San Joaquin River

Agricultural risks from changing snowmelt

Nature Portfolio (Springer Nature) | April 20th, 2020

Snowpack stores cold-season precipitation to meet warm-season water demand. Climate change threatens to disturb this balance by altering the fraction of precipita

Snowpack stores cold-season precipitation to meet warm-season water demand. Climate change threatens to disturb this balance by altering the fraction of precipitation falling as snow and the timing of snowmelt, which may have profound effects on food production in basins where irrigated agriculture relies heavily on snowmelt runoff. Here, we analyse global patterns of snowmelt and agricultural water uses to identify regions and crops that are most dependent on snowmelt water resources. We find hotspots primarily in high-mountain Asia (the Tibetan Plateau), Central Asia, western Russia, western US and the southern Andes. Using projections of sub-annual runoff under warming scenarios, we identify the basins most at risk from changing snowmelt patterns, where up to 40% of irrigation demand must be met by new alternative water supplies under a 4 °C warming scenario. Our results highlight basins and crops where adaptation of water management and agricultural systems may be especially critical in a changing climate.

Aliso Water District Groundwater Sustainability Plan

Aliso Water District Groundwater Sustainability Agency | January 17th, 2020

Aliso Water District Groundwater Sustainability Plan (Amended)

Aliso Water District Groundwater Sustainability Agency | July 7th, 2022

The January 2020 AWD GSA GSP, along with the other GSPs of the Delta-Mendota Subbasin, was deemed incomplete by DWR January 21, 2022 (Appendix H). The incomplete determin

The January 2020 AWD GSA GSP, along with the other GSPs of the Delta-Mendota Subbasin, was deemed incomplete by DWR January 21, 2022 (Appendix H). The incomplete determination provided 180 days to respond to the deficiencies identified by DWR. Subsequently, multiple consultations with DWR and meetings of the Delta-Mendota GSP groups were held to develop a coordinated response. This GSP, including the Common Chapter (Appendix B), addresses the concerns of DWR’s January 2022 Determination Letter. Due to size, this file has been divided. Part 1, Part 2, Part 3, Part 4, Part 5

Alternatives for Delta Water Transfers

California Department of Water Resources (DWR) | November 1st, 1983

Aluminum- and iron-based coagulation for in-situ removal of dissolved organic carbon, disinfection byproducts, mercury and other constituents from agricultural drain water

Journal of Geochemical Exploration (Elsevier) | May 9th, 2019

Agricultural production on wetland soils can be significant sources of dissolved organic carbon (DOC), disinfection byproduct precursors, mercury and nutrients to downst

Agricultural production on wetland soils can be significant sources of dissolved organic carbon (DOC), disinfection byproduct precursors, mercury and nutrients to downstream water bodies and accelerate land subsidence. Presented as a potential solution for in-situ water quality improvement and land subsidence mitigation, chemically enhanced treatment wetlands (CETWs) were used to leverage both coagulation and wetland processes. In this study, we evaluated the performance of coagulants ferric sulfate (Fe dosing) and polyaluminum chloride (Al dosing) to remove pollutants from agricultural drain water using the coagulation system designed for CETWs. Both coagulation treatments removed over 70% DOC from source waters, resulting in removal efficiencies (mg-DOC removed per mg-metal dosed) of 1 under Al dosing and 0.5 under Fe dosing. Coagulation by both treatments preferentially removed UV254 active compounds compared to the bulk DOC concentration, suggesting coagulation targeted aromatics more effectively. Phosphates and haloacetic acids were also removed more readily, whereas trihalomethanes, dissolved organic nitrogen and filtered mercury species were removed at similar or lower rates than DOC. Dissolved inorganic nitrogen was not amenable to coagulation and removal was not observed. Freundlich, Langmuir and Monod models explained 33% of the variance in DOC removal for Al dosing and 78–89% of the variance for Fe dosing. All three models indicated Al dosing had higher removal efficiency and affinity for DOC than Fe dosing under study conditions, but when used to predict maximum removal efficiency there was no cohesiveness between the three models due to different model assumptions. Consideration of fluorescence dissolved organic matter and UV254 as surrogates for DOC concentration showed both were equally suitable before coagulant application, but as surrogates after coagulant application, neither could be deemed more fit as a surrogate since both were shown suitable for different treatment scenarios.

American shad — the Delta’s most-abundant and least-considered anadromous fish

Center for California Water Resources Policy & Management | February 21st, 2022

American shad are the Chinook salmon of herring. Like Chinook salmon, adult American shad spend several years in the ocean before returning to rivers for spawning — the

American shad are the Chinook salmon of herring. Like Chinook salmon, adult American shad spend several years in the ocean before returning to rivers for spawning — they’re anadromous. Also, like salmon, anglers love shad because they’re fun to catch and good to eat. Well, okay, shad are not as good to eat as ocean caught salmon, but they are delicious when prepared well. American shad are native to the east coast of North American. They were introduced to the Sacramento River after repeated releases of shad fry — transported via the then newly completed transcontinental railroad — between 1871 and 1880. Shad quickly became abundant in the Sacramento River and proceeded to colonize many other rivers along the West Coast. In the Columbia River system, shad are now the most abundant anadromous fish species migrating upstream through impoundments on the lower Columbia River. At Bonneville Dam — 140 river miles upstream of the Columbia River mouth — an average of 2.2 million adult shad migrated upstream each year between 1992 and 2003. In contrast, an average of 940,000 adult salmonids migrated annually past Bonneville Dam during the same period.

Amoral Water Markets?

Georgetown University | June 15th, 2023

Severe water scarcity in the western United States is prompting legitimate questions about the best way to decide which places, people, industries, and species need it mo

Severe water scarcity in the western United States is prompting legitimate questions about the best way to decide which places, people, industries, and species need it most. Water markets, which allow for trading water like a commodity, are perennial proposals during times of scarcity. Water markets have an innate allure: promising to efficiently reallocate water to the highest value uses, minimize risk, and preserve the environment, while relying on the invisible hand to brush aside politically painful values-based questions. This view portrays markets as an amoral arbiter of the best use of water. But water markets are not amoral; they express the historic value judgments baked into the existing western water law system, and layering market approaches over the existing system will both exacerbate the negative impacts of those values and further entrench existing law. In this Article, we show that the West is not ready for water markets.

An Alternative Technique to Quantify the Incidental Take of Listed Anadromous Fishes at the Federal and State Water Export Facilities in the San Francisco Bay-Delta Estuary

National Marine Fisheries Service (NMFS) | July 1st, 2011

An Evaluation of Juvenile Salmonid Routing and Barrier Effectiveness, Predation, and Predatory Fishes at the Head of Old River, 2009–2012

California Department of Water Resources (DWR) | February 2nd, 2015

The California Department of Water Resources (DWR) and the U.S. Bureau of Reclamation (Reclamation) manage the State Water Project (SWP) and Central Valley Project (CVP),

The California Department of Water Resources (DWR) and the U.S. Bureau of Reclamation (Reclamation) manage the State Water Project (SWP) and Central Valley Project (CVP), respectively, and are charged to do so in a manner that maintains the survival of anadromous salmonids subject to the terms of the National Marine Fisheries Service’s (NMFS) 2009 Biological Opinion (BO) and 2011 amendments regarding the Long-Term Central Valley Project and State Water Project Operations Criteria and Plan (OCAP). Action IV.1.3 of the NMFS’s 2009 BO instructs these agencies to “consider engineering solutions to further reduce diversion of emigrating juvenile salmonids to the interior and southern Delta, and reduce exposure to CVP and SWP export facilities.” Specifically, one objective of Action IV.1.3 is to “prevent emigrating salmonids from entering channels in the south Delta (e.g., Old River, Turner Cut) that increase entrainment risk to Central Valley steelhead migrating from the San Joaquin River through the Delta.”

An Evolutionary Theory of Administrative Law

Southern Methodist University | May 25th, 2018

Law evolves to accommodate change—this is axiomatic in most academic legal traditions. But in the era of the administrative state, with congressional gridlock and a jud

Law evolves to accommodate change—this is axiomatic in most academic legal traditions. But in the era of the administrative state, with congressional gridlock and a judiciary hesitant to address policy questions, evolution of statutory law has become much more difficult. This leads to pent up demand for change in legal regimes. If the legislature and the courts cannot provide an outlet for this pressure, where does it go? How does the law continue to change? Although other scholars have looked to agencies as engines of legal change, we lack a theoretical framework to understand how that change happens. I argue that an evolutionary framework provides an informative framework for understanding administrative legal change. I provide three case studies that demonstrate the administrative evolution of the Endangered Species Act. In spite of tremendous advances in conservation, fundamental changes in scientists’ understanding of human impacts on the natural world, and increasingly strident clashes over private property rights and endangered species, the Act has remained largely unchanged for the last 35 years. In a functioning legislative system, the Act would have been amended to accommodate many of these changes. Instead, the case studies show a mechanism of legal change through agency action analogous to the mechanisms underlying biological evolution. Other commentators have argued the administrative state stymies evolution of the law, but this research contradicts that view. Applying an evolutionary framework to administrative actions creates a new theory of administrative evolution of the law, placing administrative analysis within the long tradition of evolutionary approaches to legal change used by commentators from Aristotle to Holmes. In contrast to traditional normative theories of administrative law, an evolutionary approach focuses on how change progresses over time. This theory of administrative evolution of the law also casts new light on a host of normative questions, from the role of judicial review to improvements in agency decision-making. Considering administrative actions within the broader context of the legal evolution promises a fruitful new approach to analyzing administrative law.