Accounting for Water "Wasted to the Sea"

University of California, Davis (UC Davis) | April 19th, 2018

Freshwater outflow from the Sacramento–San Joaquin Delta is a contentious management issue. Once mixed with salt water of San Francisco Bay, outflow is often characteri

Freshwater outflow from the Sacramento–San Joaquin Delta is a contentious management issue. Once mixed with salt water of San Francisco Bay, outflow is often characterized as having no value for urban and agricultural water supply, and thus “wasted to the sea.” In the July issue of San Francisco Estuary and Watershed Science, Cloern et al. (2017) showed how outflow from the Delta provides multiple and diverse benefits to the San Francisco estuary. Rather than being “wasted,” this outflow improves ecosystem conditions and water quality, and reduces wastewater treatment costs. The Cloern et al. (2017) essay highlights the importance of considering the multiple benefits of water as it moves within and out of the Delta. To do this, however, California needs a better water accounting system. In this report, we present an alternative approach. For the period 1980–2016, we assign inflow to the Delta to four categories: 1. Water used for diversions, 2. Outflow needed to meet salinity standards for diversions, 3. Outflow to meet ecosystem regulations, and 4. Water that results in outflow because of a lack of capacity for diversion. This approach highlights that much of the outflow from the Delta — particularly during dry periods — achieves multiple economic and environmental benefits and is hardly “wasted to the sea.”

Achieving State Goals for the Sacramento-San Joaquin Delta

Legislative Analyst's Office (LAO) | January 15th, 2015

The Sacramento-San Joaquin Delta (Delta) is a biodiverse ecosystem that covers about 1,150 square miles and supports over 700 species of fish and wildlife. The Delta is a

The Sacramento-San Joaquin Delta (Delta) is a biodiverse ecosystem that covers about 1,150 square miles and supports over 700 species of fish and wildlife. The Delta is an important source of water for the state and is used to convey water from Northern California to Southern California. The Delta faces several significant problems, including: (1) a decline in key native fish species, (2) reductions in the amount of Delta water available for use elsewhere, (3) water pollutants that cause harm to species and increase treatment costs, and (4) levees at significant risk of failure. The state has engaged in numerous efforts to address these problems and achieve its "coequal goals" for the Delta: water supply reliability and ecosystem restoration. There are many opportunities for the Legislature to improve the success of these efforts. We identified several issues for its consideration, including (1) demands for Delta water, (2) uncertain funding sources and slow implementation of some key activities, (3) limits on the effectiveness of governance in the Delta, and (4) challenges to restoring the Delta ecosystem. By addressing some of these issues, the Legislature can improve the likelihood that its goals and objectives for the Delta will be realized.

Adaptation Pathways: San Leandro Operational Landscape Unit

San Francisco Estuary Institute (SFEI) | May 15th, 2022

Given the diverse uses and conditions of San Francisco Bay’s 400-mile shoreline, a framework is needed to guide development of adaptation strategies appropriate to loca

Given the diverse uses and conditions of San Francisco Bay’s 400-mile shoreline, a framework is needed to guide development of adaptation strategies appropriate to local conditions. Operational Landscape Units (OLUs), outlined for the San Francisco Bay in the San Francisco Bay Shoreline Adaptation Atlas (SFEI and SPUR 2019), share common physical characteristics and therefore can benefit from being managed as individual units. OLUs cross traditional jurisdictional boundaries (cities, counties), and instead follow the boundaries of natural processes like tides, waves, and sediment movement. By planning at the OLU scale, it is possible to prioritize adaptation strategies that work synergistically. Coordinated OLU planning can help avoid unintended impacts on neighboring locales and identify synergies to make use of limited resources in a more efficient manner.

Adapting Restoration for a Changing Climate Symposium

Delta Stewardship Council (Delta Council) | November 5th, 2021

Adaptive Management and Science for the Delta Ecosystem

University of California, Davis (UC Davis) | October 1st, 2013

Using science to adaptively guide management for the Sacramento-San Joaquin Delta is widely talked about as good public policy.  Almost every agency, stakeholder, and pl

Using science to adaptively guide management for the Sacramento-San Joaquin Delta is widely talked about as good public policy.  Almost every agency, stakeholder, and planning process professes support and has its own adaptive management and science efforts.  But highly fragmented adaptive management and science cannot solve such urgent complex problems. California’s 2009 Delta Reform Act recognized that meeting the co-equal goals of a sustainable ecosystem and water supply reliability in the Delta required major changes in governance, planning, and management. Such changes also require major changes in how science is organized and employed in management. Here is a straw proposal for integrating the many parochial science and adaptive management programs for the Delta.

Addendum to the State Water Project and Central Valley Project Drought Contingency Plan

California Department of Water Resources (DWR) | August 31st, 2022

This Addendum includes current hydrologic conditions, plus updates on the following: operations status and the latest SWP and CVP (collectively referred to as Projects) o

This Addendum includes current hydrologic conditions, plus updates on the following: operations status and the latest SWP and CVP (collectively referred to as Projects) operations forecasts; species status; and known WY 2022 drought actions.

Addressing Multiple Stressors and Multiple Goals in the Delta Plan

Delta Stewardship Council (Delta Council) | January 26th, 2011

Advancement of Salinity and Flow Monitoring in the San Francisco Bay Delta, San Francisco Bay Delta Action Plan Implementation Support, FINAL REPORT

U.S. Geological Survey (USGS) | February 1st, 2017

This report evaluates the cost and utility of adding coupled surface and near-bottom salinity monitors along the axis of the San Francisco Estuary, and the types

This report evaluates the cost and utility of adding coupled surface and near-bottom salinity monitors along the axis of the San Francisco Estuary, and the types of equipment and approximate costs of this additional monitoring effort. Expanding the monitoring network by adding downstream monitoring stations, adding stations at depth, and increasing the resolution of monitoring stations along the axis of the estuary will generate data that capture tidal dynamics and may be used to derive equations that predict salinity and other hydrodynamic endpoints with greater precision than currently possible. The proposed monitoring is expected to enhance the hydrodynamic modeling of the salt field and the accuracy of compliance and prediction methods in the estuary. Springtime outflows through the San Francisco Estuary are managed through the position of the 2 parts per thousand bottom salinity isohaline (X2) along the center-line of the estuary, measured in kilometers relative to the Golden Gate Bridge. X2 is calculated from surface salinity measurements with a constant vertical conversion factor. The current framework of sampling stations does not collect near-bottom salinity along the estuary center-line, does not extend far enough down-estuary to adequately characterize X2 during high flows, and the separation of monitoring locations limits the precision with which the position of X2 can be calculated. Near-surface and near-bed salinity and turbidity sensors and ancillary hardware could be added to the estuary for an estimated cost of ~ $780K in capital costs and $500K/yr in operation, maintenance, and data processing costs based on a proposed addition to an existing surface salinity network in San Francisco Estuary operated by the US Geological Survey. While this document does not recommend a particular plan for implementation, the compiled information provides rough costs for planning considerations. Data collected through a network of this kind could improve precision of compliance methods with the existing Delta outflow standard. With data collected over time, it would support modifications to a new/modified Delta outflow standard, improve our ability to assess the effectiveness of water quality standards, and improve protection of water supply and aquatic life habitat. These data would also improve the salinity modeling capability and accuracy for future predictions and past evaluations. Expanding the monitoring network also provides a platform to connect hydrodynamic and biological measurements which is necessary for integrating biological and hydrodynamic modeling and advancing knowledge of estuarine mechanisms that influence fish population trends. The specific design of a monitoring network and whether or not the improvements can be optimized for their potential outputs was beyond the scope of the present document and needs to be based on a broader discussion among science experts, regulators, and the regulated community.

Age Determination of the Remaining Peat in the Sacramento–San Joaquin Delta, California, USA

U.S. Geological Survey (USGS) | October 9th, 2007

The Sacramento–San Joaquin Delta of California was once a 1,400 square kilometer (km2) tidal marsh, which contained a vast layer of peat ranging up to 15 meters (m) thi

The Sacramento–San Joaquin Delta of California was once a 1,400 square kilometer (km2) tidal marsh, which contained a vast layer of peat ranging up to 15 meters (m) thick (Atwater and Belknap, 1980). Because of its favorable climate and highly fertile peat soils, the majority of the Delta was drained and reclaimed for agriculture during the late 1800s and early 1900s. Drainage of the peat soils changed the conditions in the surface layers of peat from anaerobic (having no free oxygen present) to aerobic (exposed to the atmosphere). This change in conditions greatly increased the decomposition rate of the peat, which consists largely of organic (plant) matter. Thus began the process of land-surface subsidence, which initially was a result of peat shrinkage and compaction, and later largely was a result of oxidation by which organic carbon in the peat essentially vaporized to carbon dioxide (Deverel and others, 1998; Ingebritsen and Ikehara, 1999). Because of subsidence, the land-surface elevation on farmed islands in the Delta has decreased from a few meters to as much as 8 m below local mean sea level (California Department of Water Resources, 1995; Steve Deverel, Hydrofocus, Inc., written commun., 2007). The USGS, in collaboration with the University of California at Davis, and Hydrofocus Inc. of Davis, California, has been studying the formation of the Delta and the impact of wetland reclamation on the peat column as part of a project called Rates and Evolution of Peat Accretion through Time (REPEAT). The purpose of this report is to provide results on the age of the remaining peat soils on four farmed islands in the Delta.

Agreement Between the United States of America and the State of California for Coordinated Operating Agreement for the Central Valley Project and the State Water Project

U.S. Bureau of Reclamation (USBR) | November 24th, 1986

The 1986 agreement between the Bureau of Reclamation and the Department of Water Resources for the coordinated operation of the Central Valley Project and the State Water

The 1986 agreement between the Bureau of Reclamation and the Department of Water Resources for the coordinated operation of the Central Valley Project and the State Water Project.