Water-Level and land-subsidence studies in the Mojave River and Morongo groundwater basins; 2007

U.S. Geological Survey (USGS) | June 25th, 2007

Since 1992, the U.S. Geological Survey (USGS), in cooperation with the Mojave Water Agency (MWA), has constructed a series of regional water-table maps for intermittent y

Since 1992, the U.S. Geological Survey (USGS), in cooperation with the Mojave Water Agency (MWA), has constructed a series of regional water-table maps for intermittent years in a continuing effort to monitor groundwater conditions in the Mojave River and Morongo groundwater basins. The previously published data, which were used to construct these maps, can be accessed on the interactive map. The associated reports describing the groundwater conditions for the Mojave River groundwater basin for 1992 (Stamos and Predmore, 1995), the Morongo groundwater basin for 1994 (Trayler and Koczot, 1995), and for both groundwater basins for 1996 (Mendez and Christensen, 1997); for 1998 (Smith and Pimentel, 2000), for 2000 (Smith, 2002), for 2002 (Smith and others, 2004), for 2004 (Stamos and others, 2004), and for 2006 (Stamos and others, 2007) can be accessed using this web site.

Watershed-scale Evaluation of Agricultural BMP Effectiveness in Protecting Critical Coastal Habitats: Final Report on the Status of Three Central California Estuaries

Central Coast Regional Water Quality Control Board (CCRWQCB) | April 30th, 2010

Along California's Central Coast, the Pajaro, Salinas, and Santa Maria Rivers drain to coastal estuaries that provide essential habitat for early life stages of commercia

Along California's Central Coast, the Pajaro, Salinas, and Santa Maria Rivers drain to coastal estuaries that provide essential habitat for early life stages of commercially and recreationally important marine fish species, threatened anadromous fish species, migratory birds, and other wildlife. These are the largest watersheds on the central coast and each contains year-round, intensively cultivated agricultural land that supports a $3.5 billion/year industry producing most of the nation's lettuce, artichokes, and crucifer crops. Runoff from irrigated agriculture constitutes a significant portion of river flow during most of the year, and a number of studies have documented pesticide occurrence and biological impacts in these watersheds. Evidence of pesticide impacts has encouraged diverse stakeholders to begin implementing farm management practices (MPs) to reduce pesticide concentrations and toxicity in agricultural runoff. This project is designed to complement ongoing evaluations of individual MPs with measurements of pesticide concentrations throughout the estuarine environments, including the water column, sediments, and in resident biota. Biological effects were measured at the organism and community levels. Chemical analyses emphasized pesticide impacts because previous research in these watersheds has indicated these are the primary chemicals of concern impacting beneficial uses. A broad suite of pesticides were measured, including legacy organochlorines, widely-used organophosphates, increasingly-used pyrethroids, herbicides and fungicides. Sampling in the three estuaries was conducted from January 2008 until October 2009. A total of fifteen sampling events were conducted in each estuary, and these were divided between eleven irrigation season events and four storm events. Storm and irrigation monitoring included water toxicity and chemistry analyses for pesticides. Samples were collected at multiple stations in the estuaries and in key tributaries flowing to the estuaries. In addition, sediment toxicity was assessed at eight estuary stations and the tributary stations during three irrigation season sampling events. Benthic community characterizations were also conducted in May and October 2008. All sediment samples were analyzed for pesticides, as well as grain size and total organic carbon. Pesticide analyses in resident fish and sand crab tissues were conducted once in each estuary. The goal of this project was to establish a baseline of estuary conditions with respect to pesticide impacts as MPs are beginning to be implemented.

Yolo Bypass Juvenile Salmon Utilization Study 2016— Summary of Acoustically Tagged Juvenile Salmon and Study Fish Releases, Sacramento River, California

U.S. Geological Survey (USGS) | September 12th, 2017

The Yolo Bypass is a flood control bypass in Sacramento Valley, California. Flood plain habitats may be used for juvenile salmon rearing, however, the potential value of

The Yolo Bypass is a flood control bypass in Sacramento Valley, California. Flood plain habitats may be used for juvenile salmon rearing, however, the potential value of such habitats can be difficult to evaluate because of the intermittent nature of inundation events. The Yolo Bypass Juvenile Salmon Utilization Study (YBUS) used acoustic telemetry to evaluate the movements and survival of juvenile salmon adjacent to and within the Yolo Bypass during the winter of 2016. This report presents numbers, size data, and release data (times, dates, and locations) for the 1,197 acoustically tagged juvenile salmon released for the YBUS from February 21 to March 18, 2016. Detailed descriptions of the surgical implantation of transmitters are also presented. These data are presented to support the collaborative, interagency analysis and reporting of the study findings.