Estuary News, October 2006

San Francisco Estuary Partnership (SFEP) | October 15th, 2006

Executive Order N-4-23

State of California | March 10th, 2023

Fundamentals of estimating the net benefits of ecosystem preservation: The case of the Salton Sea

Hydrobiologia (Springer) | July 15th, 2008

This article, both theoretical and methodological in nature, argues the potential merits of using a net benefits’ framework as a tool to aid policy-makers in their eff

This article, both theoretical and methodological in nature, argues the potential merits of using a net benefits’ framework as a tool to aid policy-makers in their efforts to compare Salton Sea restoration alternatives and inform the public as to the potential magnitude and distribution of trade-offs associated with each alternative. A net benefits approach can provide a more accurate comparison and evaluation of the potential net returns from public spending on Salton Sea restoration than what wouldbe provided under the suggested criteria of current legislative mandates. Furthermore, a net benefits framework provides a more lucid and systematic accounting framework by which to enumerate the full array of benefits and costs of each alternative for policy analysis. Finally, net benefits’ analysis serves to add transparency to the decision-making process sothat the public gains an understanding of how its scarce resources, including both financial and natural capital, are being appropriated. Additionally, we illustrate and emphasize the importance of estimating the non-market values associated with many of the ecosystem services provided by the Salton Sea and describe the major techniques that do so.

Groundwater Quality in the Shallow Aquifers of the Madera– Chowchilla and Kings Subbasins, San Joaquin Valley, California

U.S. Geological Survey (USGS) | January 8th, 2018

Groundwater Quality of the Lucerne Valley Groundwater Basin, California

U.S. Geological Survey (USGS) | July 7th, 2022

Anthropogenic activities, including groundwater withdrawals, return flow from irrigated agriculture, and treated wastewater-effluent disposal have the potential to affect

Anthropogenic activities, including groundwater withdrawals, return flow from irrigated agriculture, and treated wastewater-effluent disposal have the potential to affect groundwater quality in the Lucerne Valley groundwater basin, located in the southwest Mojave Desert. Questions regarding the current state and potential future of groundwater quality in this basin were addressed by (1) considering groundwater data from and findings of historical water-quality studies, (2) evaluating recent (1990–2021) U.S. Geological Survey water-quality and geochemical-tracer data, and (3) assessing groundwater-quality results from samples collected in 2021 to better understand the transport of applied treated wastewater effluent in the subsurface and associated effects of this practice on water quality. As observed by previous studies, differences in groundwater quality existed among the upper, middle, and lower aquifers of the Lucerne Valley groundwater basin, with the lower aquifer characterized by high dissolved-solid content relative to the middle and upper aquifers. Stable and radioisotope tracers indicate that most of the groundwater sampled in the basin was recharged during cooler, wetter climate conditions than those of the present day (2022). Analyses of the 2021 samples collected to examine the subsurface transport of applied treated wastewater effluent were not conclusive but indicate that water from applied treated wastewater effluent is currently (2022) limited to the upper aquifer and likely to remain so given the extensive confining unit below the upper aquifer.

Hazard: The Future of the Salton Sea With No Restoration Project

Pacific Institute | May 1st, 2006

The Salton Sea lies on the brink of catastrophic change. The amount of water flowing into the Sea in the next twenty years will decrease by more than 40%, causing

The Salton Sea lies on the brink of catastrophic change. The amount of water flowing into the Sea in the next twenty years will decrease by more than 40%, causing its surface elevation to drop by more than 20 feet, rapidly shrinking its volume by more than 60%, tripling its salinity, and exposing more than 100 square miles of dusty lakebed to the desert’s blowing winds. These changes will cause four major impacts: Human health in the Imperial and Coachella valleys – currently home to more than 400,000 people and growing quickly – will be harmed by the estimated 33% increase in the amount of fine windblown dust in the basin. The Imperial Valley already suffers from the highest childhood asthma hospitalization rate in the state; the growing number of retirees living in both valleys are especially susceptible to poor air quality. Air quality in these two valleys – which already fails to meet state and federal air quality standards – would get much worse, increasing the cost of bringing these areas into compliance. Air quality-related litigation and state liability will increase. California has assumed ultimate responsibility for managing only those lands exposed due to a recent set of water transfers, constituting about half of the estimated 134 square miles exposed in 30 years. Responsibility for managing any dust blowing off the other 60 or so square miles will rest with the individual property owner. However, there is no clear way to determine which lands will be exposed due to the water transfers and which will be exposed due to other actions. Total air quality management costs at Owens Lake have exceeded $400 million. Costs at the Salton Sea could be higher. Many – if not most – of the hundreds of thousands of birds that currently use the Sea will lose their roosting and breeding habitats and their sources of food. The Sea’s fish will be almost entirely gone within a dozen years. Those birds that remain will suffer from disease and the reproductive deformities and failures that plagued the Kesterson National Wildlife Refuge twenty years ago. Some of the endangered and threatened species that use the Sea may be able to find other habitats, but others could suffer significant population losses. The tremendous scale of the Sea adds to its complexity, and the difficulty of finding a viable solution. The Sea currently runs almost 35 miles long, and 15 miles at its widest point, covering about 365 square miles. It has the largest surface area of any lake in California, yet is barely 50 feet at its deepest point. The Sea is 1/3 saltier than the ocean, and, fed by the fertilizers running off of neighboring fields, sustains incredible levels of biological productivity. Until recently, the amount of water entering the Sea was roughly balanced by the amount of water evaporating from its broad surface. Stabilizing the Sea at its current salinity would require the removal of more than four million tons of salt each year, assuming flows to the Sea do not change. But they will change. Under a set of agreements signed in 2003, the Imperial Valley has begun to transfer water to San Diego County, ultimately reducing flows to the Salton Sea. Other actions, including actions in Mexico, will also reduce the amount of water flowing to the Sea, by 45% or more in the next 30-40 years. These changes will dramatically decrease the size of the Salton Sea and the quality of its water. In September, 2003, the California legislature passed a set of laws that implement the 2003 water agreements and provide a 15-year reprieve for the Sea. The legislation offers the prospect of more than $300 million of restoration funds, but it does not guarantee a long-term restoration project for the Salton Sea. California’s Resources Agency will submit a Salton Sea Ecosystem Restoration Plan and related documents to the state legislature by December 31, 2006. The cost of any long-term restoration plan will almost certainly exceed a billion dollars. Although various private-public partnerships have been suggested, funding and implementation of any restoration plan is far from certain, especially given the lack of consensus on a preferred alternative.

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.

Managing Agricultural Irrigation Drainage Water: A guide for developing Integrated On-Farm Drainage Management systems

California State Water Resources Control Board (SWRCB) | May 6th, 2004

Chronic problems of salt, selenium, boron and other naturally occurring elements in surface and groundwater supplies plague agricultural regions throughout the Westside o

Chronic problems of salt, selenium, boron and other naturally occurring elements in surface and groundwater supplies plague agricultural regions throughout the Westside of the San Joaquin Valley and the western U.S. Compounding the problem is the build-up of salty subsurface groundwater resulting from dense clay layers and inadequate natural drainage. The Integrated On-Farm Drainage Management (IFDM) system was developed to manage these problems. A state-of-the-art, yet practical irrigation management system, the IFDM provides for drainage water reuse to improve water availability for crop production and to minimize salt and selenium risks to water quality and the environment. IFDM manages irrigation water on salt sensitive, high value crops and reuses drainage water to irrigate salt-tolerant crops, trees and halophyte plants. Salt and selenium are removed from the farming system and can be marketed. This system views the subsurface drainage water containing salts and selenium as resources, rather than considering them as wastes and environmental problems.

Methods of Analysis—Determination of Pesticides in Filtered Water and Suspended Sediment using Liquid Chromatography- and Gas Chromatography-Tandem Mass Spectrometry

U.S. Geological Survey (USGS) | January 31st, 2024

The widespread application of pesticides in agricultural and urban areas leads to their presence in surface waters. Presence of these biologically active chemicals in en

The widespread application of pesticides in agricultural and urban areas leads to their presence in surface waters. Presence of these biologically active chemicals in environmental waters potentially has adverse effects on nontarget organisms. To better understand the environmental fate of these contaminants, a robust method to capture chemicals with wide-ranging physicochemical properties has been developed. The method was developed by the U.S. Geological Survey’s Organic Chemistry Research Laboratory to monitor pesticides, pesticide degradates, and other agrochemicals in environmental surface waters throughout the country. The analysis involves a multiresidue method to determine 183 pesticides and pesticide degradates in filtered water samples and 178 pesticides and pesticide degradates in paired suspended sediment samples. After the filtration of whole water, contaminants are individually measured in the filtered water and the collected suspended sediment. Filtered water is extracted via solid-phase extraction, whereas suspended sediment is extracted using an ultrasonication, solid-liquid extraction. Samples are analyzed by liquid chromatography-tandem mass spectrometry using an electrospray ionization source in positive and negative modes and analyzed by gas chromatography-tandem mass spectrometry using an advanced electron ionization source in positive mode. Instrument parameters were optimized for the highest sensitivity, and at least two transitions (quantifier and qualifier) were monitored for each analyte. Recoveries in test filtered water (n=9; 183 analytes) from the American River, California, and suspended sediment (n=9; 178 analytes) samples fortified at 15 nanograms per liter (ng/L) ranged from 70.1 to 121.0 and 71.1 to 117.0 percent in water and suspended sediment filter samples, respectively.

MSS Salinity Point Source and Ion Sampling to the Monitoring Special Study Plan CY 2022–2023 Work Plan Monitoring Plan

California Department of Water Resources (DWR) | August 16th, 2023

The interior southern Delta region of the San Francisco Estuary (SFE) has relatively higher seasonal-based salinity compared to other interior freshwater regions. Some of

The interior southern Delta region of the San Francisco Estuary (SFE) has relatively higher seasonal-based salinity compared to other interior freshwater regions. Some of this degradation in water quality in the interior southern Delta likely originates in upstream salt loading from agriculture drainage in the San Joaquin River prior to reaching the channels of Old River and Grant Line Canal. However, there is also measurable increases in salt loading within the channel networks of Old River at Head (OH1) east to lower Old River near Mountain House Creek (ORM) and the interconnected sloughs of Paradise and Sugar Cut in the region of Doughty Cut (in-Delta agriculture drainage), as well as other naturally occurring (i.e., groundwater) sources and other non-point and point sources. The California Department of Water Resources (DWR) and U.S. Bureau of Reclamation (Reclamation), under the State Water Resources Control Board’s (State Water Board) Water Right Decision 1641 (D-1641), are assigned partial responsibility for meeting interior southern Delta water quality objectives each year at multiple compliance stations that measure specific conductance (EC) data continuously at 15-minute intervals.