Climate Vulnerability and Adaptation Study for California: Legal Analysis of Barriers to Adaptation for California’s Water Sector

California Energy Commission (CEC) | July 31st, 2012

This project focused on the legal and institutional framework associated with California’s water rights allocation system, and identifies changes to that framework that

This project focused on the legal and institutional framework associated with California’s water rights allocation system, and identifies changes to that framework that would facilitate adaptation to climate change. Since such changes may be difficult to accomplish, the project focused largely, but not exclusively, on changes that may be politically feasible now or in the future. There is already conflict in California over water allocation, and climate change will exacerbate that conflict by increasing demand and decreasing supply. Adaptation will be needed both to address already unavoidable impacts from historical emissions, and to address impacts from future emissions. To identify changes that would facilitate adaptation this study looked at recent legislation, policy proposals, and white papers addressing water reform; and off?the record interviews were conducted with individuals familiar with California water law. Having an accurate record of who is diverting water in California, and in what quantity, is the single most important step towards preparing for climate change, and the recommendations reflect that. For groundwater, the changes identified would (1) expand groundwater monitoring and reporting requirements, (2) expand groundwater planning requirements, and (3) require the State Board to improve groundwater management and to prevent the waste or unreasonable use of groundwater. For surface water, the changes we identify would (1) require the State Board to provide information about efficient agricultural water management practices, and streamline State Board procedures for enforcement actions for the waste and unreasonable use of water, (2) increase the enforcement of and penalties for failing to file a Statement of Water Diversion and Use and for illegal diversions, (3) require all beneficiaries of the water rights system to bear the cost of activities related to the administration of those rights, and (4) expand reporting requirements to require diverters to state what they believe their water rights to be.

Climate Warming and Water Management Adaptation for California

Climatic Change (Springer) | June 10th, 2010

The ability of California’s water supply system to adapt to long-term climatic and demographic changes is examined. Two climate warming and a historical climate

The ability of California’s water supply system to adapt to long-term climatic and demographic changes is examined. Two climate warming and a historical climate scenario are examined with population and land use estimates for the year 2100 using a statewide economic-engineering optimization model of water supply management. Methodologically, the results of this analysis indicate that for long-term climate change studies of complex systems, there is considerable value in including other major changes expected during a long-term time-frame (such as population changes), allowing the system to adapt to changes in conditions (a common feature of human societies), and representing the system in sufficient hydrologic and operational detail and breadth to allow significant adaptation. While the policy results of this study are preliminary, they point to a considerable engineering and economic ability of complex, diverse, and intertied systems to adapt to significant changes in climate and population. More specifically, California’s water supply system appears physically capable of adapting to significant changes in climate and population, albeit at a significant cost. Such adaptation would entail large changes in the operation of California’s large groundwater storage capacity, significant transfers of water among water users, and some adoption of new technologies.

Climate warming enhancement of catastrophic southern California debris flows

Nature Portfolio (Springer Nature) | June 29th, 2020

The sequence of wildfires followed by debris flows, frequently affects southern California, reflecting its drought-heavy precipitation climate bipolarity. Organic debris

The sequence of wildfires followed by debris flows, frequently affects southern California, reflecting its drought-heavy precipitation climate bipolarity. Organic debris from incomplete burning is lighter than inorganic matter, and partially inviscid. Hence lower rainfall totals can trigger downslope motion than typically required by the underlying clasts of loose inorganic granular material. After advection downslope, the pebble-laden organic debris has a higher capacity for rilling; a positive feedback process. A mechanism is proposed whereby boulders are ‘rafted’ by organic debris. This coordinated movement of boulders greatly enhances the debris flow erosion capacity. This climate change sensitive debris flow enhancing mechanism, through organic–inorganic granular material interaction, is supported by observations and the numerical simulations. Using a model explicitly parameterizing erosion processes, including runoff entrainment, rilling incision, and bank collapse, the lifecycle of the Montecito debris flow of January 9, 2018 is simulated, providing quantitative estimates of mass conveyed and debris sorting at the terminus. Peak rafting speeds are ~ 12.9 m/s at ~ 300 m asl. Total boulder (effective diameter > 25 cm) volume involved for the Ysidro Creek area alone is ~ 5 × 104 m3, scattered between the region 50–260 m asl. Debris flows are highly repeatable and locations prone to debris flows are identified and their likelihood of realization estimated.

Climate-informed hydrologic modeling and policy typology to guide managed aquifer recharge

American Association for the Advancement of Science (AAAS) | April 21st, 2021

Harvesting floodwaters to recharge depleted groundwater aquifers can simultaneously reduce flood and drought risks and enhance groundwater sustainability. However, deploy

Harvesting floodwaters to recharge depleted groundwater aquifers can simultaneously reduce flood and drought risks and enhance groundwater sustainability. However, deployment of this multibeneficial adaptation option is fundamentally constrained by how much water is available for recharge (WAFR) at present and under future climate change. Here, we develop a climate-informed and policy-relevant framework to quantify WAFR, its uncertainty, and associated policy actions. Despite robust and widespread increases in future projected WAFR in our case study of California (for 56/80% of subbasins in 2070–2099 under RCP4.5/RCP8.5), strong nonlinear interactions between diversion infrastructure and policy uncertainties constrain how much WAFR can be captured. To tap future elevated recharge potential through infrastructure expansion under deep uncertainties, we outline a novel robustness-based policy typology to identify priority areas of investment needs. Our WAFR analysis can inform effective investment decisions to adapt to future climate-fueled drought and flood risk over depleted aquifers, in California and beyond.

Co-producing actionable science for water utilities

Climate Services (Elsevier) | July 7th, 2016

This article explores the efforts of four water utilities to co-produce actionable science by forging partnerships with scientific institutions to explore integrating cl

This article explores the efforts of four water utilities to co-produce actionable science by forging partnerships with scientific institutions to explore integrating climate considerations into their specific management context. The experiences of these four utilities and their scientific partners, as part of the Piloting Utility Modeling Applications project of the Water Utility Climate Alliance, provide a wealth of empirical evidence to illustrate some of the core concepts formulated to explain how to produce usable information and how to link research to decision making. Through these four case studies of co-production, we identify three findings that bridge principles and practice: each utility engaged in contextualizing research; in building and leveraging knowledge networks; and in embracing an entrepreneurial approach to their research agenda. In several instances, unanticipated but innovative assessment techniques were developed by science partners in collaboration with water utilities to fit the utility’s specific needs. The paper concludes by discussing some of the hard realities of co-production illustrated by these cases that should be kept in mind by people contemplating similar projects.

Coastal Plain of Orange County, Basin 8-001 Alternative to a Groundwater Sustainability Plan

Orange County Water District (OCWD) | January 1st, 2017

Collaborative Versus Technocratic Policymaking: California’s Statewide Water Plan

California State University, Sacramento, (CSUS) | January 1st, 2008

In 2001, the California Department of Water Resources embarked on one of the most elaborate public involvement processes in state history. Over the course of five years a

In 2001, the California Department of Water Resources embarked on one of the most elaborate public involvement processes in state history. Over the course of five years and 200 meetings, a 65-member Stakeholder Advisory Committee and a 350-member Extended Review Forum worked with agency staff to produce a new water plan for California. The process consumed some 23,000 person-hours in face-to-face discussions alone. Although the state had been updating its water plan approximately every five years since 1957, the 2005 process produced a dramatically different type of document. For one thing, the 2005 Update is conceptually more accurate, complex, nuanced, and comprehensive. The policy recommendations described in its strategic plan address a broader range of issues—including climate change and environmental justice—yet they engendered somewhat less political controversy than the policies identified in the 1998 Update. Moreover, there is evidence that the collaborative process used in 2001-2005 catalyzed improvements in the relationships among California's historically warring water stakeholders, and also sparked the beginnings of positive cultural changes within certain quarters of DWR.This research report authored by Ariel Ambruster catalogues the outcomes of the 2005 Water Plan Update process and those of its predecessor, the 1998 Update.

Colorado River Accounting and Water Use Report: Arizona, California, and Nevada

U.S. Bureau of Reclamation (USBR) | May 15th, 2024

In accordance with Article V of the Consolidated Decree of the United States Supreme Court in Arizona v. California et al. 547 U.S. 150 (2006) (Consolidated Decree): �

In accordance with Article V of the Consolidated Decree of the United States Supreme Court in Arizona v. California et al. 547 U.S. 150 (2006) (Consolidated Decree): “The United States shall prepare and maintain, or provide for the preparation and maintenance of, and shall make available, annually and at such shorter intervals as the Secretary of the Interior shall deem necessary or advisable, for inspection by interested persons at all reasonable times and at a reasonable place or places, complete, detailed and accurate records of: (A) Releases of water through regulatory structures controlled by the United States; (B) Diversions of water from the mainstream, return flow of such water to the stream as is available for consumptive use in the United States or in satisfaction of the Mexican Treaty obligation, and consumptive use of such water. These quantities shall be stated separately as to each diverter from the mainstream, each point of diversion, and each of the States of Arizona, California and Nevada; (C) Releases of mainstream water pursuant to orders therefor but not diverted by the party ordering the same, and the quantity of such water delivered to Mexico in satisfaction of the Mexican Treaty or diverted by others in satisfaction of rights decreed herein. These quantities shall be stated separately as to each diverter from the mainstream, each point of diversion, and each of the States of Arizona, California and Nevada; (D) Deliveries to Mexico of water in satisfaction of the obligations of Part III of the Treaty of February 3, 1944, and, separately stated, water passing to Mexico in excess of treaty requirements; (E) Diversions of water from the mainstream of the Gila and San Francisco Rivers and the consumptive use of such water, for the benefit of the Gila National Forest.” This Colorado River Accounting and Water Use Report: Arizona, California, and Nevada presents the records compiled pursuant to the Consolidated Decree for Calendar Year 2023. Copies of this and previous years’ reports may be found on the Bureau of Reclamation’s website.

Colorado River Basin August 2022 24-Month Study

U.S. Bureau of Reclamation (USBR) | August 16th, 2022

Colorado River Basin Water Supply and Demand Study

U.S. Bureau of Reclamation (USBR) | December 1st, 2012

The Colorado River Basin Water Supply and Demand Study (Study), initiated in January 2010, was conducted by the Bureau of Reclamation’s (Reclamation) Upper Colorado and

The Colorado River Basin Water Supply and Demand Study (Study), initiated in January 2010, was conducted by the Bureau of Reclamation’s (Reclamation) Upper Colorado and Lower Colorado regions, and agencies representing the seven Colorado River Basin States1 (Basin States) in collaboration with stakeholders throughout the Colorado River Basin (Basin). As defined in the Plan of Study, the purpose of the Study is to define current and future imbalances in water supply and demand in the Basin and the adjacent areas of the Basin States that receive Colorado River water over the next 50 years (through 2060), and to develop and analyze adaptation and mitigation strategies to resolve those imbalances. The Study does not result in a decision as to how future imbalances will or should be addressed. Rather, the Study provides a common technical foundation that frames the range of potential imbalances that may be faced in the future and the range of solutions that may be considered to resolve those imbalances.