Pulse of the Delta 2011

San Francisco Estuary Institute (SFEI) | March 16th, 2011

Welcome to the first issue of the Pulse of the Delta: Monitoring and Managing Water Quality in the Sacramento – San Joaquin Delta, the new publication of the emerging D

Welcome to the first issue of the Pulse of the Delta: Monitoring and Managing Water Quality in the Sacramento – San Joaquin Delta, the new publication of the emerging Delta Regional Monitoring Program (RMP). This report is a direct response to Delta RMP stakeholders’ desire for an accessible water quality summary for the Delta that addresses important regional questions. Table of Contents: Did Contaminants Play a Role in the Pelagic Organism Decline? The Delta RMP: Re-thinking Water Quality Monitoring in the Delta Ammonia in the Delta: The science, implications for management How Delta Studies Have Reshaped Our Understanding Pyrethroid Insecticides Contaminants of Emerging Concern: Adapting to a Moving Target New Pesticides

Pulse of the Delta 2012

San Francisco Estuary Institute (SFEI) | August 2nd, 2013

This second edition of the Pulse of the Delta includes the following sections: The KEY TOPIC article introduces this year’s theme, LINKING SCIENCE AND MANAGEMENT THR

This second edition of the Pulse of the Delta includes the following sections: The KEY TOPIC article introduces this year’s theme, LINKING SCIENCE AND MANAGEMENT THROUGH REGIONAL MONITORING (PAGE 6). The MANAGEMENT UPDATE section provides updates on Delta RMP development (PAGE 12) and the U.S. Environmental Protection Agency (EPA)’s Delta Clean Water Act evaluation (PAGE 18). It further provides an update on the development of Nutrient Numeric Endpoints for San Francisco Bay, due to the relevance of this topic to Delta stakeholders (PAGE 28). And as a new feature, the Management Update section now also provides a regulatory status update for pollutants of concern. This edition of the Pulse of the Delta introduces a NEW STATUS AND TRENDS section with updates on important monitoring results (PAGE 44) and leading indicators (PAGE 50) for the Delta. The STATUS AND TRENDS section was made possible thanks to significant contributions by the Interagency Ecological Program, U.S. Geological Survey, the Central Valley Regional Water Board, California Department of Fish and Game, California Department of Water Resources, and scientists at the UC Berkeley and San Francisco State University Romberg Tiburon Center. Two FEATURE ARTICLES provide an overview of recent research findings that could help wetland managers reduce the methylmercury problem and a glimpse into the future of the Interagency Ecological Program (IEP). One of the main challenges as ecosystem restoration efforts are moving forward will be the mercury problem. Large-scale restoration of wetland areas will be required to provide a sufficient amount of aquatic habitat for restoring the Delta ecosystem. At the same time, water quality managers will need to identify actions to protect people and wildlife from exposure to methylmercury that may originate from restored wetlands, due to a legacy of mercury contamination in Delta soils. Recently completed and ongoing studies in the Yolo Bypass provide new information on management options for controlling methylmercury production in wetlands and offsite transport (PAGE 66). IEP scientists have been monitoring and researching the San Francisco Estuary since 1970. Now the IEP has arrived at an important crossroads, and its future is being decided at the same time as environmental managers are determining what a desirable future ecosystem would look like, how it would function, and how it can be established (PAGE 76).

Pumping and Ground-Water Storage Depletion in Las Vegas Valley, Nevada, 1955-1974

U.S. Geological Survey (USGS) | July 1st, 1976

Pumping for the masses: evolution of groundwater management in metropolitan Los Angeles

Geo Journal (Springer) | August 7th, 2015

Groundwater supports many aspects of human life. In cities, groundwater can provide a cost-effective source of water for drinking and industrial uses, while groundwater b

Groundwater supports many aspects of human life. In cities, groundwater can provide a cost-effective source of water for drinking and industrial uses, while groundwater basins provide storage. The role of groundwater in a city’s water supply tends to change over time. In the Los Angeles metropolitan area, groundwater is critical. Over decades, users in the region’s many basins allocated annual pumping rights to groundwater among users through adjudications. These rights were determined through collective processes over decades, which contributed to the complex array of public and private organizations involved in water management. The rights also continue to evolve. We analyzed changes in the distribution of groundwater rights over time for adjudicated basins in Southern Los Angeles County. Results indicate that groundwater rights are increasingly: (1) controlled or regulated by public institutions and municipalities, and (2) consolidated among larger users. Yet, both the percentage of total supplies provided by groundwater, as well as the distribution of groundwater rights, varies widely among cities and communities throughout Los Angeles. As metropolitan Los Angeles faces reduced water imports and emphasizes local water reliance, access to pumping rights and storage capacity in groundwater basins will become even more vital. We discuss implications of our results for future urban water management.

Punctuated Sediment Discharge during Early Pliocene Birth of the Colorado River: Evidence from Regional Stratigraphy, Sedimentology, and Paleontology

Sedimentary Geology (Elsevier) | January 1st, 2018

The Colorado River in the southwestern U.S. provides an excellent natural laboratory for studying the origins of a continent-scale river system, because deposits th

The Colorado River in the southwestern U.S. provides an excellent natural laboratory for studying the origins of a continent-scale river system, because deposits that formed prior to and during river initiation are well exposed in the lower river valley and nearby basinal sink. This paper presents a synthesis of regional stratigraphy, sedimentology, and micropaleontology from the southern Bouse Formation and similar-age deposits in the western Salton Trough, which we use to interpret processes that controlled the birth and early evolution of the Colorado River. The southern Bouse Formation is divided into three laterally persistent members: basal carbonate, siliciclastic, and upper bioclastic members. Basal carbonate accumulated in a tide-dominated marine embayment during a rise of relative sea level between ~ 6.3 and 5.4 Ma, prior to arrival of the Colorado River. The transition to green claystone records initial rapid influx of river water and its distal clay wash load into the subtidal marine embayment at ~ 5.4–5.3 Ma. This was followed by rapid southward progradation of the Colorado River delta, establishment of the earliest through-flowing river, and deposition of river-derived turbidites in the western Salton Trough (Wind Caves paleocanyon) between ~ 5.3 and 5.1 Ma. Early delta progradation was followed by regional shut-down of river sand output between ~ 5.1 and 4.8 Ma that resulted in deposition of marine clay in the Salton Trough, retreat of the delta, and re-flooding of the lower river valley by shallow marine water that deposited the Bouse upper bioclastic member. Resumption of sediment discharge at ~ 4.8 Ma drove massive progradation of fluvial-deltaic deposits back down the river valley into the northern Gulf and Salton Trough. These results provide evidence for a discontinuous, start-stop-start history of sand output during initiation of the Colorado River that is not predicted by existing models for this system. The underlying controls on punctuated sediment discharge are assessed by comparing the depositional chronology to the record of global sea-level change. The lower Colorado River Valley and Salton Trough experienced marine transgression during a gradual fall in global sea level between ~ 6.3 and 5.5 Ma, implicating tectonic subsidence as the main driver of latest Miocene relative sea-level rise. A major fall of global sea level at 5.3 Ma outpaced subsidence and drove regional delta progradation, earliest flushing of Colorado River sand into the northern Gulf of California, and erosion of Bouse basal carbonate and siliciclastic members. The lower Colorado River valley was re-flooded by shallow marine waters during smaller changes in global sea level ~ 5.1–4.8 Ma, after the river first ran through it, which requires a mechanism to stop delivery of sand to the lower river valley. We propose that tectonically controlled subsidence along the lower Colorado River, upstream of the southern Bouse study area, temporarily trapped sediment and stopped delivery of sand to the lower river valley and northern Gulf of California for ~ 200–300 kyr. Massive progradation of the fluvial-deltaic system back down the river valley into the Salton Trough starting ~ 4.8–4.5 Ma apparently was driven by a huge increase in sediment discharge that overwhelmed the sediment-storage capacity of sub-basins along the lower river corridor and established the fully integrated river channel network.

Pure Water Soquel Groundwater Model Simulation Results

Soquel Creek Water District | June 22nd, 2018

This technical memorandum discusses model simulation groundwater levels, groundwater budget, and particle tracking results to support the Environmental Impact Rep

This technical memorandum discusses model simulation groundwater levels, groundwater budget, and particle tracking results to support the Environmental Impact Report of the Pure Water Soquel project involving replenishment of advanced purified recycled water within Soquel Creek Water District’s (SqCWD’s) service area. Six model simulations have been run using the calibrated GSFLOW model for the Santa Cruz Mid- County Basin (the Basin) where SqCWD’s service area is located. These simulations have different pumping and active replenishment distributions, as follows: Two Projected Existing Conditions (No Project) simulations with SqCWD’spumping distribution reflecting future demand without additional replenishment at proposed recharge wells. Two Project simulations with SqCWD’s pumping distribution reflecting future demand and pumping re-distribution with the addition of replenishment at the Monterey and Cabrillo College Dr. sites (referred to as the Cabrillo-Monterey simulations). These simulations also represent potential replenishment at the Twin Lakes Church site instead of one of the two Cabrillo College Dr. sites. The Twin Lakes Church site is approximately 500-750 feet to the west of the Cabrillo College Dr. sites. Two Project simulations with the same pumping distribution as the Cabrillo- Monterey simulations, but with replenishment at the Monterey and Willowbrook sites (referred to as the Monterey-Willowbrook simulations).Simulation groundwater levels are evaluated for the following effects: Comparison of groundwater levels at coastal monitoring wells to protective elevations estimated to prevent seawater intrusion from further occurring in groundwater supply aquifers. Groundwater levels in the recharge wells to assess whether model results are consistent with estimated capacities for the well, recognizing that site specific testing will be needed to confirm recharge well capacities. Groundwater levels at nearby wells to evaluate effects on operation of those municipal, private, and institutional wells.Simulation groundwater budgets are evaluated for following effects: • Flows entering and leaving the Basin, including flows to and from groundwater in storage and flows offshore to prevent seawater intrusion. • Flows between groundwater and surface water. This memo does not include results for a Cumulative simulation. Information from the City of Santa Cruz to define its Aquifer Storage and Recovery project to be cumulative with Pure Water Soquel is not available or developed at this time. This memo includes results from particle tracking based on the above simulations performed to support the Salt and Nutrient Anti-degradation Study and permitting of the recharge wells. This involves particle tracking of simulated purified, replenishment water to evaluate the fate of the water as it travels in subsurface aquifers. Particle tracking is also used to evaluate travel times of purified, replenishment water, which requires refined analysis near the recharge wells. A scope to superimpose analytic element solutions for recharge and nearby extraction wells onto GSFLOW results to facilitate travel time calculations was approved by SqCWD Board December 18, 2017 and results should be forthcoming in July 2018.

Pure Water Southern California

Metropolitan Water District of Southern California (MWD) | March 29th, 2024

Pure Water Southern California Volume 1 - Draft Enviornmental Impact Report

Metropolitan Water District of Southern California (MWD) | May 14th, 2025

Pure Water Southern California (Pure Water) is a proposed partnership between The Metropolitan Water District of Southern California (Metropolitan) and the Los Angeles Co

Pure Water Southern California (Pure Water) is a proposed partnership between The Metropolitan Water District of Southern California (Metropolitan) and the Los Angeles County Sanitation Districts (Sanitation Districts) to beneficially reuse cleaned wastewater that is currently being discharged to the Pacific Ocean from the Sanitation Districts’ A.K. Warren Water Resource Facility (Warren Facility) in the City of Carson. At full buildout, Pure Water would purify up to 150 million gallons per day (MGD), making it one of the largest programs of its kind in the world. Implementation of Pure Water would provide regional benefits to all Metropolitan member agencies by: (1) reducing reliance on imported water; (2) diversifying locally available supplies; (3) improving resilience to climate change and other stressors; and (4) enhancing operational reliability and flexibility.  This Environmental Impact Report (EIR) assesses the potential environmental effects of Pure Water and was prepared in accordance with the California Environmental Quality Act (CEQA) and its implementing guidelines. Metropolitan is serving as the lead agency in preparation of this EIR; the Sanitation Districts are serving as a responsible agency. The EIR is intended to inform governmental decisionmakers and the public about the potential environmental impacts associated with construction and operation of Pure Water, and to identify ways that potentially significant impacts can be avoided or reduced by making changes to the program, selecting an alternative, and/or adopting feasible mitigation measures.  Click here for appendices.

Putting Adaptive Management into Practice: Incorporating Quantitative Metrics into Sustainable Groundwater Management

Stanford University | March 4th, 2019

Groundwater is a critical resource in California, serving as a reserve during droughts that are expected to be increasingly frequent and severe as climate change progres

Groundwater is a critical resource in California, serving as a reserve during droughts that are expected to be increasingly frequent and severe as climate change progresses. Adaptive management – revising management practices based on monitoring of progress toward pre-established quantitative metrics of performance – is widely viewed as an effective approach to managing water and other natural resources under conditions of uncertainty. However, linking performance metrics effectively with decision-making processes is often challenging, requiring careful consideration of institutional factors that may limit an agency’s ability to act based on new information. Governance arrangements that enable adaptive management must balance the need for flexibility as conditions change with a preference among water users for stable rules. The Sustainable Groundwater Management Act (SGMA) of 2014 – California’s first statewide framework for managing groundwater – incorporates many elements of adaptive management, including requirements to manage groundwater according to quantitative metrics of performance. Under regulations guiding the development of Groundwater Sustainability Plans (GSPs), newly formed Groundwater Sustainability Agencies (GSAs) must define measurable objectives, minimum thresholds and interim milestones to eliminate six “undesirable results” by 2040 or 2042, depending upon the basin. Yet, the creation of these metrics alone will be insufficient to achieve sustainable management of California’s groundwater; institutional arrangements must support their use to guide management actions. To provide insight into the design and use of metrics as guides to decision-making, this report draws upon the experiences of four special act districts that had authority to manage groundwater prior to SGMA. These include two primarily urban water agencies, Santa Clara Valley Water District (SCVWD) and Zone 7 Water Agency (Zone 7) and two agencies with significant pumping for agricultural use, Fox Canyon Groundwater Management Agency (FCGMA) and Pajaro Valley Water Management Agency (PVWMA). This report analyzes how these agencies used quantitative metrics in their groundwater management plans prior to SGMA and identifies institutional factors that constrained or enabled the adjustment of management actions in response to changing conditions during the 2012-2016 drought. Although the metrics employed by these agencies differ from those required under GSP regulations, these agencies’ experiences still offer important insights for GSAs seeking to develop metrics and integrate them into decision making.

Putting People over Fish: Stopping Radical Environmentalism to Provide Water to Southern California

The White House | January 20th, 2025