An Overview of California’s Water Challenges and Solutions
John Addison
Meeting of the Minds
By John Addison
Water is a serious issue for the cities of the world. Even in a wealthy nation like the United States, people die from toxic water in Flint Michigan, confront mega droughts 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 now only four 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 Water Recycling and Efficiency
In Southern California, the emergency is less of a threat for Orange County, than for its neighbors in LA 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, agriculture, government, and industry of the region.
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 would have previously been discharged into the Pacific Ocean and purifies with many processes that remove impurities and chemicals, then uses natural filtration of basins, microfiltration, reverse osmosis and ultraviolet light with hydrogen peroxide, and finally recharging 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 getting 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 IoT with sensors are all helping.
Large organizations have improved their water efficiency. As I toured UC Irvine, I saw some initiatives that save almost 400 million gallons of water annually - recycling waste water for landscape irrigation, replacing some lawn with water wise meadow planting, conversion of its 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 like Disneyland. Where water-intensive grazing and agriculture once required 87 percent of the region’s water, their decline has saved water.
Water-Energy Nexus
In drought-stricken California, central power plants have used as much water as the 40 million residents, including all the homeowners with swimming pools. That is now changing. Coal power plants are gone. Water-thirsty nuclear reactors have all been shut down except the two at Diablo Canyon, which are scheduled for 2024 shutdown. Some fifty old once-thru water cooled gas plants are being shuttered. All this power is being replaced with solar, wind; storage, smart grid, and software make renewables as reliable as nukes and gas plants.
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 14 states that propose to share energy include California, Oregon, Washington, Nevada, Arizona, New Mexico, Colorado, Utah, Montana, Wyoming, Idaho, North Dakota, South Dakota.
Two years ago, schools were closed and thousands evacuated from homes, escaping a 2.5 million pound per day methane leak in Aliso Canyon, in LA County. The leak took months to seal. Over its 16-year life in the atmosphere, methane traps about 100 times the heat of CO2. LA depended on the methane stored at Aliso Canyon for dozens of power plants.
Although Southern California Edison (SCE) does not own Aliso Canyon, nor have any responsibility in the leak, SCE wanted to effectively manage its use of natural gas. By 2020, California will see a number of larger once-through-water-cooled generating plants close because of regulations affecting use of ocean water for such cooling. The 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, Irvine Ranch Water District will be using an energy storage system to reduce its costs and help ease demand on the grid during peak hours. The seven megawatt (MW) and 34 megawatt-hour (MWh) storage network will utilize Tesla batteries to store power at three water treatment plants, six pumping stations, a deep water aquifer treatment plant and a groundwater desalter facility.
Desalination
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 has already 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. They are world leaders.