UN-Water Analytical Brief on Unconventional Water Resources

United Nations (UN) | June 5th, 2020

Increasing water scarcity is recognized as a key challenge to sustainable development and major cause of conflict, social unrest and changes to traditional migration rout

Increasing water scarcity is recognized as a key challenge to sustainable development and major cause of conflict, social unrest and changes to traditional migration routes and new migration patterns. At the same time water is increasingly considered as an instrument for international cooperation to support food production, livelihoods, ecosystems, climate change adaption, and sustainable development. As water scarcity is set to continue and intensify in dry areas, the world at large is in danger of leaving the water scarcity challenge to future generations who will be confronted with the consequences of today’s practices. Thus, water-scarce areas must sustainably access and utilize every available option for water resources in order to minimize the pressure that continues to grow. Conventional water provisioning approaches relying on snowfall, rainfall and river runoff are not enough to meet growing freshwater demand in water-scarce areas. Considering the water-related sustainable development challenges in arid regions, unconventional water resources are an emerging opportunity to narrow the water demand-supply gap. There are fragmented, but growing, examples of using unconventional water resources across the world to boost water supplies to address water scarcity.

Unanswered questions for implementation of the Sustainable Groundwater Management Act

California Agriculture (UCANR) | August 24th, 2016

California is grappling with the implications of the Sustainable Groundwater Management Act (SGMA), a visionary and potentially revolutionary law that could profoundly ch

California is grappling with the implications of the Sustainable Groundwater Management Act (SGMA), a visionary and potentially revolutionary law that could profoundly change the way water is managed in the state. The nature of the revolution, however, is not yet clear. Whether and how SGMA achieves its goals hinges on open questions about its implementation.  

Uncertainty in El Niño-like warming and California precipitation changes linked by the Interdecadal Pacific Oscillation

Nature Portfolio (Springer Nature) | November 10th, 2021

Marked uncertainty in California (CA) precipitation projections challenges their use in adaptation planning in the region already experiencing severe water stress. Under

Marked uncertainty in California (CA) precipitation projections challenges their use in adaptation planning in the region already experiencing severe water stress. Under global warming, a westerly jet extension in the North Pacific analogous to the El Niño-like teleconnection has been suggested as a key mechanism for CA winter precipitation changes. However, this teleconnection has not been reconciled with the well-known El Niño-like warming response or the controversial role of internal variability in the precipitation uncertainty. Here we find that internal variability contributes > 70% and > 50% of uncertainty in the CA precipitation changes and the El Niño-like warming, respectively, based on analysis of 318 climate simulations from several multi-model and large ensembles. The Interdecadal Pacific Oscillation plays a key role in each contribution and in connecting the two via the westerly jet extension. This unifying understanding of the role of internal variability in CA precipitation provides critical guidance for reducing and communicating uncertainty to inform adaptation planning.

Undelivered Water: Fulfilling the CVPIA promise to Central Valley refuges

U.S. Bureau of Reclamation (USBR) | November 3rd, 2009

The 1992 Central Valley Project Improvement Act transformed California’s federal water management system by providing fish and wildlife a co-equal priority with other u

The 1992 Central Valley Project Improvement Act transformed California’s federal water management system by providing fish and wildlife a co-equal priority with other uses. In so doing, the Act mandated that the federal government establish a program, now known as the Refuge Water Supply Program (RWSP), to manage, secure, and deliver a reliable, clean water supply to serve the wetland habitat needs of nineteen federal, state, and private wildlife refuges in California’s Central Valley. The refuges protect a significant portion of the last remaining 5 percent of the historic Central Valley wetlands and provide birds of the Pacific Flyway habitat during critical periods when no other wetlands habitat may be available. In response to a request from OMB, the Bureau of Reclamation and the Fish and Wildlife Service established an Independent Panel to evaluate the performance of the RWSP component of the Central Valley Project Improvement Act.

Underestimating the Challenges of Avoiding a Ghastly Future

Frontiers in Conservation Science (Frontiers) | January 13th, 2021

We report three major and confronting environmental issues that have received little attention and require urgent action. First, we review the evidence that future enviro

We report three major and confronting environmental issues that have received little attention and require urgent action. First, we review the evidence that future environmental conditions will be far more dangerous than currently believed. The scale of the threats to the biosphere and all its lifeforms—including humanity—is in fact so great that it is difficult to grasp for even well-informed experts. Second, we ask what political or economic system, or leadership, is prepared to handle the predicted disasters, or even capable of such action. Third, this dire situation places an extraordinary responsibility on scientists to speak out candidly and accurately when engaging with government, business, and the public. We especially draw attention to the lack of appreciation of the enormous challenges to creating a sustainable future. The added stresses to human health, wealth, and well-being will perversely diminish our political capacity to mitigate the erosion of ecosystem services on which society depends. The science underlying these issues is strong, but awareness is weak. Without fully appreciating and broadcasting the scale of the problems and the enormity of the solutions required, society will fail to achieve even modest sustainability goals.

Understanding End-of-Century Snowpack Changes Over California’s Sierra Nevada

American Geophysical Union (AGU) | January 29th, 2019

Understanding Microplastic Levels, Pathways, and Transport in the San Francisco Bay Region

San Francisco Estuary Institute (SFEI) | October 2nd, 2019

Microplastics (particles less than 5 mm) are ubiquitous and persistent pollutants in the ocean and a pervasive and preventable threat to the health of marine ec

Microplastics (particles less than 5 mm) are ubiquitous and persistent pollutants in the ocean and a pervasive and preventable threat to the health of marine ecosystems. Microplastics come in a wide variety of shapes, sizes, and plastic types, each with unique physical and chemical properties and toxicological impacts. Understanding the magnitude of the microplastics problem and determining the highest priorities for mitigation require accurate measures of microplastic occurrence in the environment and identification of likely sources. To develop critical baseline data and inform solutions, the San Francisco Estuary Institute and the 5 Gyres Institute have completed the first comprehensive regional study of microplastic pollution in a major estuary.

Understanding the Contributions of Paleo-Informed Natural Variability and Climate Changes to Hydroclimate Extremes in the San Joaquin Valley of California

American Geophysical Union (AGU) | November 13th, 2023

Understanding the Cost of Basic Drinking Water Services in the United States: A National Assessment

American Water Works Association (AWWA) | January 23rd, 2025

The cost of basic drinking water services has implications for affordability, investment capacity, and public health. The fragmentation of drinking water services in the

The cost of basic drinking water services has implications for affordability, investment capacity, and public health. The fragmentation of drinking water services in the United States makes it difficult to reliably track and compare what customers pay for basic drinking water services. This paper uses a new, national dataset to examine the social, political, environmental, and institutional drivers of the cost of basic drinking water services, measured as the cost to households of 6000 gal of water per month. We find basic drinking water service costs vary widely across the United States. Costs are generally higher in smaller and more liberal cities and lower in places that rely on groundwater sources. Our findings provide a unique national perspective on variation in, and drivers of, the cost of basic water services and can inform efforts to improve the affordability, accessibility, and quality of drinking water services in the United States.

Understanding the recent increase in multiyear La Niñas

Nature Portfolio (Springer Nature) | September 18th, 2023