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, 2015 through September 30, 2016

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

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.

Salton Sea Fisheries Long-term Monitoring Sampling Report: Summer 2017

California Natural Resources Agency (CNRA) | July 13th, 2017

In early 2016, historic indices of tilapia abundance at the Salton Sea appeared to have reversed: tilapia fry were no longer observed in places where fish were regularly

In early 2016, historic indices of tilapia abundance at the Salton Sea appeared to have reversed: tilapia fry were no longer observed in places where fish were regularly visible in the past, piscivorous bird numbers at the lake were severely reduced, anglers were only catching a small fraction of past numbers of fish, and only a few small fish kills were observed. As observations of these conditions continued in early 2017, the question of whether the tilapia population was still viable was the impetus for the California Department of Fish and Wildlife (CDFW) to re-initiate gillnetting efforts.

Salton Sea Management Program Conceptual Project Implementation and Cost Estimates to Meet State Board Targets

California Natural Resources Agency (CNRA) | April 27th, 2017

The Salton Sea Management Program (SSMP) has developed a 10-year plan for Phase I that envisions a range of activities for habitat creation and dust management as

The Salton Sea Management Program (SSMP) has developed a 10-year plan for Phase I that envisions a range of activities for habitat creation and dust management as the Salton Sea recedes over 2018–2028. The California State Water Resources Control Board (SWRCB), through an order revising Order WRO 2002–0013, outlines annual and cumulative target areas for restoration through creation of habitat and dust suppression projects. These targets are defined for each year, ranging from a cumulative 500 acres by January 1, 2019, to a cumulative 29,800 acres by January 1, 2029, with a minimum 50 percent of the area being designated for fish and wildlife habitat projects. Areas around the sea are proposed for restoration projects, specifically at the southern end of the sea near the inflows of the Alamo and New rivers, and the northern end of the sea near the inflow of the Whitewater River. In a prior document (Salton Sea Management Plan Phase I: 10 Year Plan, March 2018), an overview of the project areas and activities was presented. This document presents a high-level plan for achieving the annual goals in the SWRCB order, by means of creation of wet habitat and dust control areas in different parts of the Salton Sea lakebed. This document identifies conceptual habitat ponds to be created, the associated wetted areas, and the additional dust control areas required to meet the order targets. For each of the conceptual project areas, there are estimates for berm lengths, heights, and needs for additional infrastructure, such as pumps and pipelines, causeways for equipment access, and levee extensions along river channels for flood protection of newly created habitat. Planned cross sections for the different types of linear structures are shown. Cost estimates are provided for each of the project areas over time to develop a total cost estimate. The conceptual habitat and dust control areas are based on the best current information on Salton Sea bathymetry, and demonstrate a reasonable path forward to attain the State Board order targets. The costs associated with these targets as presented in this document can be used for additional planning as part of the SSMP over the next decade. It is recognized that the actual footprints of individual projects may change in future years as better information becomes available on lakebed elevations, and relationships with other non-SSMP projects for habitat and dust control are better understood. These cost estimates are a refinement of estimates presented in the Salton Sea Management Plan Phase I: 10-Year Plan (March 2017). The cost estimates incorporate the best available cost information, and include the development of conceptual berm designs and supporting infrastructure, such as water diversions, pumps, and pipelines, and levees for river extensions. For these reasons, the cost estimate presented here supersedes the March 2017 estimate of $383 million for the 10-year implementation. But, all cost estimates at this stage are considered preliminary, and subject to revision as new field and construction data become available, and as designs are adjusted to best meet overall program needs. In the remainder of this document, two key topics are presented. In Chapter 2, there are estimates of the projected elevations of the Salton Sea over the 2018–2028 period, based on a hydrologic model of the sea. This is needed to allow estimation of exposed lakebed with the goal of constructing new habitat under dry conditions. Proposed conceptual project footprints, design and cost assumptions, and cost summaries are presented in Chapter 3.

Salton Sea Management Program Phase I: 10-Year Plan

California Natural Resources Agency (CNRA) | March 1st, 2017

Under the leadership of Governor Edmund G Brown Jr., the 2014 California Water Action Plan set forth a vision for California water management that balances statew

Under the leadership of Governor Edmund G Brown Jr., the 2014 California Water Action Plan set forth a vision for California water management that balances statewide water supply security with the protection of public, economic and ecological health. The Salton Sea offers a unique opportunity to preserve these values by leveraging a convergence of support from federal, state, and local stakeholders for a smaller and sustainable sea achieved through the projects outlined in this plan. The Salton Sea is California’s largest lake. Thirty-five miles long and 15 miles wide, the desert lake extends from the Coachella Valley into the Imperial Valley. Though saltier than the ocean, the Sea supports an abundance of fish, a food source for millions of migratory birds on the Pacific Flyway. Managing the Sea’s natural, agricultural, andmunicipal water inflows to maximize bird and fish habitat and minimize fine-particle air pollution will allow California to protect regional health, ecological wealth and a stable water supply. The Salton Sea formed in the Salton Trough in Imperial and Riverside counties. Much of the trough is below sea level and has a long history of periodic inundation from the shifting delta of the Colorado River or from infrequent storm events. The last Colorado River inundation of the area occurred in 1905 when an irrigation canal inlet gate failed and flooded much of the area. Since then, lake inflows have been primarily from agricultural activities in the area. Inflows from the New and Alamo rivers are primarily farm return flow water, although there is some inflow from Mexico, particularly during large precipitation events. Over the last several decades, water levels at the Salton Sea have declined and salinity concentrations have increased due to climate fluctuations, agricultural conservation measures, cropping practices and reduced inflows from Mexico. Recent water transfers from the Imperial Valley have further accelerated the rate of lake elevation decline and have increased the rate of salinity concentration. Declining lake levels threaten important bird habitat and pose public health risk due to particulate air pollution. Over the last 40 years numerous ideas and plans have been proposed by various entities to restore the Salton Sea. None have been implemented for a variety of reasons, including lack of a shared vision, funding constraints, and reduced inflows. In 2015, Governor Edmund G. Brown Jr. formed the Salton Sea Task Force with principle staff and members of various state agencies to identify short- and medium- term goals to respond to air quality and ecological threats at the Salton Sea. The Task Force developed actions for the Salton Sea that included: Develop and implement the Salton Sea Management Program through departments within the California Natural Resources and Environmental Protection Agencies Improve public outreach and local partnerships Accelerate project implementation and delivery Meet a short-term goal of 9,000 acres to 12,000 acres of dust suppression and habitat projects Establish a medium-term goal of 18,000 acres to 25,000 acres of dust suppression and habitat projects. The State’s Salton Sea Management Plan (SSMP) has several phases of development to protect air quality and ecosystem values at the Salton Sea. This draft technical memorandum prepared by the State of California outlines the SSMP’s first, 10-year phase (Phase I Plan). It will guide State and federal actions to meet the commitments outlined in the Memorandum of Understanding (MOU) executed on August 31, 2016, and amended on January 18, 2017 by the Department of Interior (DOI) and the California Natural Resource Agency (CNRA). The MOU, among other things, identified a goal of developing projects to protect or improve air quality, wildlife habitat, and water quality as necessary to minimize human health and ecosystem impact at the Salton Sea in the mid-term. While guided by the MOU, the SSMP is a longer-term process that has been developed and will be implemented by the State of California. This first phase of development has been planned to expedite construction of habitat and to suppress dust on areas of playa that have been or will be exposed at the Salton Sea by 2028. The Phase I Plan outlines the process for developing additional management measurements for the Salton Sea that will be implemented in later phases. The Phase I Plan also addresses the requirements of Assembly Bill 1095 (Garcia 2015) by including those projects deemed “shovel-ready projects” and including estimates of cost. Those projects include: Water backbone infrastructure, which will provide conveyance of river and Salton Sea water to air quality and habitat projects. SSMP air quality and habitat projects associated with the water backbone infrastructure The CNRA’s Phase I Species Conservation Habitat Project (saline impoundments along the southern shore to support fish and wildlife) Red Hill Bay Project, an effort of the U.S. Fish and Wildlife Service and Imperial Irrigation District to restore habitat on the southeastern shore. Torres-Martinez Wetland project, an effort of the Torres Martinez Desert Cahuilla Indians to build shallow wetlands along the northern edge of the Salton Sea. The Phase I Plan considers the implications of the 17-year drought on the Colorado River. The drought may force reductions of Colorado River water to the Lower Basin States, which in turn could impact inflows to the Salton Sea. The U.S. Bureau of Reclamation, seven Colorado River basin states and key principals of several water management agencies have been developing a Drought Contingency Plan (DCP) that includes implemented and proposed actions to address the potential water shortage. The Department of Interior Order No. 3344 - Actions to Address Effects of Historic Drought on Colorado River Water Supplies (DOI, January18, 2017) further outlines the details of the DCP. One component of the Phase I Plan is to evaluate the current hydrologic modeling for the Salton Sea and to include some of the proposed actions in the model to evaluate their potential impact to Salton Sea inflows.   As the Air Quality Planning and Implementation section of this document notes, the air quality mitigation will consist of measures to keep exposed playa wet or vegetated. A series of Best Available Control Measures (BACM) are being evaluated by the Quantification Settlement Agreement (QSA) Water Transfer mitigation program, which was created under a 2003 agricultural-to-urban water transfer agreement involving the State of California, the Imperial Irrigation District, Coachella Valley Water District, and the San Diego County Water Authority. The work of determining these best strategies will be paid for by the QSA Joint Powers Authority. The Phase I Plan involves coordination among Imperial Irrigation District, Imperial County Air Pollution Control District, South Coast Air Quality Management District and other agencies to ensure that the latest information about how lakebed exposure may affect air quality is included in the development of BACM pilot projects. In order to provide ample time for public input into this plan, the SSMP will schedule several regional workshops to solicit input from community members and stakeholders as well as provide necessary time for general public comment. This process will be announced via the program’s website. Associated documents: Salton Sea Management Program Conceptual Project Implementation and Cost Estimates to Meet State Board Targets, 4/27/2018 Appendix 1. Figures Appendix 2. Cost Projections Appendix 3. Ten-Year Phase I Plan Schedule Plan Spanish Translation: Programa de Gestión de Salton Sea Fase I: Plan de 10 Años *Plan appendices index from California Natural Resources Agency.

Salton Sea Management Program Phase I: 10-Year Plan Appendix 2. Cost Projections

California Natural Resources Agency (CNRA) | March 1st, 2017

Salton Sea Management Program Phase I: 10-Year Plan Appendix 3. Plan Schedule

California Natural Resources Agency (CNRA) | March 1st, 2017

Salton Sea Restoration Fund The State Has Not Fully Funded a Restoration Plan and the State’s Future Mitigation Costs Are Uncertain

California State Auditor | November 1st, 2013

The Salton Sea, located in Riverside and Imperial counties in Southern California, is the State’s largest inland lake. The Salton Sea was formed in 1905 when Colorado

The Salton Sea, located in Riverside and Imperial counties in Southern California, is the State’s largest inland lake. The Salton Sea was formed in 1905 when Colorado River floodwater breached an irrigation canal being constructed in the Imperial Valley; it has since been primarily fed by agricultural drain water. According to experts, the Salton Sea serves as an important fishery and wildlife habitat and is a major stopping point for migratory birds along the Pacific flyway. However, beginning in 2003, a series of agreements know collectively as the Quantification Settlement Agreement (QSA), between the State, local water agencies, and other entities have required, among other things, a water transfer that has reduced the amount of water that flows into the Salton Sea (water transfer). To mitigate the effects of the water transfer, the QSA requires one of the local water agencies that is a party to the agreement to provide additional water (mitigation water) to the Salton Sea for 15 years, from 2003 to 2017. Experts anticipate that when the Salton Sea stops receiving this mitigation water, the water transfer will cause profound negative environmental impacts, including the loss of fishery habitat, exposure of soils to wind erosion, and declines in bird species because of the loss of food.

Salton Sea Study Status Report

U.S. Bureau of Reclamation (USBR) | January 9th, 2003

The Salton Sea is located in a closed basin in Riverside and Imperial Counties in southern California, south of Indio and north of El Centro. The Sea is situated

The Salton Sea is located in a closed basin in Riverside and Imperial Counties in southern California, south of Indio and north of El Centro. The Sea is situated in a closed basin, more than 200 feet below sea level and has no natural outlet. Although lakes have existed in this basin in the past, the current body of water formed in 1905 when a levee break along the Colorado River caused flows from the Colorado River to enter the basin for about 18 months. Since 1905, the Sea has fluctuated in size with varying inflow, and it recently has had a surface area of 365 square miles. A balance between inflowing water and evaporation sustains the Sea. With no outlet, any salts that are dissolved in the inflow are trapped, although some do precipitate. Salt concentrations are currently about 44,000 milligrams per liter (mg/L), or about 25 percent higher than ocean water. Salinity will continue to rise under current conditions. It is highly likely that in the future, the inflow to the Sea will be less than it has been in the past. A reduction in inflow would cause the Sea to shrink and cause salinity to rise faster than it would have without a reduction in inflow. A gradual increase in salinity and its consequences was recognized soon after the Sea was formed. Formulation of salinity control measures was reported as early as the mid-1950s. Since then, many alternatives have been proposed and analyzed. The alternatives presented in this report were developed to address the goals contained in the Salton Sea Reclamation Act of 1998. The Act directs the Secretary of the Interior to study options for managing the salinity and elevation of the Sea in order to preserve fish and wildlife health and enhance opportunities for recreation use and economic development while continuing the Sea’s use as a reservoir for irrigation drainage. The Act required that certain options be analyzed and required consideration of reduced inflows down to 800,000 acre-feet or less per year. Consideration of any option that included importation of water from the Colorado River was prohibited. Reporting requirements of the Act were met on January 27, 2000, when Secretary Babbit forwarded a draft EIS/EIR and several other reports to Congress. Since then, analyses have continued on options presented in those reports and on new options. The development and transmission of this report is not required by law. This report provides a summary of the current status of the evaluation of alternatives currently under consideration. The primary purpose of the planning study was to evaluate possible methods of controlling the salinity and elevation of the Sea. The study also includes elements that address other issues at the Sea, such as high levels of nutrients. Fourteen alternatives providing a range of salinity and elevation control benefits and costs are presented in this report. For ease of presentation and understanding, alternatives were divided into the following categories: Salinity control alternatives Salinity and elevation control alternatives Causeway/barrier alternatives (the terms causeway and barrier are interchangeable in this report) Specialized diking alternatives Methods to control salinity and elevation include pumping water out of the Sea with discharge to some remote location; pumping water out of the Sea with discharge to local desalting plants or evaporation ponds, possibly in combination with enhanced evaporation systems that would require disposal of salt residues near or within the Sea; and dividing the Sea through the construction of dikes so that one portion serves to concentrate and isolate salts from the remainder of the Sea. Each alternative is discussed briefly below. The present value cost estimates for each alternative are also mentioned below. Present value cost includes the initial construction cost plus funds that would need to be set aside today to fund operation, maintenance, and energy over a 30-year period. This status report makes no recommendation regarding future action relating to restoration of the Salton Sea. In fact, given that all of the alternatives identified to date are extremely expensive, it is difficult, if not impossible, to make any recommendation without a decision by Congress regarding the relative importance of the Sea in light of other pressing national priorities.