Protocol for Closure of Delta Waterways

Office of Emergency Services | November 21st, 1997

This protocol describes the process for placing restrictions on vessel traffic on the San Joaquin/Sacramento Delta waterways during periods of high water levels and flood

This protocol describes the process for placing restrictions on vessel traffic on the San Joaquin/Sacramento Delta waterways during periods of high water levels and flood events that involve conditions of disaster or extreme peril to the safety of persons and property. Restrictions will provide for flood fight priorities and control of vessel wakes that may exacerbate levee erosion or overtopping.

Prototyping structured decision making for water resource management in the San Francisco Bay-Delta

Environmental Science & Policy (Elsevier) | May 2nd, 2024

A structured decision making (SDM) approach can help evaluate tradeoffs between conservation and human-benefit objectives by fostering communication and knowledge transfe

A structured decision making (SDM) approach can help evaluate tradeoffs between conservation and human-benefit objectives by fostering communication and knowledge transfer among stakeholders, decision makers, and the public. However, the process is iterative and completing the full process may take years. It can be difficult to initiate an SDM effort when problems seem insurmountable. Occasionally, SDM may not even be the best or correct approach for addressing the conservation problem at hand. We describe the implementation of an SDM process to help inform difficult decisions related to competing objectives. We convened a diverse stakeholder group from the largest estuary in the western United States; the San Francisco Bay and Sacramento-San Joaquin Delta (Bay-Delta). The stakeholder group consisted of representatives from local, state, and federal agencies, non-profit organizations, and recreational fishers. The stakeholder group agreed on a problem statement and identified four priority objectives related to Chinook salmon, delta smelt, water availability and reliability, and agricultural water use. Furthermore, they proposed 14 candidate management actions to achieve their objectives. The group then used existing quantitative models and data to evaluate trade-offs in proposed management actions to identify areas of agreement of proposed candidate actions. The clear communication of the problem statement and objectives among the stakeholder group, along with evaluation of tradeoffs and uncertainty via decision-support models suggest that a full SDM approach may work in the Bay-Delta. We further communicate lessons learned during our implementation of SDM to help guide future SDM efforts in the region and elsewhere. See also: Structured Decision Making Delta Stewardship Council June 2024 meeting report.

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

Puzzling Over the Shallows

CALFED | December 1st, 2001

Quality Assurance Program Plan for The Regional Monitoring Program for Water Quality in San Francisco Bay

San Francisco Estuary Institute (SFEI) | June 23rd, 2017

The Regional Monitoring Program for Water Quality in San Francisco Bay (RMP) is managed and operated by the San Francisco Estuary Institute (SFEI). SFEI was founded as a

The Regional Monitoring Program for Water Quality in San Francisco Bay (RMP) is managed and operated by the San Francisco Estuary Institute (SFEI). SFEI was founded as a non-profit organization in 1986 to foster the development of the scientific understanding needed to protect and enhance the San Francisco Estuary.

Quantification of pre-screen loss of juvenile steelhead in Clifton Court Forebay

California Department of Water Resources (DWR) | August 26th, 2008

Recent advances in understanding flow dynamics and transport of water-quality constituents in the Sacramento–San Joaquin River Delta

University of California, Davis (UC Davis) | December 1st, 2016

This chapter describes advances during the past decade in understanding flow dynamics and how water-quality constituents, such as salinity, heat, oxygen, nutrients, conta

This chapter describes advances during the past decade in understanding flow dynamics and how water-quality constituents, such as salinity, heat, oxygen, nutrients, contaminants, and more, move within California’s Sacramento-San Joaquin River Delta. Water-quality constituents are affected by water diversions and other human manipulations of flow and they greatly affect the quantity and quality of habitats in the Delta. Along with human intervention, the Pacific Ocean, the Central Valley watershed, and the atmosphere, are a few drivers of flow and transport in the Delta. These drivers provide a conceptual framework for presenting recent findings. The tremendous expansion of acoustic and optical instruments utilized in the Delta over the past decade has greatly improved our understanding of how tidal variability affects flow and transport. Sediment is increasingly viewed as a diminishing resource needed to sustain habitat and tidal marsh, especially as sea level rises. Connections between the watershed, Delta, and San Francisco Bay that have been studied recently highlight that a landscape view of this system is needed rather than consideration of each region individually. Interactions of multiple drivers and information gaps are discussed.

Recent Scientific Contributions by the U.S. Geological Survey in the San Francisco Bay and Sacramento–San Joaquin Delta Estuary

U.S. Geological Survey (USGS) | January 26th, 2026

Recommendations for a Modeling Framework to Answer Nutrient Management Questions in the Sacramento-San Joaquin Delta

San Francisco Estuary Institute (SFEI) | March 1st, 2016

Management actions in the Delta related to nutrients could cost billions of dollars to implement in the coming decades depending on decisions that will come before the Ce

Management actions in the Delta related to nutrients could cost billions of dollars to implement in the coming decades depending on decisions that will come before the Central Valley Regional Water Quality Control Board (Water Board). The complexity of the Delta ecosystem and the range of questions to be addressed demand that numerical, processed-based water quality modeling be part of Delta management efforts. In light of this fact, the Water Board convened the Modeling Science Workgroup in 2015, and tasked it with advising on the development and use of water quality models as one component of the Water Board’s Nutrient Research Plan. The Charge to the Modeling Science Workgroup (included in Appendix B) was to provide advice to the Water Board on:  · The types of models would be needed to answer the nutrient management questions raised by stakeholders,  · Organizational arrangements to support and maximize the benefits of models, and  · Cost estimates for the modeling task and how such work might be phased over time. 

Reconciling fish and farms: Methods for managing California rice fields as salmon habitat

PLOS | February 24th, 2021

Rearing habitat for juvenile Chinook Salmon (Oncorhynchus tshawytscha) in California, the southernmost portion of their range, has drastically declined throughout the pa

Rearing habitat for juvenile Chinook Salmon (Oncorhynchus tshawytscha) in California, the southernmost portion of their range, has drastically declined throughout the past century. Recently, through cooperative agreements with diverse stakeholders, winter-flooded agricultural rice fields in California’s Central Valley have emerged as ecologically functioning floodplain rearing habitat for juvenile Chinook Salmon. From 2013 to 2016, we conducted a series of experiments examining methods to enhance habitat benefits for fall-run Chinook Salmon reared on winter-flooded rice fields in the Yolo Bypass, a modified floodplain managed for flood control, agriculture, and wildlife habitat in the Sacramento River Valley of California. Investigations included studying the effect of 1) post-harvest field substrate; 2) depth refugia; 3) duration of field drainage; and 4) duration of rearing occupancy on in-situ diet, growth and survival of juvenile salmon. Post-harvest substrate treatment had only a small effect on the lower trophic food web and an insignificant effect on growth rates or survival of rearing hatchery-origin, fall-run Chinook Salmon. Similarly, depth refugia, created by trenches dug to various depths, also had an insignificant effect on survival. Rapid field drainage yielded significantly higher survival compared to drainage methods drawn out over longer periods. A mortality of approximately one third was observed in the first week after fish were released in the floodplain. This initial mortality event was followed by high, stable survival rates for the remainder of the 6-week duration of floodplain rearing study. Across years, in-field survival ranged 7.4–61.6% and increased over the course of the experiments. Despite coinciding with the most extreme drought in California’s recorded history, which elevated water temperatures and reduced the regional extent of adjacent flooded habitats which concentrated avian predators, the adaptive research framework enabled incremental improvements in design to increase survival. Zooplankton (fish food) in the winter-flooded rice fields were 53-150x more abundant than those sampled concurrently in the adjacent Sacramento River channel. Correspondingly, observed somatic growth rates of juvenile hatchery-sourced fall-run Chinook Salmon stocked in rice fields were two to five times greater than concurrently and previously observed growth rates in the adjacent Sacramento River. The abundance of food resources and exceptionally high growth rates observed.