For more than a decade, California has debated the merits of building tunnels to deliver water from the state’s biggest river in the north to its drought-prone regions in the south. Six thousand miles away, China has already spent tens of billions of dollars to divert water south to north.

In both regions, water is scarce and options seem thin. Supporters of dams, tunnels and canals say they are crucial to water supply; opponents argue that they imperil ecosystems, and displace communities.

But what if policy-makers could peer into the future, and get a more comprehensive look at how a planned tunnel or regulation or dam would affect both energy and water security? What if they could evaluate policies and infrastructure projects based on a holistic view of the state’s water and energy infrastructure?

Researchers at SEI are working with California agencies and Chinese institutions to do just that, using a process called Robust Decision Support (RDS) and modeling future scenarios with SEI’s Water Evaluation And Planning (WEAP) and Long-range Energy Alternatives Planning (LEAP) systems.

Lake Hodges Dam in California. Photo: Westend61 / Getty Images .

Helping policy-makers plan for a changing climate

This process can help policy-makers determine what infrastructure and policies have the best chance of success. Decisions about water and energy are interlinked; teasing out their effects on each other and on a complex web of social and environmental conditions is difficult. But researchers hope this effort will help answer tricky questions – such as how the risk of failure in one part of an energy system can lead to increased failure risks in the water system.

“By modeling water, energy and food systems, we can help policy-makers plan not only for a changing climate – where water is more scarce and weather more extreme – but also for a range of economic and demographic shifts,” said SEI Senior Scientist Annette Huber-Lee.

The effort is part of a research and development partnership between the U.S. and China called the U.S./China Clean Energy Research Center for Water-Energy Technologies, or CERC-WET. The partnership aims to help the United States and China “thrive in a future with constrained energy and water resources.” The project includes comparative studies on the water-energy nexus in Los Angeles, California, and Beijing, China.

California and China are two of the largest economies in the world. If these regions make major shifts toward sustainable water and energy, that could significantly reduce global emissions, preserve large ecosystems – and motivate other large economies to shift as well.

Recent work in California and China

In California, SEI is working with the U.S. Department of Energy and the University of California to inform planning and policy processes, specifically by modeling complex water-energy systems. In China, SEI is collaborating with Peking University (PKU) and the China Institute of Water Resources and Hydropower Research (IWHR), an organization that supports and informs water policies nationwide.

Stakeholders engaged with WET CAT give input on critical water, energy, agriculture and climate issues for the State of California. Photo: SEI.

SEI Senior Scientist Brian Joyce leads group discussion at CERC-WET workshop. Photo: SEI.

The first step is ensuring a participatory process. SEI uses Robust Decision Support, which helps stakeholders create a shared “mental model” of available opportunities and trade-offs.

To that end, SEI held a workshop last year with California’s Water-Energy Team of the Climate Action Team, a group known as WET-CAT that includes numerous state agencies including the Environmental Protection Agency, Department of Water Resources, the California Energy Commission, the Water Board, and the Air Resources Board.

The workshop, held in Sacramento, helped update and refine a model of the water, energy and food systems of California and explored what might happen if Los Angeles became more water and energy independent. Participants brainstormed on ways to make the modeling efforts more relevant for policies in each of their agencies, with ideas such as gathering more information on regional population growth and assessing the impacts of snow-driven runoff.

PKU also held workshops in China on how to adapt and apply RDS to the country’s energy and water systems. Researchers aim to understand how water and energy use in Beijing is connected, and to find efficiencies. They are exploring the energy implications of increasing reclaimed water use in Beijing, as well as assessing the energy requirements for future scenarios where climate change affects water supply.

Follow-up workshops in California and China will help refine the analyses. When complete, SEI will be able to provide policy-makers with plausible future scenarios – and with comprehensive but easy-to-use tools that show how various policies and infrastructure could increase the resilience of the energy and water sectors in the future.