When it comes to predicting weather patterns in California, Forrest Gump may have said it best. “‘Life is like a box of chocolates,’ and I think this applies to California, where we experience variable hydrologic conditions, so we really don’t know what we’re going to get,” said Tiffany Tran, associate resource specialist, Metropolitan Water District of Southern California (MWD), referencing the famous movie line.
Tran kicked off the discussion “Preparing for a Parched Future” at the South Bay Cities Council of Governments (SBCCOG) 23rd General Assembly on March 23. The panel evaluated the impacts of climate change on water resources and supplies, and highlighted efforts by regional agencies and cities already preparing for those impacts.
According to Tran, historically California already has the largest year-to-year variability in precipitation in the United States. She links the more recent extreme “weather whiplash” to a global warming trend. Climate.gov statistics indicate 10 of the warmest years in the historical record have occurred since 2010. With this, California has experienced increased wildfires, rare and extreme storm events, heat waves, low snowpack and flooding.
MANAGING THE IMPACTS OF EXTREME DROUGHT
MWD is the nation’s largest wholesale water provider. It services 19 million people across six counties in Southern California and is comprised of 26 member agencies with different levels of dependence on MWD. Water sources for the region include its member agencies’ projects and programs, such as the Los Angeles Aqueduct, conservation, groundwater recycling and desalination. The remaining need is satisfied through MWD’s imported supplies from the Colorado River via the Colorado River Aqueduct, which MWD owns and operates, and from Northern California through MWD’s participation in the State Water Project, which is owned and operated by the California Department of Water Resources.
As temperatures rise, more precipitation will fall as rain instead of snow. Drier conditions will also reduce the amount of runoff that makes its way to streams, rivers and reservoirs. According to Tran, dry conditions from 2020 to 2022 in Northern California resulted in the lowest three-year combined deliveries of allocated water in the history of the State Water Project.
In addition, due to ongoing drought and increased demand for water, reservoirs on the Colorado River system, such as Lake Mead, have been shrinking since the year 2000.
“For the first time, we have drought conditions on the Colorado [River] and we have drought conditions on the State Water Project. We’re used to having one or the other, but to have both at the same time is unprecedented,” said Liz Crosson, sustainability and resilience and innovation officer, MWD.
Thanks to recent storms, conditions have improved, but MWD is asking its communities to continually review ways to take advantage of intermittent wet periods and paths to store and preserve water to manage future dry years.
SOUTH BAY WATER PROGRESS
West Basin Municipal Water District is a wholesale water agency that provides imported drinking water and recycled water to a service area of nearly 1 million people, and 17 cities and unincorporated areas in Los Angeles County. Gregory Reed, general manager, West Basin, highlighted its efforts to improve water resiliency.
More than 25 years ago, West Basin received state and federal funding to design and build the Edward C. Little Water Recycling Facility, the largest facility of its kind in the United States. In partnership with the city of Los Angeles, it delivers up to 40 million gallons of water per day to 350 different sites, conserving enough drinking water to meet the needs of 80,000 households per year. The facility also diverts 40 million gallons of treated sewage each day from being discharged into Santa Monica Bay.
Several different types of customer-specific recycled water are produced at the facility:
Irrigation Water: This water is used to maintain green spaces at local city parks, golf courses, street medians and schools.
Industrial Water: This resource is provided to refineries, such as the Chevron Nitrification Treatment Plant in El Segundo for use in fuel production and other industrial processes.
Groundwater Replenishment: Advanced treated water is used for groundwater replenishment and as a barrier against seawater intrusion, protecting local groundwater aquifers from contamination.
CITY OF TORRANCE
The city of Torrance has been successful at creating a diversified water portfolio. It includes additional groundwater resources and desalinization, according to Chuck Schaich, policy and resource specialist at Torrance Public Works.
Two new potable (drinking water that comes from surface and ground sources) wells will double groundwater production later this year as part of the North Torrance Well Field Project. It will
produce between 4,000- and 5,000 acre-feet of water per year.
Torrance, the largest city in the South Bay, has its own municipal water service. California Water Service also provides water to the city.
Torrance has a brackish (saltwater) plume in its groundwater due to overpumping in the 1930s through the early 1960s. It recently completed the Goldsworthy Groundwater Desalter expansion
in partnership with the Water Replenishment District to desalinize the brackish groundwater. It currently produces 20% of the city’s potable water, with plans for expansion of the facility in the next three years to further reduce imported water and enhance the reliability and sustainability of its water resources.
In addition, Torrance is developing a potable groundwater project. When completed the Torrance Municipal Water service area will derive approximately 75% of its water from local sources.
THE CITY OF LOMITA
The Cypress Water Production Facility (CWPF) was constructed to reduce reliance on costly imported water for Lomita’s nearly 23,000 residents located within 2 square miles, according to Ryan Smoot, city manager, city of Lomita. Imported water purchased from West Basin Municipal Water District costs the city roughly double that of treated groundwater.
At CWPF, imported surface water purchased from West Bain and treated groundwater are blended. The blended water supply provides improved water reliability while reducing the cost of water to ratepayers in the city. The mix of groundwater and imported water changes throughout the year as imported water prices fluctuate.
When in operation, CWPF is the main source of water supplied to the area of the city located north of the Pacific Coast Highway and accounts for approximately two-thirds of the total demand for
water in the community.
The city is exploring secondary/redundant well feasibility and locations to minimize dependence on external water sources. •
Watch a replay of the “Preparing for a Parched Future” presentation, along with other sessions from the 23rd General Assembly, at bit.ly/3Lwy1on.