source of groundwater is either natural or artificial recharge.

Natural recharge begins as rain or snow that seeps directly into the soil and rocks, or from rivers, streams and lakes. Artificial recharge is the intentional recharge of water in ponds or spreading basins; or through the use of injection wells.

Groundwater basins may be defined by geologic structures, such as earthquake faults or fault zones; or, they may be defined by administrative boundaries based on water quality or some other factor. Groundwater flow follows a path of least resistance (i.e. groundwater level gradient) to a point of equilibrium.

WaterWise Plus

Learn more about ways to stay WaterWise Plus.

Recycled Water

EMWD’s recycled water program, which is among the most robust in the nation—meeting more than one-third of EMWD’s overall water supply needs. This program is continually expanded to help further reduce the demand on groundwater supplies.

Learn more about EMWD’s Recycled Water program.

Healthy Sewers

EMWD’s Healthy Sewers Program, a public education program that promotes the responsible disposal of prescription medication and fats, oils and grease. By reducing contaminants in the wastewater collection system, EMWD can reduce treatment costs, help sustain a high-quality recycled water supply and ultimately protect future groundwater quality.

Learn more about EMWD’s Healthy Sewers program.

Desalination

In 2022, EMWD expanded its desalination program with the construction of its third groundwater desalination facility, the Perris II Desalter. This facility provides an additional 5.4 million gallons of capacity per day, enough to provide for approximately 15,000 households. This program will also further extract salt from some of EMWD’s local groundwater basins, helping to provide long-term water quality benefits.

Learn more about EMWD’s Desalination Program.

Water Banking

In 2021, EMWD completed its Mountain Avenue West Groundwater Replenishment Facility. Located in San Jacinto, it allows for water imported from northern California during wet or normal years to percolate into local aquifers and be stored for use during normal or dry years. This project improves water quality in the region and keeps groundwater basins sustainable.

Learn more about Mountain Avenue West Groundwater Replenishment Facility.

Pure Water EMWD: A Replenishment Project (Future)

In 2027, EMWD will break ground on its new Pure Water EMWD facility in San Jacinto.

This advanced water purification facility will use high-quality recycled water and further purify it using a multi-stage process of microfiltration and reverse osmosis. The purified water will be blended with additional tertiary-treated recycled water before being pumped into replenishment basins in San Jacinto.

The basins -- located at EMWD's Mountain Avenue West Groundwater Replenishment Facility -- also receive high-quality water from the State Water Project to further augment our local groundwater supplies. The purified water, mixed with the low-salinity State Water Project Water, will seep into our local aquifer, where it will go through the natural purification process underground.

State guidelines require this water to be underground for at least six months, however EMWD anticipates it will take up to five years to reach our nearest groundwater wells. The highly purified water will be pumped from deep underground and then go through one final cleaning step before it would be sent to homes and businesses.

This project will not only help provide a reliable drinking water source for our region, but improve the quality and quantity of our local groundwater basins.

Learn more about Purified Water Replenishment

Project Benefits

You never know when the next drought cycle will occur. To be better prepared for the future, we are investing in environmentally-sustainable projects that benefit our ratepayers and reduce our reliance on imported water.