Hydrology of the San Bernardino and Eastern San Gabriel Mountains, California

U.S. Geological Survey (USGS) | July 15th, 1954

Man's successful occupancy and development of the arid and semiarid parts of the earth will always be a planned and slow process. Planning is necessary be- cause the amou

Man's successful occupancy and development of the arid and semiarid parts of the earth will always be a planned and slow process. Planning is necessary be- cause the amount and distribution of the precipitation will generally not support the food crops to which he is accustomed. To provide the soil with enough mois- ture for crops, supplemental waters must be obtained from ground-water sources, distant surface streams, or from storage in mountain reservoirs. The planning, financing, and development of these supplemental sources require the united effort of many individuals, and as the population increases, water supplies that were once adequate may become insufficient. Thus, man is continually faced with the problem of obtaining enough water of high enough quality to meet his in- creasing demands. The problem requires an under- standing of the natural laws of occurrence and distribution of the water in the air, on the earth's surface, and underground. All life is dependent on these sources of water.

Hydrology, Ecology, and Fishes of the Klamath River Basin (2008)

National Academy of Sciences (NAS) | January 1st, 2008

The Klamath River basin, which spans parts of southern Oregon and northern California, has been the focus of a prominent conflict over competing uses for water. Manag

The Klamath River basin, which spans parts of southern Oregon and northern California, has been the focus of a prominent conflict over competing uses for water. Management actions to protect threatened and endangered fish species in the basin have left less water available for irrigation in dry years and heightened tensions among farmers and other stakeholders including commercial fishermen, Native Americans, conservationists, hunters, anglers, and hydropower producers. This National Research Council report assesses two recent studies that evaluate various aspects of flows in the Klamath basin: (1) the Instream Flow Phase II study (IFS), conducted by Utah State University, and (2) the Natural Flow of the Upper Klamath Basin study (NFS), conducted by the U.S. Bureau of Reclamation (USBR). The report concludes that both studies offer important new information but do not provide enough information for detailed management of flows in the Klamath River, and it offers many suggestions for improving the studies. The report recommends that a comprehensive analysis of the many individual studies of the Klamath river basin be conducted so that a big picture perspective of the entire basin and research and management needs can emerge. Key Messages If these conclusions were borne out by studies incorporating experimental flows and monitored responses, managers would be able to have greater confidence that decisions to increase flows would have a beneficial effect on anadromous fishes in the lower river The Instream Flow Study Phase II did not include important water-quality attributes, such as dissolved oxygen levels, nutrient loadings, contaminants, and sediment concentrations, although each has important implications for the vitality of the fish populations of the Klamath River. The Natural Flow Study and the Instream Flow Study Phase II were major science and engineering investigations, but the linkage of one to the other was only partially achieved. The Natural Flow Study was seriously compromised by several fundamental issues, including its choice of a basic approach for understanding natural flows, choices of the models for calculations, and serious omissions of factors likely to influence river flows at the Iron Gate Dam gauge site. The basin and its biota have changed so much in the past century that the implications for the fishes of restoring natural flows are not clear. The committee concluded that the Natural Flow Study includes calculated flows that are at best first approximations to useful estimates of such flows. The committee found important shortcomings in the Instream Flow Study Phase II and its use of various models and data. Two major shortcomings use of monthly data and lack of tributary analyses are so severe that that they should be addressed before decision makers can use the outputs of the study to establish precise flow regimes with confidence. The most important outcome of the Instream Flow Study was that it indicated that increases in existing flows downstream from Iron Gate Dam probably would benefit fish populations through improved physical habitat associated with more water and through reduced water temperatures. There was a lack of a thorough assessment of the relationship between flow-data time series and the behavior of different species and life stages and the population dynamics of coho and Chinook salmon When the science needs for the basin are better characterized, the individual studies necessary to create a sound science-based body of knowledge for decision makers and managers will be more easily identified. current flow regime. These are improvements in flow because they include intra- and inter-annual variations and probably will enhance Chinook salmon growth and young-of-the-year production. is not possible to know how well the recommendations apply to any one species or to all the species as a whole. Indeed, most of the information was from Chinook salmon, which suggests that confidence in its applicability to that species would be greater than to other species. of the representativeness of the reaches used for detailed study, and the statistical approach to analyze the calculated set of instream flows did not use normalized data and did not have provisions for identifying serial autocorrelations.

Impact of Anthropogenic CO2 on the CaCO3 System in the Oceans

American Association for the Advancement of Science (AAAS) | July 16th, 2004

Rising atmospheric carbon dioxide (CO2) concentrations over the past two centuries have led to greater CO2 uptake by the oceans. This acidification process has changed

Rising atmospheric carbon dioxide (CO2) concentrations over the past two centuries have led to greater CO2 uptake by the oceans. This acidification process has changed the saturation state of the oceans with respect to calcium carbonate (CaCO3) particles. Here we estimate the in situ CaCO3 dissolution rates for the global oceans from total alkalinity and chlorofluorocarbon data, and we also discuss the future impacts of anthropogenic CO2 on CaCO3 shell–forming species. CaCO3 dissolution rates, ranging from 0.003 to 1.2 micromoles per kilogram per year, are observed beginning near the aragonite saturation horizon. The total water column CaCO3 dissolution rate for the global oceans is approximately 0.5  0.2 petagrams of CaCO 3-C per year, which is approximately 45 to 65% of the export production of CaCO 3.

Impact of extreme drought and incentive programs on flooded agriculture and wetlands in California’s Central Valley

PeerJ | June 29th, 2018

Between 2013 and 2015, a large part of the western United States, including the Central Valley of California, sustained an extreme drought. The Central Valley is recogniz

Between 2013 and 2015, a large part of the western United States, including the Central Valley of California, sustained an extreme drought. The Central Valley is recognized as a region of hemispheric importance for waterbirds, which use flooded agriculture and wetlands as habitat. Thus, the impact of drought on the distribution of surface water needed to be assessed to understand the effects on waterbird habitat availability.Methods: We used remote sensing data to quantify the impact of the recent extreme drought on the timing and extent of waterbird habitat during the non-breeding season (July–May) by examining open water in agriculture (rice, corn, and other crops) and managed wetlands across the Central Valley. We assessed the influence of habitat incentive programs, particularly The Nature Conservancy’s BirdReturns and The Natural Resources Conservation Service’s Waterbird Habitat Enhancement Program (WHEP), at offsetting habitat loss related to drought.Results: Overall, we found statistically significant declines in open water in post-harvest agriculture (45–80% declines) and in managed wetlands (39–60% declines) during the 2013–2015 drought compared to non-drought years during the period of 2000–2011. Crops associated with the San Joaquin Basin, specifically corn, as well as wetlands in that part of the Central Valley exhibited larger reductions in open water than rice and wetlands in the Sacramento Valley. Semi-permanent wetlands on protected lands had significantly lower (39–49%) open water in the drought years than those on non-protected lands while seasonal wetlands on protected lands had higher amounts of open water. A large fraction of the daily open water in rice during certain times of the year, particularly in the fall for BirdReturns (61%) and the winter for WHEP (100%), may have been provided through incentive programs which underscores the contribution of these programs. However, further assessment is needed to know how much the incentive programs directly offset the impact of drought in post-harvest rice by influencing water management or simply supplemented funding for activities that might have been done regardless. Discussion: Our landscape analysis documents the significant impacts of the recent extreme drought on freshwater wetland habitats in the Central Valley, the benefits of incentive programs, and the value of using satellite data to track surface water and waterbird habitats. More research is needed to understand subsequent impacts on the freshwater dependent species that rely on these systems and how incentive programs can most strategically support vulnerable species during future extreme drought.

Implementing Ecosystem Based Management

Duke Environmental Law & Policy Forum | June 7th, 2021

Importance of subsurface water for hydrological response during storms in a post-wildfire bedrock landscape

Nature Portfolio (Springer Nature) | June 29th, 2023

Improving Habitats Along Delta Levees: A Review of Past Projects and Recommended Next Steps

Delta Stewardship Council (Delta Council) | January 15th, 2016

This review of habitat improvements along Delta levees was conducted to support the development of the Delta Stewardship Council’s (Council) Delta Levee Investment Stra

This review of habitat improvements along Delta levees was conducted to support the development of the Delta Stewardship Council’s (Council) Delta Levee Investment Strategy (DLIS), which focuses on flood risk reduction as the primary purpose of State levee investments. The report is intended to provide guidance to the Council to ensure that those investments also contribute to long-term improvement of river corridors, with net benefits for fish and wildlife. The Council must ensure that the DLIS helps to implement the Delta Reform Act and the Delta Plan. The Delta Reform Act of 2009 established the Council and defined its mission: to achieve the coequal goals of water supply reliability for California and ecosystem restoration in the Delta, in a manner that protects and enhances the values of the Delta as an evolving place (Water Code section 85054). The Delta Plan includes 14 regulatory policies, including one that calls for levee projects to incorporate habitat benefits, where feasible, and another requiring the use of the best available science and adaptive management. This report is intended to support the application of best available science and adaptive management to habitat improvements along Delta levees. It should be noted that levee-related habitat improvements alone are not expected to provide all the ecosystem benefits needed by native species. These projects take place within the larger context of ecosystem restoration in the Delta and Suisun Marsh, which will require more natural functional flows, restoration and conservation of a wide range of habitat types1, improved water quality, and the management of nonnative invasive species. Nevertheless, given its significant role in Delta levee investments, the State must ensure that these habitat projects are part of a program that provides a net benefit for aquatic species in the Delta.

Improving Infrastructure for Wildlife

Social Science Research Network (SSRN) | February 25th, 2021

In Washington v. United States, 584 U.S. ___ (2018), the Supreme Court required Washington State to improve fish passage through almost 1,000 culverts originally built to

In Washington v. United States, 584 U.S. ___ (2018), the Supreme Court required Washington State to improve fish passage through almost 1,000 culverts originally built to allow streamflow under roads and highways. The case highlighted conflicts between wildlife needs and infrastructure development. Fish passage through outdated or ill-designed culverts is only a small facet of the larger problem of outdated wildlife infrastructure. Impinged migration corridors for ungulates, turtles, and other mobile taxa; levees disconnecting floodplains from rivers; poor water temperature controls on dams; and eroding ecological productivity accompanying aging of reservoirs exemplify the types of challenges to wildlife created by contemporary infrastructure.

Improving the Health of California’s Headwater Forests

Public Policy Institute of California (PPIC) | September 18th, 2017

California’s headwater forests are not thriving under current management practices, and changes are needed to make them more resilient to periodic drought and long-term

California’s headwater forests are not thriving under current management practices, and changes are needed to make them more resilient to periodic drought and long-term climate change. More active management of these lands is needed to improve forest health, reduce the risk of major wildfires and pest infestations, and maintain the flow of benefits provided by this critical natural infrastructure. Decades of fire suppression, an emphasis on short-term management priorities, weather extremes, and a warming climate have set the stage for the decline in forest resilience. Two-thirds of the state’s surface water supply originates in these mountainous forests. California stands to lose timber production, wildlife habitat, recreational opportunities, and water supply if this vital natural infrastructure continues to decline. Management options exist—prescribed fire, managed wildfire, mechanical thinning, and forest pest treatments—that can help rebuild resilience in these forests and prepare them for a challenging future.

Incentive-based Instruments for Freshwater Management

Pacific Institute | December 1st, 2015

This new synthesis report from the Pacific Institute and the Foundation Center provides a review of existing evidence about the use of incentive-based instruments worldwi

This new synthesis report from the Pacific Institute and the Foundation Center provides a review of existing evidence about the use of incentive-based instruments worldwide. Based on case studies, evaluations, journal articles, and white papers, the authors provide a detailed review of three incentive-based instruments: water trading, payment for ecosystem services, and water quality trading. The report and interactive tool highlight the importance of finding the right fit between a community’s water goals and the water management tool(s) it might choose and, perhaps most importantly, characterize the conditions required for their effective implementation. Originally commissioned by The Rockefeller Foundation, all of the results from this project: the synthesis report, interactive tool, and digital collection are freely available for funders, practitioners, and researchers to use, contribute to, and build on in their work.