CVPIA 10 Years of Progress

U.S. Bureau of Reclamation (USBR) | June 27th, 2015

In 1992, Congress passed the Central Valley Project Improvement Act (Act, or CVPIA), which amended previous authorizations of the California Central Valley Project (CVP)

In 1992, Congress passed the Central Valley Project Improvement Act (Act, or CVPIA), which amended previous authorizations of the California Central Valley Project (CVP) to include fish and wildlife protection, restoration, enhancement, and mitigation as project purposes having equal priority with power generation, and irrigation and domestic water uses. Congress directed the Secretary of the Interior, through the Bureau of Reclamation (Reclamation) and the U.S. Fish and Wildlife Service (Service), to operate the CVP consistent with the purposes of the Act, to meet the Federal trust responsibilities to protect the fishery resources of affected Federally recognized Indian tribes, and to achieve a reasonable balance among competing demands for use of CVP water. For the past 10 years, Reclamation and the Service, working together to implement the CVPIA, have embarked on one of the Nation’s largest fish and wildlife restoration efforts. Reclamation and the Service have developed programs to improve environmental conditions and modify operations, management, and physical facilities, and thus, the associated environmental conditions of the CVP to comply with the purposes and goals of the Act. All of the Act’s restoration measures are planned and implemented by Reclamation and the Service and coordinated with the State of California, CALFED, and other partners. In the following pages, you will find a summary of the protection, restoration, enhancement, and mitigation measures that have been implemented as of the end of fiscal year 2002, demonstrating the contributions Reclamation and the Service have made to the Central Valley. As you read the summary, it should become clear that progress is being made in unprecedented programs, and advancements have been made in resolving complicated watershed issues throughout the Central Valley. Yet much work lies ahead.

Daily stream samples reveal highly complex pesticide occurrence and potential toxicity to aquatic life

Science of the Total Environment (Elsevier) | May 1st, 2020

Transient, acutely toxic concentrations of pesticides in streams can go undetected by fixed-interval sampling programs. Here we compare temporal patterns in occurrence of

Transient, acutely toxic concentrations of pesticides in streams can go undetected by fixed-interval sampling programs. Here we compare temporal patterns in occurrence of current-use pesticides in daily composite samples to those in weekly composite and weekly discrete samples of surface water from 14 small stream sites. Samples were collected over 10–14 weeks at 7 stream sites in each of the Midwestern and Southeastern United States. Samples were analyzed for over 200 pesticides and degradates by direct aqueous injection liquid chromatography with tandem mass spectrometry. Nearly 2 and 3 times as many unique pesticides were detected in daily samples as in weekly composite and weekly discrete samples, respectively. Based on exceedances of acute-invertebrate benchmarks (AIB) and(or) a Pesticide Toxicity Index (PTI) >1, potential acute-invertebrate toxicity was predicted at 11 of 14 sites from the results for daily composite samples, but was predicted for only 3 sites from weekly composites and for no sites from weekly discrete samples. Insecticides were responsible for most of the potential invertebrate toxicity, occurred transiently, and frequently were missed by the weekly discrete and composite samples. The number of days with benthic-invertebrate PTI ≥0.1 in daily composite samples was inversely related to Ephemeroptera, Plecoptera, and Trichoptera (EPT) richness at the sites. The results of the study indicate that short-term, potentially toxic peaks in pesticides frequently are missed by weekly discrete sampling, and that such peaks may contribute to degradation of invertebrate community condition in small streams. Weekly composite samples underestimated maximum concentrations and potential acute-invertebrate toxicity, but to a lesser degree than weekly discrete samples, and provided a reasonable approximation of the 90th percentile total concentrations of herbicides, insecticides, and fungicides, suggesting that weekly composite sampling may be a compromise between assessment needs and cost.

Dam effects on bedload transport on the upper Santa Ana River, California, and implications for native fish habitat

River Research and Applications (Wiley) | May 23rd, 2019

Dams disrupt the flow of water and sediment and thus have the potential to affect the downstream geomorphic characteristics of a river. Though there are some well‐known

Dams disrupt the flow of water and sediment and thus have the potential to affect the downstream geomorphic characteristics of a river. Though there are some well‐known and common geomorphic responses to dams, such as bed armouring, the response downstream from any particular dam is dependent on local conditions. Herein, we investigate the response of the upper Santa Ana River in southern California, USA, to the construction of a large dam at the transition from mountains to valley, using calculations of bedload transport capacity on the mainstem below the dam and for major tributaries. Approximate sediment budgets were constructed for downstream reaches to estimate deposition and erosion rates for sand, gravel, and cobble particle sizes. Our results indicate that the classical response of bed armouring and erosion is likely limited to a short reach immediately below the dam. Farther downstream, though transport capacity is reduced by flow regulation by the dam, the channel reaches are likely to remain depositional but with reduced deposition rates. Persistent deposition, as opposed to erosion, is the result of the replenishment of flow and sediment supply by large downstream tributaries. In addition, the calculations indicate that the composition of the bed is unlikely to change substantially in downstream reaches. A Monte Carlo approach was employed to estimate the uncertainty in the sediment budget predictions. The impacts of the dam on the geomorphic character of the river downstream could have implications for native fish that rely on coarse substrate that supports their food base.

DDT Residues in Pacific Sea Birds: a Persistent Insecticide in Marine Food Chains

Nature Portfolio (Springer Nature) | November 1st, 1967

THE accumulation and biological concentration of DDT and its metabolites*within food chains of terrestrial, freshwater and estuarine ecosystems have been well doc

THE accumulation and biological concentration of DDT and its metabolites*within food chains of terrestrial, freshwater and estuarine ecosystems have been well documented. Significant residue concentrations have occasionally been reported in marine organisms, but these have usually been attributed to local sources of contamination4. The present study, which is based on analyses of collections of birds, fish and invertebrates from Pacific Ocean localities, indicates that DDT is also a component of marine ecosystems and that pelagic species may accumulate high concentrations of DDT residues. The results of the work with fish will be published elsewhere.

Dealing with the Delta: Envisioning Futures, Finding Solutions (Research Brief)

Public Policy Institute of California (PPIC) | February 15th, 2007

This research brief summarizes a report by Jay Lund, Ellen Hanak, William Fleenor, Richard Howitt, Jeffrey Mount, and Peter Moyle, Envisioning Futures for the Sacramento�

This research brief summarizes a report by Jay Lund, Ellen Hanak, William Fleenor, Richard Howitt, Jeffrey Mount, and Peter Moyle, Envisioning Futures for the Sacramento–San Joaquin Delta.

Death Valley

Scientific American | August 22nd, 1903

Judging from the many high sensation stories and frequent references to Death Valley, there is evidently a popular interest in that dreaded locality, which is in part e

Judging from the many high sensation stories and frequent references to Death Valley, there is evidently a popular interest in that dreaded locality, which is in part explicable by the name it bears. The stories published are, as a rule, of little value, and give no idea of the climate, topography, fauna, and flora of a more absolute and arid desert than the Sahara. Our great deserts of the southwest have been but little written about by geographers and travelers, and it is only recently that accurate official reports upon them have been made. Capt. Clarence E . Dutton, in his report on the Grand Canon, gave a description of the deserts of northern Arizona. Captain Gaillard, of the Mexican Boundary Commission, has given us, in a popular magazine, probably the best article that has as yet been written on an American desert. He was well qualified to write, because he traversed the entire region from the Rio Grande to the Pacific, erecting monument s to mark the boundary between Mexico and the United States. Mr. W.J. McGee, Chief of the Bureau of American Ethnology, who recently made the journey through Southern Arizona and Mexico, to study the Seri Indians, who live on the Isle of Tiburon in the Gulf of California, has given us a fine description of the desert in his report and in separate articles in the Journal of Geography. A valuable article on the American Desert, by Robert T. Hill, has just appeared.

Decision on Petition for Rulemaking to Set Permanent Minimum Flows on the Shasta River

California State Water Resources Control Board (SWRCB) | February 16th, 2024

Decline of the world's saline lakes

Nature Portfolio (Springer Nature) | October 23rd, 2017

Many of the world's saline lakes are shrinking at alarming rates, reducing waterbird habitat and economic benefits while threatening human health. Saline lakes are long-t

Many of the world's saline lakes are shrinking at alarming rates, reducing waterbird habitat and economic benefits while threatening human health. Saline lakes are long-term basin-wide integrators of climatic conditions that shrink and grow with natural climatic variation. In contrast, water withdrawals for human use exert a sustained reduction in lake inflows and levels. Quantifying the relative contributions of natural variability and human impacts to lake inflows is needed to preserve these lakes. With a credible water balance, causes of lake decline from water diversions or climate variability can be identified and the inflow needed to maintain lake health can be defined. Without a water balance, natural variability can be an excuse for inaction. Here we describe the decline of several of the world's large saline lakes and use a water balance for Great Salt Lake (USA) to demonstrate that consumptive water use rather than long-term climate change has greatly reduced its size. The inflow needed to maintain bird habitat, support lake-related industries and prevent dust storms that threaten human health and agriculture can be identified and provides the information to evaluate the difficult tradeoffs between direct benefits of consumptive water use and ecosystem services provided by saline lakes.

Delta Adapts: Creating a Climate Resilient Future

Delta Stewardship Council (Delta Council) | June 25th, 2021

The time to act is now. Climate change is already altering the physical environment of the Sacramento–San Joaquin Delta and Suisun Marsh (Delta), and we will continue t

The time to act is now. Climate change is already altering the physical environment of the Sacramento–San Joaquin Delta and Suisun Marsh (Delta), and we will continue to experience its effects through hotter temperatures, more severe wildfires, and prolonged droughts. Over the long term, climate change in the Delta is expected to harm human health and safety, disrupt the economy, diminish water supply availability and usability, shift ecosystem function, compromise sensitive habitats, and increase the challenges of providing basic services. Many of these impacts will disproportionately affect vulnerable communities. Although the exact extent and timing of these impacts is uncertain, this climate change vulnerability assessment phase of Delta Adapts will help the Delta Stewardship Council (Council) understand specific regional climate risks and vulnerabilities. Regional, collaborative adaptation strategies rooted in science are more critical than ever. The next phase of Delta Adapts, preparing an adaptation strategy, will identify ways to address the risks and vulnerabilities.

Delta Adapts: Creating a Climate Resilient Future

Delta Stewardship Council (DSC) | June 25th, 2025

The Delta Stewardship Council (Council) was established, in part, to provide sustainable management for the Delta ecosystem, and climate adaptation is a critical consider

The Delta Stewardship Council (Council) was established, in part, to provide sustainable management for the Delta ecosystem, and climate adaptation is a critical consideration to achieve that mission in future decades. To respond to the challenge of climate adaptation,the Council developed this initiative, Delta Adapts: Creating a Climate Resilient Future (Delta Adapts). Climate change must be considered to attain the state’s coequal goals, as established by the 2009 Delta Reform Act: securing a reliable water supply for California, protecting and restoring the ecosystem and wildlife it supports, and enhancing the Delta as a unique place, with its community, tribal, and agricultural heritage. The Council adopted the Delta Plan, which has regulatory policies that protect land for restoration and agriculture, help manage flood risk, and improve water supply reliability. The Delta Plan directs the Council to guide and regulate actions of the 200+ state and local agencies in the Delta to ensure they support statewide water supply reliability and Delta ecosystem restoration.