Surveillance and Monitoring Program (SAMP) Revised Final Report

Central Valley Salinity Alternatives for Long-Term Sustainability (CV-SALTS) | December 1st, 2016

Among other things, the State Recycled Water Policy (SRWP) requires that development of the Salt and Nitrate Management Plan (SNMP) include the following element (S

Among other things, the State Recycled Water Policy (SRWP) requires that development of the Salt and Nitrate Management Plan (SNMP) include the following element (SRWP Section 6.b.3 (a)): “A basin/sub‐basin wide monitoring plan that includes an appropriate network of monitoring locations. The scale of the basin/subbasin monitoring plan is dependent upon the sitespecific conditions and shall be adequate to provide a reasonable, cost‐effective means of determining whether the concentrations of salt, nutrients, and other constituents of concern as identified in the salt and nutrient plans are consistent with applicable water quality objectives.” Furthermore, “Salts, nutrients, and the constituents identified in paragraph 6(b)(1)(f) shall be monitored. The frequency of monitoring shall be determined in the salt/nutrient management plan and approved by the Regional Water Board pursuant to paragraph 6(b)(2).” This report describes the CV‐SALTS Surveillance and Monitoring Program (SAMP), which was developed to meet the monitoring requirements of the SRWP.

Sustainability of irrigated agriculture in the San Joaquin Valley, California

National Academy of Sciences (NAS) | October 25th, 2005

The sustainability of irrigated agriculture in many arid and semiarid areas of the world is at risk because of a combination of several interrelated factors, including

The sustainability of irrigated agriculture in many arid and semiarid areas of the world is at risk because of a combination of several interrelated factors, including lack of fresh water, lack of drainage, the presence of high water tables, and salinization of soil and groundwater resources. Nowhere in the United States are these issues more apparent than in the San Joaquin Valley of California. A solid understanding of salinization processes at regional spatial and decadal time scales is required to evaluate the sustainability of irrigated agriculture. A hydro-salinity model was developed to integrate subsurface hydrology with reactive salt transport for a 1,400-km2 study area in the San Joaquin Valley. The model was used to reconstruct historical changes in salt storage by irrigated agriculture over the past 60 years. We show that patterns in soil and groundwater salinity were caused by spatial variations in soil hydrology, the change from local groundwater to snowmelt water as the main irrigation water supply, and by occasional droughts. Gypsum dissolution was a critical component of the regional salt balance. Although results show that the total salt input and output were about equal for the past 20 years, the model also predicts salinization of the deeper aquifers, thereby questioning the sustainability of irrigated agriculture.

Synergies between climate anomalies and hydrological modifications facilitate estuarine biotic invasions

Ecology Letters (Wiley) | June 6th, 2011

Environmental perturbation, climate change and international commerce are important drivers for biological invasions. Climate anomalies can further increase levels of hab

Environmental perturbation, climate change and international commerce are important drivers for biological invasions. Climate anomalies can further increase levels of habitat disturbance and act synergistically to elevate invasion risk. Herein, we use a historical data set from the upper San Francisco Estuary to provide the first empirical evidence for facilitation of invasions by climate extremes. Invasive zooplankton species did not become established in this estuary until the 1970s when increasing propagule pressure from Asia coincided with extended drought periods. Hydrological management exacerbated the effects of post‐1960 droughts and reduced freshwater inflow even further, increasing drought severity and allowing unusually extreme salinity intrusions. Native zooplankton experienced unprecedented conditions of high salinity and intensified benthic grazing, and life history attributes of invasive zooplankton were advantageous enough during droughts to outcompete native species and colonise the system. Extreme climatic events can therefore act synergistically with environmental perturbation to facilitate the establishment of invasive species.

Synthesis of Studies in the Fall Low-Salinity Zone of the San Francisco Estuary, September–December 2011

U.S. Geological Survey (USGS) | July 14th, 2014

In fall 2011, a large-scale investigation (fall low-salinity habitat investigation) was implemented by the Bureau of Reclamation in cooperation with the Interagency Ecolo

In fall 2011, a large-scale investigation (fall low-salinity habitat investigation) was implemented by the Bureau of Reclamation in cooperation with the Interagency Ecological Program to explore hypotheses about the ecological role of low-salinity habitat in the San Francisco Estuary—specifically, hypotheses about the importance of fall low-salinity habitat to the biology of delta smelt Hypomesus transpacificus, a species endemic to the San Francisco Estuary and listed as threatened or endangered under federal and state endangered species legislation. The Interagency Ecological Program is a consortium of 10 agencies that work together to develop a better understanding of the ecology of the Estuary and the effects of the State Water Project and Federal Central Valley Project operations on the physical, chemical, and biological conditions of the San Francisco Estuary. The fall low-salinity habitat investigation constitutes one of the actions stipulated in the Reasonable and Prudent Alternative issued with the 2008 Biological Opinion of the U.S. Fish and Wildlife Service, which called for adaptive management of fall Sacramento-San Joaquin Delta outflow following “wet” and “above normal” water years to alleviate jeopardy to delta smelt and adverse modification of delta smelt critical habitat. The basic hypothesis of the adaptive management of fall low-salinity habitat is that greater outflows move the low-salinity zone (salinity 1–6), an important component of delta smelt habitat, westward and that moving the low-salinity zone westward of its position in the fall of recent years will benefit delta smelt, although the specific mechanisms providing such benefit are uncertain. An adaptive management plan was prepared to guide implementation of the adaptive management of fall low-salinity habitat and to reduce uncertainty. This report has three major objectives: •To provide a summary of the results from the first year of coordinated fall low-salinity habitat studies and monitoring. •To provide a synthesis of the results of the fall low-salinity habitat studies and other ongoing research and monitoring, to determine if the available information supports the hypotheses behind the adaptive management of fall low-salinity habitat as set forth in the adaptive management plan. •To begin to put the results from the fall low-salinity habitat studies into context within the larger body of knowledge regarding the San Francisco Estuary and, in particular, the upper San Francisco Estuary, including the Sacramento-San Joaquin Delta, Suisun Bay, and associated embayments.

Talbert Seawater Intrusion Barrier Operations & Maintenance Manual

Orange County Water District (OCWD) | March 15th, 2023

OCWD’s Talbert Seawater Barrier (Talbert Barrier, Barrier) has been in operation since 1976. Since 1976 the Barrier has undergone many changes including new well design

OCWD’s Talbert Seawater Barrier (Talbert Barrier, Barrier) has been in operation since 1976. Since 1976 the Barrier has undergone many changes including new well designs and improved injection water quality. Since 2008, the Talbert Barrier has been injecting advanced treated wastewater from OCWD’s GWRS treatment plant. This manual will examine in detail the various types of injection wells, their operational procedures and the procedures followed to monitor the quality of the injection water and evaluate injection well performance. Due to size, this document has been divided. Part 1, Part 2

Technical Report on Barriers: A part of the comprehensive survey of San Francisco Bay and tributaries, California

U.S. Army Corps of Engineers (USACE) | March 15th, 1963

Technical Report on the Scientific Basis for Alternative San Joaquin River Flow and Southern Delta Salinity Objectives

California State Water Resources Control Board (SWRCB) | February 15th, 2012

The State Water Resources Control Board (State Water Board) is in the process of reviewing the San Joaquin River (SJR) flow objectives for the protection of fish and wild

The State Water Resources Control Board (State Water Board) is in the process of reviewing the San Joaquin River (SJR) flow objectives for the protection of fish and wildlife beneficial uses, water quality objectives for the protection of southern delta agricultural beneficial uses, and the program of implementation for those objectives contained in the 2006 Water Quality Control Plan for the San Francisco Bay/Sacramento-San Joaquin Delta Estuary (2006 Bay- Delta Plan). Figure 1.1 displays the project area corresponding to SJR flow objectives and program of implementation and Figure 1.2 displays the project area for the southern Delta water quality objectives and program of implementation. The information and analytical tools described in this report (referred to hereafter as Draft Technical Report or Technical Report) are intended to provide the State Water Board with the scientific information and tools needed to consider potential changes to these objectives and their associated program of implementation. In this quasi-legislative process, State Water Board staff will propose amendments to the SJR flow objectives for the protection of fish and wildlife beneficial uses, southern Delta water quality objectives for the protection of agricultural beneficial uses, and the program of implementation contained in the 2006 Bay-Delta Plan. Also, the environmental impacts of these amendments will be evaluated in a Substitute Environmental Document (SED) in compliance with the California Environmental Quality Act. Any changes to water rights consistent with the revised program of implementation will be considered in a subsequent adjudicative proceeding.

Technical Workshop on Estuarine Habitat in the Bay Delta Estuary

San Francisco Estuary Institute (SFEI) | March 27th, 2012

The Technical Workshop on Estuarine Habitat in the Bay Delta Estuary was initiated by U.S. Environmental Protection Agency (EPA), with support from the Aquatic

The Technical Workshop on Estuarine Habitat in the Bay Delta Estuary was initiated by U.S. Environmental Protection Agency (EPA), with support from the Aquatic Science Center (ASC), to obtain scientific input needed to inform EPA on California’s Comprehensive Review of the 2006 Water Quality Control Plan for the Bay Delta Estuary. Gathering a number of recognized experts on the hydrology and ecology of the Bay Delta was an efficient way to hear current knowledge on estuarine habitat, tools for modeling and assessing conditions, and how biological indicators and ecological processes respond to movement of the low salinity zone.  More specifically, the purpose of the workshop was to: Increase our collective understanding about the attributes of estuarine habitat, and the tools we have for protecting it Characterize the response of biological indicators and ecological processes to changing locations of the low salinity zone (LSZ) Generate scientific information that EPA and others can translate into recommendations that support the State’s Comprehensive Review of the 2006 Water Quality Control Plan (WQCP) for the Bay Delta Estuary The following sections describe planning for the workshop and the workshop process itself. The workshop summary condenses the input from participants during the small workgroup sessions and the final plenary session. It captures the breadth of opinions, judgments, and viewpoints expressed without attempting to fact check statements, or reconcile / synthesize disagreements or contradictions. Finally, the facilitator’s report provides my personal impressions of the workshop and the degree to which it achieved its stated purposes.

Temporal changes in the vertical distribution of flow and chloride in deep wells

National Groundwater Association (NGWA) | July 4th, 2005

The combination of flowmeter and depth‐dependent water‐quality data was used to evaluate the quantity and source of high‐chloride water yielded from different depth

The combination of flowmeter and depth‐dependent water‐quality data was used to evaluate the quantity and source of high‐chloride water yielded from different depths to eight production wells in the Pleasant Valley area of southern California. The wells were screened from 117 to 437 m below land surface, and in most cases, flow from the aquifer into the wells was not uniformly distributed throughout the well screen. Wells having as little as 6 m of screen in the overlying upper aquifer system yielded as much as 50% of their water from the upper system during drought periods, while the deeper parts of the well screens yielded 15% or less of the total yield of the wells. Mixing of water within wells during pumping degraded higher‐quality water with poorer‐quality water from deeper depths, and in some cases with poorer‐quality water from the overlying upper aquifer system. Changes in the mixture of water within a well, resulting from changes in the distribution of flow into the well, changed the quality of water from the surface discharge of wells over time. The combination of flowmeter and depth‐dependent water quality data yielded information about sources of high‐chloride water to wells that was not available on the basis of samples collected from nearby observation wells. Changing well design to eliminate small quantities of poor‐quality water from deeper parts of the well may improve the quality of water from some wells without greatly reducing well yield.

Temporal variability in irrigated land and climate influences on salinity loading across the Upper Colorado River Basin, 1986-2017

Environmental Research Letters (IOP) | January 19th, 2024