When floods hit the road: Resilience to flood-related traffic disruption in the San Francisco Bay Area and beyond

American Association for the Advancement of Science (AAAS) | August 5th, 2020

As sea level rises, urban traffic networks in low-lying coastal areas face increasing risks of flood disruptions. Closure of flooded roads causes employee absen

As sea level rises, urban traffic networks in low-lying coastal areas face increasing risks of flood disruptions. Closure of flooded roads causes employee absences and delays, creating cascading impacts to communities. We integrate a traffic model with flood maps that represent potential combinations of storm surges, tides, seasonal cycles, inter-annual anomalies driven by large-scale climate variability such as the El Niño Southern Oscillation, and sea level rise. When identifying inundated roads, we propose corrections for potential biases arising from model integration. Our results for the San Francisco Bay Area show that employee absences are limited to the homes and workplaces within the areas of inundation, while delays propagate far inland. Communities with limited availability of alternate roads experience long delays irrespective of their proximity to the areas of inundation. We show that metric reach, a measure of road network density, is a better proxy for delays than flood exposure.

When is Groundwater Recharge a Beneficial Use of Surface Water?

University of California, Berkeley (UC Berkeley) | August 1st, 2018

Any diversion and use of surface water in California requires a water right. Today, to receive a new water right permit, an entity that wants to appropriate surface water

Any diversion and use of surface water in California requires a water right. Today, to receive a new water right permit, an entity that wants to appropriate surface water must file an application with the Board. The Board may only approve an application if it determines that the proposed use of the water is for a reasonable and beneficial purpose. Currently, there is uncertainty about whether—and, if so, under what circumstances—the Board will consider groundwater recharge to be a beneficial use of water. California law makes clear that the act of recharging groundwater, alone, is not a beneficial use of water. Instead, the specific purpose of the recharge is key.

When the River Meets the Sea

Pacific Institute | June 7th, 2019

When the water runs dry: supporting adaptive governance in transboundary river basins

Water International | February 21st, 2021

Impacts of global climate change will primarily be felt through the water cycle. Adaptation to changing conditions in transboundary basins is an important precondition to

Impacts of global climate change will primarily be felt through the water cycle. Adaptation to changing conditions in transboundary basins is an important precondition to ensure regional sustainable development and political stability. However, adaptation measures in one basin country can affect water resources and adaptation options elsewhere, therefore often requiring coordinated or joint responses by riparian countries. The paper examines the potential of climate policy instruments in strengthening adaptation to changes in transboundary river basins in North America’s Colorado River Basin and Southern Africa’s Orange-Senqu River Basin. It finds that climate policy instruments are yet rarely employed to jointly manage adaptation in shared rivers but nonetheless harbour great potential.

Where the Wild Things Aren't: Making the Delta a Better Place for Native Species

Public Policy Institute of California (PPIC) | April 5th, 2012

This report proposes a reconciliation approach for addressing 160 years of accumulated problems and for managing the Delta’s ecosystem in the future. Reconciliation eco

This report proposes a reconciliation approach for addressing 160 years of accumulated problems and for managing the Delta’s ecosystem in the future. Reconciliation ecology seeks to improve conditions for native species while recognizing that most ecosystems have been altered irrevocably by human use and will continue to be used to support human goals. Improving ecosystem conditions for native species must, therefore, happen in a context of continuing use of land and water by humans and continuing physical and biological change.

Where We Agree: Building Consensus on Solutions to California’s Urban Water Challenges

Pacific Institute | March 9th, 2016

California has a long list of unresolved and difficult water challenges, made more urgent by the severe drought that is gripping the state. As the state’s population co

California has a long list of unresolved and difficult water challenges, made more urgent by the severe drought that is gripping the state. As the state’s population continues to grow and climate changes become increasingly apparent, the pressures to identify and implement solutions to these critical challenges have only intensified. Recognizing an urgent need for serious changes in the way water is managed and used in the state, a broad array of stakeholders saw an opportunity to move beyond the traditional rancor and conflict by coming together to identify pragmatic and achievable solutions to urban water challenges. During 2015, the Pacific Institute, in partnership with the California-Nevada Section of the American Water Works Association, UC Berkeley Water Center, and UC Davis Extension’s Collaboration Center, coordinated a series of in-depth Where We Agree meetings. This unique effort provided participants opportunities to set aside differences and explore water technologies and policies that would have broad support. Together, they generated a set of practical recommendations for policymakers, municipal water managers, businesses, and community groups. “It’s time to put disagreements aside and concentrate on implementing solutions that we know work and launching innovative approaches to managing the state’s water resources,” said Pacific Institute Water Program Director Heather Cooley. “I am delighted with the progress this group made to create and advance a wide range of positive, on-the-ground solutions to California’s water crisis.”

White Wolf Subbasin Technical Report

Wheeler Ridge-Maricopa Water Storage District | March 16th, 2016

The purpose of the White Wolf Subbasin Technical Study (Study) is to support the basin boundary modification request (Request) being jointly submitted to DWR by Wheeler-R

The purpose of the White Wolf Subbasin Technical Study (Study) is to support the basin boundary modification request (Request) being jointly submitted to DWR by Wheeler-Ridge Maricopa Water Storage District (WRMWSD), Arvin-Edison Water Storage District (AEWSD), and Tejon-Castac Water District (TCWD) (collectively referred to as the Districts), in accordance with the Basin Boundary Emergency Regulations. Request is a scientific request that involves the subdivision of the Kern County Subbasin of the San Joaquin Valley Groundwater Basin (DWR Basin 5-22.14) into two separate subbasins: the Kern County Subbasin and the White Wolf Subbasin (Subbasin). As shown on Figure 1, the proposed revision divides the subbasins along the White Wolf Fault (WWF), relying upon scientific evidence that demonstrates that the WWF provides a significant impediment to groundwater flow.

Who makes decisions about California's water?

Restore the Delta | January 9th, 2023

This project collected and created data on California's water managers at the state, local and individual level to determine their race and gender. At the State level, we

This project collected and created data on California's water managers at the state, local and individual level to determine their race and gender. At the State level, we used the State Workforce Analysis to examine the race and gender of water-related state executives. At the local level, we coded about 1500 directors of water agencies for race and gender and then compared each board to the race and gender of the agency service areas. At the individual level, we coded nearly 14,000 individual rights holders for race. The results were not surprising. At every level, the people who make decisions about California's water are more white and more male than the population of California. At the local agency level, boards of directors are 86% White and 79% male. At the individual level, 91% of small named water rights holders have last names that code as White.

Who Should Be Allowed to Sell Water in California? Third-Party Issues and the Water Market

Public Policy Institute of California (PPIC) | June 13th, 2003

Although significant water trading has occurred in California since the drought of the early 1990s, many localities have restricted water transfers because of the perceiv

Although significant water trading has occurred in California since the drought of the early 1990s, many localities have restricted water transfers because of the perceived harm to other users and the local economy. In Who Should Be Allowed to Sell Water in California? Third-Party Issues and the Water Market, Ellen Hanak examines water transfers in California, local resistance to them, and various approaches to resolving water disputes. Drawing on a new database of water transfers as well as interviews with state, county, and water district officials, the report calls for water management at the local level that balances the interests of other residents and the potential gains from transfers.

Why People Adopt Climate Change Adaptation and Disaster Risk Reduction Behaviors: Integrated Model of Risk Communication and Results from Hurricanes, Floods, and Wildfires

American Meteorological Society (AMS) | November 1st, 2022

With climate change, weather and climate disaster risks are increasing. At-risk individuals can take climate adaptation and disaster risk reduction behaviors to mitigate

With climate change, weather and climate disaster risks are increasing. At-risk individuals can take climate adaptation and disaster risk reduction behaviors to mitigate and prepare for disaster risks, reduce costs from damage, and save their lives. However, previous fragmented studies have not provided an integrated model to directly compare the factors and identify factors that are most influential in at-risk community members’ behaviors. I present the Integrated Model of Risk Communication by consolidating major theories. This study uses structural equation modeling of quantitative surveys to simultaneously test the impacts of 15 factors on 15 adaptation behaviors for the two most common federally declared disasters (wildfires and hurricanes with floods) in three disaster-prone U.S. states (California, Florida, and Texas) (N = 3,468). Specifically, this study examines 15 behaviors including preparedness, nonstructural mitigation, structural mitigation, insurance purchase, and adaptation policy support. Social norms perceptions, self-efficacy, response efficacy, and resource constraints strongly affect behaviors. Response efficacy strongly affects policy support. Risk perception, knowledge, and climate change perception—commonly argued to be key drivers—are insignificant or weak. The models explain 55%–86% of the variance in adaptation behaviors. Results suggest that the focus of adaptation efforts may need to shift from risk perception and climate change perception to efficacy and social norms.