Letter to Governor Brown and the Legislature on the Salton Sea

Little Hoover Commission | June 24th, 2016

The Little Hoover Commission in a letter sent Friday to Governor Brown and the Legislature again renewed its call for urgent action at the Salton Sea to prevent a massive

The Little Hoover Commission in a letter sent Friday to Governor Brown and the Legislature again renewed its call for urgent action at the Salton Sea to prevent a massive public health, environmental and economic disaster in Southern California. Policymakers must replicate the effective approach taken to meet the state’s rewewable energy goals, wrote the Commission in its letter. Then, the Govenor gave a senior official the authority to do what it took to get projects through red tape at all levels of government. The model was remarkably simple: Get everyone together and get it done. The letter results from continuing oversight to which the Commission pledged in its 2015 report, Averting Disaster: Action Now for the Salton Sea. The Commission held an April 2016 hearing to get an update on the state’s progress in strategically managing the Salton Sea. It heard from the assistant secretary for Salton Sea policy at the Natural Resources Agency, as well as stakeholders from local government and the environmental community. The Commission’s letter acknowledges that momentum is building and that the state has made important progress in managing the sea, particularly with $80 million in funding in the Governor’s proposed 2016-17 budget. However, the Commission’s letter maintains that the state is not moving fast enough or allocating sufficient resources to prevent a disaster. Timelines have been delayed, short-term goals scarcely cover a fraction of exposed lakebed and much more than $80 million is needed to manage the sea.

Linkage of In Vitro Assay Results With In Vivo End Points, Phases 1 and 2

San Francisco Estuary Institute (SFEI) | April 3rd, 2017

Our results clearly show that it is possible to establish linkages between the screening level in in vitro assays and higher order endpoints in fish that are infl

Our results clearly show that it is possible to establish linkages between the screening level in in vitro assays and higher order endpoints in fish that are influenced by estrogen, such as growth and gonadal sex differentiation (Table 1). As expected, the in vitro responses are the most sensitive endpoints tested and using them as a monitoring tool can provide a margin of safety for aquatic organisms that may be more sensitive to estrogenic chemicals than Menidia. Moreover, the margin of safety provided, represented by the ratio of in vivo to in vitro EC50s ranged from 0.9 to 9 for the potent estrogen E2 to 1.2 for E1 and 2.4 to 3.4 for NP (Table 1). There were no significant effects on growth, but merely trends, by any of the chemicals tested, suggesting that a higher “n” may be required to see appropriate effects on this endpoint. Using more concentrations for in vivo tests can refine these ratios.

Linking river management to species conservation using dynamic landscape-scale models

River Research and Applications (Wiley) | March 23rd, 2012

Efforts to conserve stream and river biota could benefit from tools that allow managers to evaluate landscape-scale changes in species distributions in response to water

Efforts to conserve stream and river biota could benefit from tools that allow managers to evaluate landscape-scale changes in species distributions in response to water management decisions. We present a framework and methods for integrating hydrology, geographic context and metapopulation processes to simulate effects of changes in streamflow on fish occupancy dynamics across a landscape of interconnected stream segments. We illustrate this approach using a 482 km2 catchment in the southeastern US supporting 50 or more stream fish species. A spatially distributed, deterministic and physically based hydrologic model is used to simulate daily streamflow for sub-basins composing the catchment. We use geographic data to characterize stream segments with respect to channel size, confinement, position and connectedness within the stream network. Simulated streamflow dynamics are then applied to model fish metapopulation dynamics in stream segments, using hypothesized effects of streamflow magnitude and variability on population processes, conditioned by channel characteristics. The resulting time series simulate spatially explicit, annual changes in species occurrences or assemblage metrics (e.g. species richness) across the catchment as outcomes of management scenarios. Sensitivity analyses using alternative, plausible links between streamflow components and metapopulation processes, or allowing for alternative modes of fish dispersal, demonstrate large effects of ecological uncertainty on model outcomes and highlight needed research and monitoring. Nonetheless, with uncertainties explicitly acknowledged, dynamic, landscape-scale simulations may prove useful for quantitatively comparing river management alternatives with respect to species conservation.

Listen to the River: An Independent Review of the CVPIA Fisheries Program

U.S. Bureau of Reclamation (USBR) | December 12th, 2008

In 1992 Congress directed the Department of Interior to develop and implement a program that makes “all reasonable efforts” to ensure and sustain on a long-term basis

In 1992 Congress directed the Department of Interior to develop and implement a program that makes “all reasonable efforts” to ensure and sustain on a long-term basis a doubling of the number of naturally produced anadromous fish in Central Valley rivers and streams by 2002. Doubling did not happen by the legislative goal of 2002, or by 2008, nor is it likely to ever occur unless renewed commitments and improvements are made to the CVPIA program. The specific “doubling” mission itself may make little scientific or policy sense, especially within the time frames demanded. Yet it is also far from clear that the agencies have done what is possible and necessary to improve freshwater conditions to help these species weather environmental variability, halt their decline and begin rebuilding in a sustainable way. A number of the most serious impediments to survival and recovery are not being effectively addressed, especially in terms of the overall design and operation of the Central Valley Project system. Underlying this independent review of the CVPIA anadromous fish program, asked for by the federal agencies, is the question why the CVPIA program has not been successful in achieving its mission. In this report, we identify scientific, institutional and programmatic obstacles to the success of the CVPIA, drawing conclusions from the information provided. Based on these conclusions, we make recommendations to Reclamation and the Service on how these obstacles might be overcome.

Local hydraulics influence habitat selection and swimming behavior in adult California Central Valley Chinook salmon at a large river confluence

Fisheries Research (Elsevier) | February 2nd, 2023

Long-term variation in concentrations and mass loads in a semi-arid watershed influenced by historic mercury mining and urban pollutant sources

Science of the Total Environment (Elsevier) | December 15th, 2017

Urban watersheds are significantly anthropogenically-altered landscapes. Most previous studies cover relatively short periods, without addressing concentrations, loads, a

Urban watersheds are significantly anthropogenically-altered landscapes. Most previous studies cover relatively short periods, without addressing concentrations, loads, and yields in relation to annual climate fluctuations, and datasets on Ag, Se, PBDEs, and PCDD/Fs are rare. Intensive storm-focused sampling and continuous turbidity monitoring were employed to quantify pollution at two locations in the Guadalupe River (California, USA). At a downstream location, we determined loads of suspended sediment (SS) for 14 yrs., mercury (HgT), PCBs, and total organic carbon (TOC) (8 yrs), total methylmercury (MeHgT) (6 yrs), nutrients, and trace elements including Ag and Se (3 yrs), DDTs, chlordanes, dieldrin, and PBDEs (2 yrs), and PCDD/Fs (1 yr). At an upstream location, we determined loads of SS for 4 yrs. and HgT, MeHgT, PCBs and PCDD/Fs for 1 yr. These data were compared to previous studies, climatically adjusted, and used to critically assess the use of small datasets for estimating annual average conditions. Concentrations and yields in the Guadalupe River appear to be atypical for total phosphorus, DDTs, dieldrin, HgT, MeHgT, Cr, Ni, and possibly Se due to local conditions. Other pollutants appear to be similar to other urban systems. On average, wet season flow varied by 6.5-fold and flow-weighted mean (FWM) concentrations varied 4.4-fold, with an average 7.1-fold difference between minimum and maximum annual loads. Loads for an average runoff year for each pollutant were usually less than the best estimate of long-term average. The arithmetic average of multiple years of load data or a FWM concentration combined with mean annual flow was also usually below the best estimate of long-term average load. Mean annual loads using sampled years were also less than the best estimate of long-term average by a mean of 2.2-fold. Climatic adjustment techniques are needed for computing estimates of long-term average annual loads.

Los Angeles Department of Water & Power response to Mono Lake Committee Request for a Drought Emergency Regulation

California State Water Resources Control Board (SWRCB) | January 11th, 2023

Los Angeles Department of Water and Power 2016 Annual Owens Valley Report

Los Angeles Department of Water & Power (LADWP) | December 1st, 2015

This report includes Los Angeles Department of Water and Power’s (LADWP) proposed Owens Valley operations plan for the first six months of the 2016-17 runoff year, an u

This report includes Los Angeles Department of Water and Power’s (LADWP) proposed Owens Valley operations plan for the first six months of the 2016-17 runoff year, an update on Owens Valley conditions, the current status of LADWP’s environmental mitigation projects, and the status of other studies, projects, and activities.

Loss and Transformation of Coastal Wetlands due to Global Change in the Conterminous United States: Past, Present, and Future

Publisher not available | June 26th, 2026

Coastal wetlands are being transformed by global change, impacting the ecological and societal benefits provided by these ecosystems. Synthesizing knowledge of historical

Coastal wetlands are being transformed by global change, impacting the ecological and societal benefits provided by these ecosystems. Synthesizing knowledge of historical and expected future transformations in coastal wetlands can help inform forward-looking planning and stewardship efforts. Here, we review anticipated future ecological transformations in coastal wetlands of the conterminous United States and contrast them with past transformations. We examine trends at the national scale but focus in detail on the following six wetland-rich regions: (1) Everglades, (2) Mississippi River delta, (3) Chesapeake Bay, (4) San Francisco Estuary, (5) Puget Sound, and (6) Great Lakes. This review is among the first to integrate and compare coastal wetland transformations in the Great Lakes with their oceanic counterparts. Between 1850 and 1970, wetland losses across the nation were high because coastal wetlands were viewed as flooded wastelands needing to be drained, filled, or excavated to make room for other land uses. Over the last 50 years, growing public and scientific appreciation of the ecological and societal benefits provided by coastal wetlands has fostered tremendous gains in wetland restoration and legal protection. Looking to the future, climate change and accelerated sea-level rise have become critical threats to coastal wetlands and are emerging as major drivers of ecological loss and transformation. This review synthesizes regional knowledge regarding past, present, and future changes to help coastal scientists, environmental managers, and the public better anticipate and prepare for future coastal wetland transformations due to climate change, accelerated sea-level rise, land-use change, and other aspects of global change.

Losses of Sacramento River Chinook Salmon and Delta Smelt to Entrainment in Water Diversions in the Sacramento-San Joaquin Delta

University of California, Davis (UC Davis) | June 30th, 2008

Pumping at the water export facilities in the southern Sacramento-San Joaquin Delta kills fish at and near the associated fish-salvage facilities. Correlative analyses of

Pumping at the water export facilities in the southern Sacramento-San Joaquin Delta kills fish at and near the associated fish-salvage facilities. Correlative analyses of salvage counts with population indices have failed to provide quantitative estimates of the magnitude of this mortality. I estimated the proportional losses of Sacramento River Chinook salmon (Oncorhynchus tshawytscha) and delta smelt (Hypomesus transpacificus) to place these losses in a population context. The estimate for salmon was based on recoveries of tagged smolts released in the upper Sacramento River basin, and recovered at the fish-salvage facilities in the south Delta and in a trawling program in the western Delta. The proportion of fish salvaged increased with export flow, with a mean value around 10% at the highest export flows recorded. Mortality was around 10% if pre-salvage losses were about 80%, but this value is nearly unconstrained. Losses of adult delta smelt in winter and young delta smelt in spring were estimated from salvage data (adults) corrected for estimated pre-salvage survival, or from trawl data in the southern Delta (young). These losses were divided by population size and accumulated over the respective seasons. Losses of adult delta smelt were 1–50% (median 15%) although the highest value may have been biased upward. Daily losses of larvae and juveniles were 0–8%, and seasonal losses accumulated were 0–25% (median 13%). The effect of these losses on population abundance was obscured by subsequent 50-fold variability in survival from summer to fall.