February 16, 2016

Story: Desalination and California’s water future: Experts meet to discuss knowledge gaps and ways forward

By Kristen Weiss

Inside a desalination plant. John Wiley, 2009. CC-BY-NC-2.0

In light of California’s ongoing drought and growing water needs, Stanford’s Woods Institute for the Environment, through the Center for Ocean Solutions and Water in the West, collaborated with The Nature Conservancy and the Monterey Bay Aquarium to facilitate an Uncommon Dialogue among cross-sector experts on the potential impacts of ocean desalination on coastal and marine ecosystems.

Over the course of two days, leading experts from academia, non-governmental organizations, private industry and government agencies gathered in Monterey to exchange information and promote open discussion about the best available science, technology and policy related to desalination. Meeting participants also identified key issues and knowledge gaps in science and policy that should be explored in future work. The dialogue was split into sessions that focused on the regulatory framework of desalination in California, siting and community impacts, seawater intakes and brine disposal.

Participants shared candid perspectives on a number of key issues regarding the role of desalination in California’s water future. First, participants highlighted that desalination would not, at least in the foreseeable future, significantly reduce stress on freshwater resources or ecosystems such as the Sacramento Delta. Second, desalination is likely to contribute only a small fraction to California’s total water budget due to high costs and energy requirements, although it may be very important to specific coastal communities that do not have other sources of water.

Third, in light of the limited role that desalination may play in alleviating California’s demand for potable water, the participants actively discussed how alternatives, such as water recycling and conservation, may be better utilized to relieve growing pressure on freshwater resources. Fourth, they also considered how the role of desalination might change, and potentially grow, as new technologies reduce the costs and environmental impacts associated with its use.

Fifth, although knowledge gaps persist about the various ecological and economic impacts of desalination, participants in the dialogue were encouraged by the many years of experience and data already available in California on such issues as ocean water intake and brine disposal. 

Finally, the group agreed that while most siting decisions for desalination facilities to date have been opportunistic, future desalination may require an integrated spatial approach to identify locations where facilities would best meet supply demands while also minimizing impacts to coastal and marine environments. 

Dialogue participants proposed several next steps, including drafting a white paper report summarizing the meeting, developing frameworks for synthesizing disparate datasets and linking best available science to policy for future desalination decision making. In general the group agreed that—as additional information is gathered and synthesized—a rigorous examination of the full costs, benefits and trade-offs of desalination in the context of the full costs and sustainability of current water supply solutions would also be a critically important future step.

As California’s water needs and environmental policies continue to co-evolve, there will be an ever-greater demand for integrated, innovative solutions that consider both socio-economic and environmental impacts. If experts across different sectors continue to strengthen the lines of communication opened during this two-day dialogue, the likelihood of a sustainable future for water resources in the state will greatly increase.