UWM Plan - Municipal Water District of Orange County

Section 6
Recycled Water
IRWD’s recycled water projects, and the GWRS. GWRS uses include injection for sea
water barriers and groundwater recharge. Groundwater recharge will surpass landscape
irrigation as the greatest consumer of recycled water in Orange County. IRWD is at the
forefront of using recycled water not only for irrigation, but also for other uses such as
toilet flushing and commercial uses. Other agencies in south Orange County, such as
Moulton Niguel Water District and Santa Margarita Water District use a significant
amount of recycled water. Recycled water in Orange County is treated to various levels
dependent upon the ultimate end use and in accordance with Title 22 regulations.
OCWD Green Acres Project - The Green Acres Project (GAP) is a water recycling effort
that provides recycled water for landscape irrigation at parks, schools and golf courses as
well as for industrial uses, such as carpet dyeing.
GAP provides an alternate source of non-potable irrigation water to the cities of Fountain
Valley, Huntington Beach, Newport Beach, Santa Ana, and Mesa Consolidated Water
District. Current water users include Mile Square Park in Fountain Valley, Costa Mesa
Golf Course, Home Ranch bean field and Chroma Systems carpet dyeing. Due to a
growing demand for water in Orange County, it is sensible that recycled water be used
whenever possible for irrigation and industrial uses to supplement groundwater. The GAP
has the capacity to purify 7.5 MGD of reclaimed water from OCSD.
OCWD Groundwater Replenishment System - The GWRS, which has been operational
since January 2008, takes treated wastewater from Orange County Sanitation District and
purifies it to levels that meet state and federal drinking water standards. It uses a threestep
process that includes reverse osmosis, microfiltration and ultraviolet light and
hydrogen peroxide advanced oxidation treatment. The treated water is then injected into
the seawater barrier to help prevent seawater intrusion into the groundwater basin and is
percolated into deep aquifers where it eventually becomes part of Orange County’s
drinking water supply.
The design and construction of the GWRS was a project jointly-funded by OCWD and
OCSD. These two public agencies have worked together for more than 30 years and
began the GWRS planning in the mid-1990s. They have led the way in water recycling
and providing a locally-controlled, drought-proof and reliable supply of high-quality
water in an environmentally sensitive and economical manner.
The GWRS has a current production capacity of 70 MGD (23.5 billion gallons per year).
Once the water has been treated with the three-step process at the GWRS, treatment
facilities, approximately 35 MGD of GWRS water is pumped into injection wells where
it serves as a seawater intrusion barrier. Another 35 MGD is pumped to recharge basins
in the City of Anaheim, where GWRS water filters through sand and gravel to replenish
the deep aquifers of north and central Orange County’s groundwater basin.
Municipal Water District of Orange County
2010 Regional Urban Water Management Plan
Final
6-5