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Lessons from Orange County, California's water strategy

And why water is the greatest challenge in resiliency planning.

This article originally appeared on

Water is a serious issue for the cities of the world. Even in a wealthy nation such as the United States, people die from toxic water in Flint, Michigan, confront megadroughts in Los Angeles, face salinated aquifers in Miami and worry in Omaha about oil pipeline spills in the Ogallala aquifer. The American Society of Civil Engineers (ASCE) in its annual U.S. infrastructure report card gives U.S. drinking water a grade of D. Water is the greatest challenge in resiliency planning.

Southern California heavily depends on water from the Colorado River. Recent droughts have caused water levels at the Lake Mead, our nation's largest reservoir, to drop over 100 feet. Shockingly, the lake is at only 38 percent of capacity. It is only 4 feet above the legal emergency level of 1,075 feet. With droughts come more frequent and intense wildfires. For the past five years, California has experienced wildfires 12 months per year.

Orange County's focus on water recycling and efficiency

In Southern California, the emergency is less of a threat for Orange County than for its neighbors in Los Angeles County, San Diego County and Riverside Country.

In Orange County, Anaheim, Santa Ana, Irvine and other cities support regional smart water management with extensive recycling and world-leading technology for the water-energy nexus. The Orange County Water District (OCWD) plays a major role in supplying water to the 2.5 million people of the region along with agricultural, government and industry interests.

The county's groundwater replenishment system is the world's largest water purification system for indirect potable reuse.
Over 250 billion gallons of clean drinking water have been recycled. The groundwater replenishment system (GWRS) is the world's largest water purification system for indirect potable reuse. The system takes 200 million gallons daily of wastewater that previously would have been discharged into the Pacific Ocean and purifies it with many processes that remove impurities and chemicals; it then uses natural filtration of basins, microfiltration, reverse osmosis and ultraviolet light with hydrogen peroxide; and finally recharges existing groundwater. Orange County denizens drink some of the world’s cleanest water.

The groundwater basin is only 46 percent full, but that is an annual improvement thanks to reduced pumping. After years of severe drought, water conservation is achieved with carrots and sticks in Orange County. OCWD promotes drought-tolerant landscaping. Water-conserving devices and rebates are offered. People get fined for hosing off driveways or not using a shut-off nozzle when they wash their car.

Beyond centralized water recycling, water reuse is also done at the building level, following zero-energy and living-design principles. Water efficiency, AMI (advanced meters), leak detection, storage, infrastructure and the Internet of Things (IoT) with sensors are all helping.

Large organizations have improved their water efficiency. As I toured the University of California, Irvine, I saw some initiatives that save almost 400 million gallons of water annually — recycling waste water for landscape irrigation, replacing some lawns with water-wise meadow planting, conversion of the site's central plant to use reclaimed water for cooling campus buildings, smart labs and using IoT sensors to detect leaks.

Over the decades, Orange County has transitioned from cattle ranches, orange groves and crop fields to cities, campuses and entertainment destinations such as Disneyland. Where water-intensive grazing and agriculture operations once required 87 percent of the region’s water, their decline has saved water.

The water-energy nexus

In drought-stricken California, central power plants typically have used as much water as the 40 million residents, including all homeowners with swimming pools. That is changing. Coal power plants are gone. Water-thirsty nuclear reactors have been shut down except the two at Diablo Canyon, scheduled for 2024 shutdown. Some 50 old once-through water-cooled gas plants are being shuttered. All this power is being replaced with solar and wind resources; storage technology, smart grid infrastructure and software make renewables as reliable as nukes and gas plants.

Beyond centralized water recycling, water reuse is also done at the building level, following zero-energy and living-design principles.
California, Arizona and Nevada have a long history of fighting over water, especially from the Colorado River. As the Hoover Dam reaches a critical low, many western states are starting to cooperate over sharing renewable energy, reducing the need of water-thirsty central power plants. The states that propose to share energy include California, Oregon, Washington, Nevada, Arizona, New Mexico, Colorado, Utah, Montana, Wyoming, Idaho, North Dakota and South Dakota.

Two years ago, schools were closed and thousands evacuated from homes, escaping a 2.5 million-pound-per-day leak from the Southern California Gas natural gas storage tank in Aliso Canyon in Los Angeles County. The leak took months to seal. Over its 16-year life in the atmosphere, methane traps about 100 times the heat of carbon dioxide (CO2). Los Angeles depended on the methane stored at Aliso Canyon for dozens of power plants.

Southern California Edison (SCE), serving 15 million people in the LA area, acted at heroic speed by utility standards. Already challenged with the closing of its last two nuclear reactors, SCE also will close about 30 peaking gas (methane) plants.

By 2020, it also will close a number of larger once-through-water-cooled methane plants because drought has forced California to prioritize water efficiency. The massive loss of central generation is successfully being accommodated with renewables, energy-efficient building retrofits, energy pricing and cloud services that move demand off-peak, and with intelligent energy storage.

Teaming up with Advanced Microgrid Solutions, the Irvine Ranch Water District will use an energy storage system to reduce its costs and help ease demand on the grid during peak hours. The 7-MW, 34 megawatt-hour (MWh) storage network will use Tesla batteries to store power at three water treatment plants, six pumping stations, a deep water aquifer treatment plant and a groundwater desalter facility.

The desalination conundrum

A controversial 50 million-gallon-per-day desalination plant is in development in Huntington Beach. Opponents see the plant as destructive to marine life and too costly, with each gallon of water costing 2.5 times the cost of recycling. Supporters see it as critical to Orange County’s growth, an appropriate response to droughts and necessary with Hoover Dam only four feet above emergency level. Colorado already has curtailed water rights in the Yampa River in response to dam level and severe drought conditions.

With extensive water recycling, Orange County is not new to water controversy. In the face of increased fires and droughts, the region of 2.5 million is resilient with world-leading recycling, shifting to renewables and increased efficiency from all water users.

During your next trip to Disneyland or one of the country’s beaches, add a tour of the Orange County Water District operation. The team there are world leaders.

This story was updated Jan. 2 to clarify ownership of the Aliso Canyon methane facility.

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