Identifying Major Hydrologic Change Drivers in a Highly Managed Transboundary Endorheic Basin: Integrating Hydro-ecological Models and Time-Series Data Mining Techniques

American Geophysical Union (AGU) | August 23rd, 2022

The fragile balance of endorheic lakes in highly managed semi-arid basins with transboundary water issues has been altered by the intertwined effects of global warming an

The fragile balance of endorheic lakes in highly managed semi-arid basins with transboundary water issues has been altered by the intertwined effects of global warming and long-term water mismanagement to support agricultural and industrial demand. The alarming rate of global endorheic lakes’ depletion in recent decades necessitates formulating mitigation strategies for ecosystem restoration. However, detecting and quantifying the relative contribution of causal factors (climate variability and anthropogenic stressors) is challenging. This study developed a diagnostic multivariate framework to identify major hydrologic drivers of lake depletion in a highly managed endorheic basin with a complex water distribution system. The framework integrates the Soil and Water Assessment Tool (SWAT) simulations with time-series decomposition and clustering methods to identify the major drivers of change. This diagnostic framework was applied to the Salton Sea Transboundary Basin (SSTB), the host of the world's most impaired inland lake. The results showed signs of depletion across the SSTB since late 1998 with no significant changes in climate conditions. The time-series data mining of the SSTB water balance components indicated that decreases in lake tributary inflows (-16.4 Mm3 yr-2) in response to decline in Colorado River inflows, associated with state water transfer agreements, are causing the Salton Sea to shrink, not changes in the irrigation operation as commonly believed. The developed multivariate detection and attribution framework is useful for identifying major drivers of change in coupled natural-human systems.

Incentive-based Instruments for Freshwater Management

Pacific Institute | December 1st, 2015

This new synthesis report from the Pacific Institute and the Foundation Center provides a review of existing evidence about the use of incentive-based instruments worldwi

This new synthesis report from the Pacific Institute and the Foundation Center provides a review of existing evidence about the use of incentive-based instruments worldwide. Based on case studies, evaluations, journal articles, and white papers, the authors provide a detailed review of three incentive-based instruments: water trading, payment for ecosystem services, and water quality trading. The report and interactive tool highlight the importance of finding the right fit between a community’s water goals and the water management tool(s) it might choose and, perhaps most importantly, characterize the conditions required for their effective implementation. Originally commissioned by The Rockefeller Foundation, all of the results from this project: the synthesis report, interactive tool, and digital collection are freely available for funders, practitioners, and researchers to use, contribute to, and build on in their work.

Information for Parties Preparing Proposals for Water Transfers Requiring Department of Water Resources or Bureau of Reclamation Approval

California Department of Water Resources (DWR) | December 1st, 2015

Legal Change and Water Market Transaction Costs in Colorado

American Geophysical Union (AGU) | January 29th, 2020

Water markets are commonly described as failing to achieve efficient water management because of transaction cost barriers to trade. In the western United States, two sou

Water markets are commonly described as failing to achieve efficient water management because of transaction cost barriers to trade. In the western United States, two sources of legal conflict frequently drive transaction costs: (1) negative externalities of trading and (2) uncertain property rights. Conflicts arise because water law applies a no‐injury rule that prevents water transfers from modifying water available to third‐party water rights and defines water rights by historical water use, among other reasons. Existing literature suggests many legal changes to reduce transaction costs, but no studies in the western United States quantify transaction costs under proposed future changes. Here we developed statistical models of transaction costs for water transfer proponents under four specific legal changes in the state of Colorado. Two legal changes would modify the no‐injury rule, and two aim to clarify property rights. Colorado hosts active markets and has recently experienced debate over such legal changes. By surveying 100 legal and hydrologic experts, we elicited transaction cost estimates and rankings of which legal changes were most likely to increase third‐party injury. The legal changes that aim to clarify property rights had significantly lower likelihoods of increasing injury. One of these legal changes, which would not limit transferable water to historical use in certain circumstances, also had the greatest reductions in proponents' transaction costs. Meanwhile, the legal changes that directly modify the no‐injury rule project substantial transaction cost savings but much higher likelihoods of increased injury. The results demonstrate trade‐offs between reducing transaction costs and increasing third‐party effects.

Managed Environmental Water Use Efficiency: Evidence in Practice

University of California, Berkeley (UC Berkeley) | May 12th, 2006

The California Water Plan Update 2005 first introduced the term Managed Environmental Water Use Efficiency (MEWUE). Specifically, it defines MEWUE as a “mechanism to an

The California Water Plan Update 2005 first introduced the term Managed Environmental Water Use Efficiency (MEWUE). Specifically, it defines MEWUE as a “mechanism to analyze alternative uses of managed environmental water to determine which allocation of a given amount of water will maximize environmental benefits, and as a means to improve decision-making over time.” While MEWUE is a new term, we found several instances where managers maximized environmental benefit from a given amount of water in current practice. This paper demonstrates and analyzes current applications of MEWUE. It then provides the Department of Water Resources with the following recommendations to advance the concept and formally incorporate it into environmental water management: Formalize a MEWUE Policy to clearly state that the goal of MEWUE is a management strategy to maximize environmental benefit and not a water conservation policy. Develop Best Management Practices to increase understanding, provide guidance, and encourage use of MEWUE. Operate a MEWUE Pilot to learn more about the way MEWUE works, understand its strengths, and improve on its weaknesses. Facilitate an Environmental Water Market by applying experience and infrastructure to provide solutions for projects that require more water.

Optimization of environmental water purchases with uncertainty

American Geophysical Union (AGU) | August 5th, 2006

Water managers are turning increasingly to market solutions to meet new environmental demands for water in fully allocated systems. This paper presents a three-stage pr

Water managers are turning increasingly to market solutions to meet new environmental demands for water in fully allocated systems. This paper presents a three-stage probabilistic optimization model that identifies least cost strategies for staged seasonal water purchases for an environmental water acquisition program given hydrologic, operational, and biological uncertainties. Multistage linear programming is used to minimize the expected cost of long-term, spot, and option water purchases used to meet uncertain environmental demands. Results prescribe the location, timing, and type of optimal water purchases and illustrate how least cost strategies change as information becomes available during the year. Results also provide sensitivity analysis, including shadow values that estimate the expected cost of additional dedicated environmental water. The model’s application to California’s Environmental Water Account is presented with a discussion of its utility for planning and policy purposes. Model limitations and sensitivity analysis are discussed, as are operational and research recommendations.

Pathways and Barriers to Corporate Water Stewardship in the Colorado River Basin

Pacific Institute | October 24th, 2023

The Colorado River is the lifeblood of the American West. It supports 30 Native American tribes and farms, cities, and ecosystems in seven US states—Arizona, California

The Colorado River is the lifeblood of the American West. It supports 30 Native American tribes and farms, cities, and ecosystems in seven US states—Arizona, California, Colorado, Nevada, New Mexico, Utah, and Wyoming—and the Mexican states of Baja California and Sonora. However, the river is in crisis. Twenty-three years of drought, the over-allocation of water, and climate change have exacerbated a structural deficit—where more water leaves the system than enters it—for the tribes, communities, and ecosystems that depend on the Colorado River. To advance water resilience in the Colorado River Basin (Basin), accelerated action and investment are required from all sectors. These efforts must be strategic, coordinated, and amplified to effectively tackle the Basin’s challenges. Corporations can play a key role through their operations and supply chains, and by co-funding innovative projects. While a subset of leading companies is engaging in corporate water stewardship (CWS) in the Basin, more is needed to meet the magnitude of the water crisis at hand. This report outlines barriers and pathways to CWS in the Basin based on 20 interviews with corporate and non-corporate stakeholders from February to April 2022, and interviewee feedback on the results. The report is part of a broader Pacific Institute effort to advance CWS in the Basin. We are using these findings to prioritize CWS projects, initiatives, and approaches to pilot and scale in the Basin. More broadly, the findings are applicable to moving CWS toward building long-term water resilience in the Basin and other water-stressed basins around the world.

Quantification Settlement Agreement and Related Agreements and Documents to which Southern California Agencies are Signatories

California Natural Resources Agency (CNRA) | October 10th, 2003

Recent California Water Transfers: Implications for Water Management

Natural Resources Journal (University of New Mexico) | December 1st, 1995

The 1991 and 1992 California Drought Emergency Water Banks were the first large water transfer programs in the nation in which the State served as the predominant

The 1991 and 1992 California Drought Emergency Water Banks were the first large water transfer programs in the nation in which the State served as the predominant broker for water trades. Although the State-sponsored Water Banks have drawn widespread attention, there have been a great number of water transfers and exchanges taking place in California independently of the State. These non-State transfers illustrate well the widespread applicability of transfers in managing water resource systems, as well as the multiple mechanisms available for effecting water transfers. This paper focuses on California's recent experiences with water transfers, and offers a series of potential lessons for federal, state, and local managers for integrating water transfers in regional water resource systems.

Recent California Water Transfers: Implications for Water Management

Natural Resources Journal (University of New Mexico) | January 3rd, 1995

The 1991 and 1992 California Drought Emergency Water Banks were the first large water transfer programs in the nation in which the state served as the predominant broke

The 1991 and 1992 California Drought Emergency Water Banks were the first large water transfer programs in the nation in which the state served as the predominant broker for water trades. Although the state-sponsored Water Banks have drawn widespread attention, there have been a great number of water transfers and exchanges taking place in California independently of the state. These transfers illustrate well the widespread applicability of transfers in managing water resource systems, as well as the multiple mechanisms available for effecting water transfers. This article focuses on California's recent experiences with water transfers, and offers a series of potential lessons for federal, state, and local managers for integrating water transfers in regional water resource systems.