Sacramento River

Information for Parties Preparing Proposals for Water Transfers Requiring Department of Water Resources or Bureau of Reclamation Approval

California Department of Water Resources (DWR) | December 1st, 2015

Information for the Future: The West Side San Joaquin Valley Project

West Side San Joaquin Valley Coordinating Council, University of California, Water Resources Center | September 1st, 1970

Information Needs for Water Markets: Fair and Effective Water Markets Require Adequate Measurement and Reporting of Diversion and Use

University of California, Berkeley (UC Berkeley) | November 14th, 2024

Initial Alternatives Information Report for the North/Central Delta Improvement Study (Delta Cross Channel, Franks Tract, and Through- Delta Facility Evaluation)

U.S. Bureau of Reclamation (USBR) | March 17th, 2010

The U.S. Department of the Interior (Interior) Bureau of Reclamation (Reclamation) and the California Department of Water Resources (DWR) are evaluating the feasibility o

The U.S. Department of the Interior (Interior) Bureau of Reclamation (Reclamation) and the California Department of Water Resources (DWR) are evaluating the feasibility of using conveyance and operations actions in the north and central region of the Sacramento–San Joaquin River Delta (Delta) to improve water quality and fish conditions. Specifically, Reclamation is evaluating the feasibility of these actions in the North/Central Delta Improvement Study (NoCDIS or Study). The Initial Alternatives Information Report (IAIR) identifies, discusses, and screens measures to address the problems and opportunities. These measures are used to develop initial alternatives. Initial alternatives from the IAIR will be incorporated into and refined in the subsequent Plan Formulation Report (PFR). Subject to continued appropriations and a determination of federal interest, the Study should culminate in an Environmental Impact Statement/Environmental Impact Report (EIS/EIR) and a Feasibility Report. Reclamation is the federal lead agency for National Environmental Policy Act (NEPA) compliance, and DWR is the state lead agency for California Environmental Quality Act (CEQA) compliance.

Innovation in Monitoring: The U.S. Geological Survey Sacramento–San Joaquin River Delta, California, Flow-Station Network

U.S. Geological Survey (USGS) | January 1st, 2016

The U.S. Geological Survey (USGS) installed the first gage to measure the flow of water into California’s Sacramento–San Joaquin River Delta from the Sacramento River

The U.S. Geological Survey (USGS) installed the first gage to measure the flow of water into California’s Sacramento–San Joaquin River Delta from the Sacramento River in the late 1800s. Today, a network of 35 hydro-acoustic meters measure flow throughout the delta. This region is a critical part of California’s freshwater supply and conveyance system. With the data provided by this flow-station network—sampled every 15 minutes and updated to the web every hour—state and federal water managers make daily decisions about how much freshwater can be pumped for human use, at which locations, and when. Fish and wildlife scientists, working with water managers, also use this information to protect fish species affected by pumping and loss of habitat. The data are also used to help determine the success or failure of efforts to restore ecosystem processes in what has been called the “most managed and highly altered” watershed in the country.

Instream flow evaluation: Temperature and passage assessment for salmonids in Mill Creek, Tehama County

California Department of Fish and Wildlife (CDFW) | May 8th, 2017

Mill Creek is among the essential streams for recovery and perpetuation of wild stocks of Central Valley spring-run Chinook salmon (Oncorhynchus tshawytscha), and support

Mill Creek is among the essential streams for recovery and perpetuation of wild stocks of Central Valley spring-run Chinook salmon (Oncorhynchus tshawytscha), and supports Central Valley steelhead trout (Oncorhynchus mykiss; Armentrout et al. 1998). In addition, Mill Creek is utilized by fall-run Chinook salmon, late fall-run Chinook salmon, and Pacific Lamprey (Entosphenus tridentatus). The Recovery Plan for Central Valley Chinook Salmon and Steelhead (NMFS 2014) classified Mill Creek as a high priority Core 1 watershed because of its potential to support independent viable populations. Mill Creek is also identified as a priority stream in the State Water Resources Control Board (SWRCB) Instream Flow Studies for the Protection of the Public Trust Resources: A Prioritized Schedule and Estimate of Cost (SWRCB 2010), and the US Fish and Wildlife Service (USFWS) Final Restoration Plan for the Anadromous Fish Restoration Program: A Plan to Increase Natural Production of Anadromous Fish in the Central Valley of California (USFWS 2001). The California Department of Fish and Wildlife (Department) has interest in ensuring that water flows within streams are maintained at levels which are adequate for long-term protection, maintenance, and proper stewardship of fish and wildlife resources. The Department’s Instream Flow Program develops scientific information to determine what flows are needed to maintain healthy conditions for fish and wildlife. For each species of interest, life stage, and stream, relationships between flow and habitat are developed. The Department recommends using the federal Instream Flow Incremental Methodology (IFIM) to evaluate and develop instream flow criteria for projects which may affect California’s aquatic resources. The IFIM process, and instream flow evaluations, in general, should include broad consideration of the structure and function of riverine systems while also providing examination of five core components (i.e., hydrology, biology, geomorphology, water quality, and connectivity) of the riverine system. The Public Resources Code (PRC) §10000-10005 outlines the Department’s responsibilities for developing and transmitting flow criteria to the SWRCB for consideration as set forth in 1257.5 of the Water Code. The results from this study are intended to be used, along with other supporting information and data, to identify stream flow requirements necessary for upstream passage of adult Chinook salmon and steelhead into the upper Mill Creek watershed pursuant to the Department’s PRC mandate. Flow criteria for lower Mill Creek will be developed by the Department in a future document.

Instream Flow Studies for the Protection of Public Trust Resources: A Prioritized Schedule and Estimate of Costs

California State Water Resources Control Board (SWRCB) | February 18th, 2011

Chapter 5 of the 2009-10 Seventh Extraordinary Session (SB X7 1, Simitian) directs the State Water Resources Control Board (State Water Board) to submit to the Legislatur

Chapter 5 of the 2009-10 Seventh Extraordinary Session (SB X7 1, Simitian) directs the State Water Resources Control Board (State Water Board) to submit to the Legislature, by December 31, 2010, a prioritized schedule and estimate of costs to complete instream flow studies for two categories of rivers and streams, by two specific deadlines: 1) high priority rivers and streams in the Delta watershed that were not covered in the Board’s “Final Report on Development of Flow Criteria for the Sacramento-San Joaquin Delta Ecosystem” by 2012; and 2) all major rivers and streams outside the Sacramento River watershed by 2018. The definition of the two stream categories is ambiguous. There are a number of tributaries that are both in the Delta watershed and outside the Sacramento River watershed, including the San Joaquin, Calaveras, Cosumnes, and Mokelumne Rivers. The State Water Board interprets the first category to mean all Delta and Sacramento River tributaries not covered under the Board’s “Final Report on Development of Flow Criteria for the Sacramento-San Joaquin Delta Ecosystem.” Two additional schedules are prioritized for “all major rivers and streams outside the Sacramento River watershed.” This report identifies 138 rivers and streams for instream flow studies. The total estimated cost to conduct scientific instream flow studies for the high priority rivers and streams tributary to the Delta is $32.46 million. The total estimated cost to conduct scientific instream flow studies for the high priority rivers and streams outside the Delta watershed is $107.25 million. The detailed schedules and costs are preceded with a few short discussions on the timelines given in the directive, the organization of schedules, the cost estimates for instream flow studies, and cost estimates for the next logical step: setting instream flow objectives.

Integrated Management of Delta Stressors: Institutional and Legal Options

Public Policy Institute of California (PPIC) | April 22nd, 2013

Despite some recent progress, the current institutional landscape for regulation and management of stressors in the in the Sacramento–San Joaquin Delta is highly fragme

Despite some recent progress, the current institutional landscape for regulation and management of stressors in the in the Sacramento–San Joaquin Delta is highly fragmented. A modest but powerful set of institutional changes can help produce better environmental outcomes while containing management costs—which are likely to exceed several hundred million dollars annually. This report lays out proposals for institutional reform.

Integrated Water Operations in California: Hydropower, Overdraft, and Climate Change

University of California, Davis (UC Davis) | July 16th, 2015

Several management and climate cases are evaluated with the updated CALVIN, a hydro-economic optimization model of California’s inter-tied water supply infrastructure.

Several management and climate cases are evaluated with the updated CALVIN, a hydro-economic optimization model of California’s inter-tied water supply infrastructure. Updates to the CALVIN model include new projected 2050 agricultural target demands and scarcity penalties, improvements to network-flow representation, especially agricultural, urban, and wildlife refuge demands, and extended surface and ground water hydrology, now covering an 82-year historical inflow hydrology. A new energy price scheme is applied to CALVIN, which incorporates hourly energy price variations into monthly CALVIN operations. Using one constant average price for a month underestimates hydropower revenue and overestimates pumping costs. Hourly-varying moving average prices improved representation of hydropower revenue without creating significant scarcities to agricultural and urban water users. Effects of ending long-term groundwater overdraft in the Central Valley are evaluated with several management cases using CALVIN. The cases include effects of Delta outflow and Delta exports from a “no overdraft” policy. The least cost overdraft that minimizes groundwater pumping and scarcity costs is calculated for the 82-year period. Prohibiting Delta exports result in severe water scarcities south of the Delta. Water operations are more economical when overdraft is ended with adaptations, such as more Delta exports, increased groundwater banking, and water trades, than historical operations with overdraft. Finally, climate change effects under a warmer and drier climate scenario are studied and results are compared to historical hydrology. A drier and warmer climate shifts the timing and magnitude of stream flows. Spring snowmelt decreases and winter flows increase. Modelled reduction in rim inflows averages about 28%. This warmer-drier climate increases water scarcities, but adverse effects can be diminished with water sales, higher Delta exports, more conjunctive use, and wastewater recycling. 

Inter-population differences in salinity tolerance of adult wild Sacramento splittail: osmoregulatory and metabolic responses to salinity

Conservation Physiology (Society of Experimental Biology) | December 10th, 2020

The Sacramento splittail (Pogonichthys macrolepidotus) is composed of two genetically distinct populations endemic to the San Francisco Estuary (SFE). The allop

The Sacramento splittail (Pogonichthys macrolepidotus) is composed of two genetically distinct populations endemic to the San Francisco Estuary (SFE). The allopatric upstream spawning habitat of the Central Valley (CV) population connects with the sympatric rearing grounds via relatively low salinity waters, whereas the San Pablo (SP) population must pass through the relatively high-salinity Upper SFE to reach its allopatric downstream spawning habitat. We hypothesize that if migration through SFE salinities to SP spawning grounds is more challenging for adult CV than SP splittail, then salinity tolerance, osmoregulatory capacity, and metabolic responses to salinity will differ between populations. Osmoregulatory disturbances, assessed by measuring plasma osmolality and ions, muscle moisture and Na+-K+-ATPase activity after 168 to 336 h at 11 salinity, showed evidence for a more robust osmoregulatory capacity in adult SP relative to CV splittail. While both resting and maximum metabolic rates were elevated in SP splittail in response to increased salinity, CV splittail metabolic rates were unaffected by salinity. Further, the calculated difference between resting and maximum metabolic values, aerobic scope, did not differ significantly between populations. Therefore, improved osmoregulation came at a metabolic cost for SP splittail but was not associated with negative impacts on scope for aerobic metabolism. These results suggest that SP splittail may be physiologically adjusted to allow for migration through higher-salinity waters. The trends in interpopulation variation in osmoregulatory and metabolic responses to salinity exposures support our hypothesis of greater salinity-related challenges to adult CV than SP splittail migration and are consistent with our previous findings for juvenile splittail populations, further supporting our recommendation of population-specific management.