Sacramento River Delta 3D Mapping Project Technical Report

Delta Stewardship Council (Delta Council) | May 1st, 2018

This technical report is in response to item five in the Delta Stewardship Council project #6276. The data collection and analysis were completed by Freshwater Map of Big

This technical report is in response to item five in the Delta Stewardship Council project #6276. The data collection and analysis were completed by Freshwater Map of Bigfork, Montana. The objective of this phase-1 project was to demonstrate, to a broad audience, how our high-resolution, hydro-acoustic, river-mapping services could help people working toward water resource solutions for the delta. The overarching goal for the State of California is to balance human needs for freshwater with an ecological healthy river-delta system under the “co-equal goals” legislation. The fundamental question being addressed by all stakeholders is: how much water can be drawn from the delta and still maintain a healthy delta wide ecosystem? However, there is no agreement yet on how much the ecosystem needs or how a multitude of uses and flow regulation impacts both humans and the ecosystem. A suite of computer models has been developed and refined over the past two decades to address this fundamental question (Fig. 1). These models were developed to help guide resource decision agreement on how to manage freshwater that flows to and through the delta. The data that we collect can help initialize, validate and greatly enhance many of these models (Fig. 1). The data analysis presented in this technical report is a first pass summary of how the depth and flow data coupled to the sonar imagery can be used to help reach delta-wide agreement over water resource management .

Sacramento River Flood Control Project Weirs and Flood Relief Structures

California Department of Water Resources (DWR) | April 8th, 2011

Sacramento Valley has a history of floods and management of floods that goes back as long as people have populated the region. Prior to flood management, the valley floor

Sacramento Valley has a history of floods and management of floods that goes back as long as people have populated the region. Prior to flood management, the valley floor would be blanketed by seasonal runoff nearly every year; the Sacramento Valley was once nicknamed the “inland sea.” This tendency to flood results from the geography of the region as well as the weather. The occasionally large amounts of rain that fall in the surrounding Coastal ranges and the relatively steep Sierra Nevada mountain ranges produce rapid surface water runoff to the Sacramento River. The amount of this surface water runoff can be quite large, depending on the amount of rainfall, snow melt, and soil moisture of the watershed. Fast water flowing from the mountains is blunted by the relatively shallow grade of the Sacramento River south of the city of Red Bluff, and would often overtop the river banks. In addition, The Sacramento River would begin depositing sediment in the more shallow grades that would often alter its direction of flow. In order to control these storm flows that would otherwise flood farmland and cities, the Sacramento River Flood Control Project (the Project) was created. The Project was designed with the understanding that runoff from many of the storm events experienced in the Sacramento River watershed cannot be contained within the banks of the river. Nor could this flow be fully contained within a levee system without periodically flooding adjacent property. Thus, the Project was designed to occasionally spill through a system of weirs and flood relief structures into adjacent basins. These basins are designed to contain flood waters and channel them downstream, to eventually be conveyed back into the Sacramento River near Knights Landing and Rio Vista. Dry weather flows are contained within levees near the river banks and land within the flood basins is then used for agricultural purposes.

Sacramento River Temperature Task Group Annual Report of Activities October 1, 2013 through September 30, 2014

Delta Stewardship Council (Delta Council) | October 6th, 2014

Sacramento River Temperature Task Group Annual Report of Activities October 1, 2017 through September 30, 2018

Delta Stewardship Council (Delta Council) | November 21st, 2018

Sacramento River Temperature Task Group Annual Report of Activities, October 1, 2015 through September 30, 2016

Delta Stewardship Council (Delta Council) | October 31st, 2016

Sacramento-San Joaquin Delta Atlas

California Department of Water Resources (DWR) | July 1st, 1995

The Delta of the Sacramento and San Joaquin rivers is California's water supply crossroads. It is the major collection point for water that serves over 20 million people,

The Delta of the Sacramento and San Joaquin rivers is California's water supply crossroads. It is the major collection point for water that serves over 20 million people, two-thirds of our State's population. The maze of islands and channels lying at the confluence of these two large rivers has long been the focal point of debate surrounding a number of complicated water-related issues of statewide importance. People with a wide variety of interests - agricultural, urban, industrial, environmental, and recreational-have a vital stake in the Delta and a need to understand the physical Delta and its complex interrelationships. This atlas provides information that we hope will be helpful in addressing the complex problems of the estuary. The atlas is a revision of the Sacramento-San Joaquin Delta Atlas that was published in 1987. It contains updates on many Delta facts and features. It also introduces new information on the Suisun Marsh and tides and hydrology in the Delta as well as in San Francisco Bay.

Sacramento-San Joaquin Delta Historical Ecology Investigation: Exploring Pattern and Process

San Francisco Estuary Institute (SFEI) | September 12th, 2012

In 2012, SFEI researchers (in collaboration with the CA Department of Fish and Wildlife) completed a historical ecology study of the Sacramento-San Joaquin Delta. The

In 2012, SFEI researchers (in collaboration with the CA Department of Fish and Wildlife) completed a historical ecology study of the Sacramento-San Joaquin Delta. The project improves understanding of what the Delta looked like and how it functioned prior to the significant modification that has occurred over the last 160 years. This historical reconstruction documents patterns of variation and extent of habitat types throughout the Delta for improved understanding of species support functions and controlling physical processes within the native landscape. Knowing how different parts of the vast historical Delta looked and functioned provides needed information for future restoration strategies.

Sacramento/San Joaquin Delta Dilemma

Assembly Office of Research (AOR) | January 1st, 1982

Sailing the Salt Line

Bay Nature | July 2nd, 2024

A strait is a place of motion. Change is a constant in our universe, a fact we humans often struggle with, but certain places are especially good at reminding us of it. T

A strait is a place of motion. Change is a constant in our universe, a fact we humans often struggle with, but certain places are especially good at reminding us of it. The Carquinez Strait itself was only just born, some 560,000 years ago—explosively, according to one theory—when a giant inland lake forced a path to the ocean. This created the unusual inverted river delta (with the fan pointing inland, instead of spreading out onto the coast) that is the San Francisco Bay.

Salinity Changes the Dynamics of Pyrethroid Toxicity in Terms of Behavioral Effects on Newly Hatched Delta Smelt Larvae

Toxics (MDPI) | February 20th, 2021

Salinity can interact with organic compounds and modulate their toxicity. Studies have shown that the fraction of pyrethroid insecticides in the aqueous phase increases w

Salinity can interact with organic compounds and modulate their toxicity. Studies have shown that the fraction of pyrethroid insecticides in the aqueous phase increases with increasing salinity, potentially increasing the risk of exposure for aquatic organisms at higher salinities. In the San Francisco Bay Delta (SFBD) estuary, pyrethroid concentrations increase during the rainy season, coinciding with the spawning season of Delta Smelt (Hypomesus transpacificus), an endangered, endemic fish. Furthermore, salinity intrusion in the SFBD is exacerbated by global climate change, which may change the dynamics of pyrethroid toxicity on aquatic animals. Therefore, examining the effect of salinity on the sublethal toxicity of pyrethroids is essential for risk assessments, especially during the early life stages of estuarine fishes. To address this, we investigated behavioral effects of permethrin and bifenthrin at three environmentally relevant concentrations across a salinity gradient (0.5, 2 and 6 PSU) on Delta Smelt yolk-sac larvae. Our results suggest that environmentally relevant concentrations of pyrethroids can perturb Delta Smelt larvae behavior even at the lowest concentrations (<1 ng/L) and that salinity can change the dynamic of pyrethroid toxicity in terms of behavioral effects, especially for bifenthrin, where salinity was positively correlated with anti-thigmotaxis at each concentration.