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Design and methods of the California stream quality assessment (CSQA), 2017

U.S. Geological Survey (USGS) | April 21st, 2020

Summary

During 2017, as part of the National Water-Quality Assessment Project, the U.S. Geological Survey conducted the California Stream Quality Assessment to investigate the qu

During 2017, as part of the National Water-Quality Assessment Project, the U.S. Geological Survey conducted the California Stream Quality Assessment to investigate the quality of streams in the Central California Foothills and Coastal Mountains ecoregion, United States. The goal of the California Stream Quality Assessment study was to assess the health of wadeable streams in the region by characterizing multiple water-quality factors that are stressors to aquatic biota and by evaluating the relation between these stressors and biological indicators of stream health. Urbanization, agriculture, and modifications to streamflow are anthropogenic changes that affect water quality in the region; consequently, the study design primarily targeted sites and specific stressors associated with these activities. For the study, 85 stream sites were selected to represent the types and intensity of land use in the watershed; categories of site types were undeveloped, urban (low, medium, high), agriculture (low, high), and mixed (urban and agriculture). Most sites (about 70 percent) represent a gradient of urbanization from undeveloped to 99-percent urbanized. At most of the sites, streamgages or pressure transducers were used to monitor stream discharge and stage, as well as temperature. Water-quality samples were collected routinely at all sites and were analyzed for major ions, organic contaminants, nutrients, and suspended sediment. Sampling frequency varied on the basis of site type and location. Discrete water samples were collected weekly and generally 6 times per site, except for 11 undeveloped sites that were sampled only 4 times (during the last 4 weeks). Water sampling began at sites in the southern part of the study on March 13, 2017, and at sites in the northern part of the study on April 3, 2017. Passive samplers were deployed at most sites for measurement of polar organic contaminants (pesticides and pharmaceuticals). In May 2017, coincident with completion of water-quality sampling, an ecological survey was conducted at each site to assess benthic algal and macroinvertebrate communities and instream habitat. During the ecological surveys, a single composite streambed-sediment sample was collected for chemical analysis and toxicity testing. In addition, a few focused studies were done at subsets of sites, namely, measuring pesticides using small-volume automated samplers, measuring pesticides in biofilms, and sampling suspended sediments using passive samplers. This report describes the various study components and methods of the California Stream Quality Assessment, including measurements of water quality, sediment chemistry, habitat assessments, and ecological surveys, as well as procedures for sample analysis, quality assurance and quality control, and data management.

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Designing a High-Frequency Nutrient and Biogeochemical Monitoring Network for the Sacramento–San Joaquin Delta, Northern California

U.S. Geological Survey (USGS) | July 11th, 2017

Summary

This report is the third in a series of three reports that provide information about how high-frequency (HF) nutrient monitoring may be used to assess nutrient inputs and

This report is the third in a series of three reports that provide information about how high-frequency (HF) nutrient monitoring may be used to assess nutrient inputs and dynamics in the Sacramento–San Joaquin Delta, California (Delta). The purpose of this report is to provide the background, principles, and considerations for designing an HF nutrient-monitoring network for the Delta to address high-priority, nutrient-management questions. The report starts with discussion of the high-priority management questions to be addressed, continues through discussion of the questions and considerations that place demands and constraints on network design, discusses the principles applicable to network design, and concludes with the presentation of three example nutrient-monitoring network designs for the Delta. For three example network designs, we assess how they would address high-priority questions that have been identified by the Delta Regional Monitoring Program (Delta Regional Monitoring Program Technical Advisory Committee, 2015). This report, along with the other two reports of this series (Kraus and others, 2017; Downing and others, 2017), was drafted in cooperation with the Delta Regional Monitoring Program to help scientists, managers, and planners understand how HF data improve our understanding of nutrient sources and sinks, drivers, and effects in the Delta. The first report in the series (Kraus and others, 2017) provides an introduction to the reasons for and fundamental concepts behind using HF monitoring measurements, including a brief summary of nutrient status and trends in the Delta and an extensive literature review showing how and where other research and monitoring programs have used HF monitoring to improve our understanding of nutrient cycling. The report covers the various technologies available for HF nutrient monitoring and presents the different ways HF monitoring instrumentation may be used for both fixed station and spatial assessments. Finally, it presents numerous examples of how HF measurements are currently (2017) being used in the Delta to examine how nutrients and nutrient cycling are related to aquatic habitat conditions.

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Designing Monitoring Programs in an Adaptive Management Context for Regional Multiple Species Conservation Plans

U.S. Geological Survey (USGS) | January 1st, 2004

Summary

Increasing numbers of regional, multiple species conservation plans have been developed in California since the early 1990s. However, building effective monitoring and ad

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Detection and Measurement of Land Subsidence and Uplift Using Global Positioning System Surveys and Interferometric Synthetic Aperture Radar, Coachella Valley, California, 2010–17

U.S. Geological Survey (USGS) | September 3rd, 2020

Summary

Groundwater has been a major source of agricultural, recreational, municipal, and domestic supply in the Coachella Valley of California since the early 1920s. Pumpi

Groundwater has been a major source of agricultural, recreational, municipal, and domestic supply in the Coachella Valley of California since the early 1920s. Pumping of groundwater resulted in groundwater-level declines as large as 50 feet (ft) or 15 meters (m) by the late 1940s. Because of concerns that the declines could cause land subsidence, the Coachella Valley Water District (CVWD) and the U.S. Geological Survey (USGS) have cooperatively investigated subsidence in the Coachella Valley since 1996. Importation of Colorado River water to the southern Coachella Valley began in 1949, resulting in a reduction in groundwater pumping and a recovery of groundwater levels during the 1950s through the 1970s. Since the late 1970s, the demand for water in the valley increased to the point that groundwater levels again declined in response to increased pumping and, consequently, increased the potential for land subsidence caused by aquifer-system compaction. Several management actions to increase recharge or to reduce reliance on groundwater have been implemented since as early as 1973 to address overdraft in the Coachella Valley. The implementation of three particular projects has markedly improved groundwater conditions in some of the historically most overdrafted areas of the valley: (1) groundwater substitution with surface-water imports since 2006 using Colorado River water through the Mid-Valley Pipeline project, which was expanded through 2017; (2) budget-based, tiered rates since 2009; and (3) managed aquifer recharge at the Thomas E. Levy Groundwater Replenishment Facility since 2009. Global Positioning System (GPS) surveying and interferometric synthetic aperture radar (InSAR) methods were used to determine the location, extent, and magnitude of the vertical land-surface changes in the Coachella Valley during 2010–17, updating 1993–2010 information presented in previous USGS reports. The GPS measurements taken at 24 geodetic monuments in August 2010 and September 2015 indicated that the land-surface elevation was stable at 17 monuments but changed at seven monuments during the 5-year period. Subsidence ranged from 0.17 to 0.43 ±0.09 ft (52 to 132 ±28 millimeters, or mm) at three monuments, and uplift ranged from 0.11 to 0.18 ±0.09 ft (33 to 54 ±28 mm) at four monuments between 2010 and 2015. At two of the monuments that subsided, the subsidence rates decreased between 2010 and 2015 from those computed between 2005 and 2010. Data prior to 2010 were not available for the third monument that subsided; thus, the 2010–15 subsidence rate could not be compared to an earlier period. At three of the monuments that uplifted between 2010 and 2015, data collected in 2005 and 2010 indicated stability. Data prior to 2010 were not available for the fourth monument that uplifted; thus, the 2010–15 uplift rate could not be compared to an earlier period. InSAR analyses for December 28, 2014–June 27, 2017, indicated that the land surface uplifted as much as about 0.20 ft (60 mm) near the Whitewater River Groundwater Replenishment Facility in the northern Coachella Valley and subsided as much as about 0.26 ft (80 mm) in the La Quinta area and less in Palm Desert, Indian Wells, and other localized areas in the southern Coachella Valley. These areas were identified as subsidence areas in previous reports covering periods during 1993–2010. The comparison of 2014–17 subsidence rates with those derived for 1995–2010 generally indicated a substantial slowing of subsidence, however. Analyses of deformation in the northern Coachella Valley were not included in the previous reports, so a comparison to deformation during the earlier period could not be made. Water levels in wells near the subsiding geodetic monuments, in and near the three subsiding areas shown by InSAR, and throughout the valley generally indicated seasonal fluctuations and longer-term stability or rising groundwater levels since about 2010. These results mark a reversal in trends of groundwater-level declines during the preceding decades. This trend reversal provides new insights into aquifer-system mechanics. Although many areas have stopped subsiding, and a few have even uplifted, the few areas that did subside during 2010–17—albeit at a slower rate—indicate a mixed aquifer-system response. Subsidence when groundwater levels are stable or recovering indicates that residual compaction may have occurred. At the same time, coarse-grained materials and thin aquitards may have expanded as groundwater levels recovered. The continued valley-wide stabilization and recovery of groundwater levels since 2010 likely is a result of various projects designed to increase recharge or to reduce reliance on groundwater.

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Detection and measurement of land subsidence and uplift using interferometric synthetic aperture radar, San Diego, California, USA, 2016–2018

International Association of Hydrological Sciences (IAHS) | April 22nd, 2020

Summary

Land subsidence associated with groundwater-level declines is stipulated as an “undesirable effect” in California’s Sustainable Groundwater Management Act (SGMA), a

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Determination of Study Reporting Limits for Pesticide Constituent Data for the California Groundwater Ambient Monitoring and Assessment Program Priority Basin Project, 2004–2018—Part 1: National Water Quality Laboratory Schedules 2003, 2032, or 2033, and 2060

U.S. Geological Survey (USGS) | December 17th, 2019

Summary

The California Groundwater Ambient Monitoring and Assessment Program Priority Basin Project (GAMA-PBP) is a long-term cooperative project designed to assess the quality o

The California Groundwater Ambient Monitoring and Assessment Program Priority Basin Project (GAMA-PBP) is a long-term cooperative project designed to assess the quality of groundwater resources used for public and domestic drinking water supplies in the State of California, to monitor and evaluate changes to that quality, to investigate the human and natural factors controlling water quality, and to improve the availability of comprehensive groundwater quality data and information. Between May 18, 2004, and May 3, 2018, the GAMA-PBP collected 3001 groundwater samples for analysis of pesticide constituents by the U.S. Geological Survey (USGS) National Water Quality Laboratory (NWQL)(note that ‘pesticide constituents’ includes parent compounds and degradates). Of these samples, 2994 were analyzed for pesticide constituents on schedules 2003, 2032, or 2033 (65 to 84 constituents), and 840 were analyzed for pesticide constituents on schedule 2060 (58 constituents). The original dataset reported by the NWQL to the USGS National Water Information System (NWIS) database contained a total of 2,688 detections of 78 pesticide constituents and 253,825 non-detections. In this original dataset, 33 percent of the 3,001 samples analyzed had reported detections of one or more pesticide constituents. This report describes the GAMA-PBP data-quality objectives for pesticide data, the procedures used to establish study reporting limits, and use of those reporting limits to censor the data from the NWQL so that the final data published by the GAMA-PBP meet these data-quality objectives. The final GAMA-PBP dataset for samples collected from May 2004 to May 2018, after censoring, had a total of 1,632 detections of 37 pesticide constituents. In the final GAMA-PBP dataset, 25 percent of the 3,001 samples analyzed had detections of one or more pesticide constituents. The presence of pesticides in groundwater is commonly evaluated by calculating detection frequencies. Detection frequencies for pesticides are sensitive to detection limits and method performance for concentrations near those limits; therefore, the two primary data quality issues addressed in the GAMA-PBP data-quality objectives for pesticides are (1) establishing criteria for classifying data from the laboratory as detections or non-detections for the purpose of data reporting by the project and (2) accounting for changes in analytical methods or method performance over time. The GAMA-PBP addresses these issues by developing study reporting limits that are used as the boundary between detections and non-detections for the reporting of GAMA-PBP results. These reporting limits are defined from method detection limits (MDLs) provided by the NWQL, unless examination of results from laboratory set blanks (LSBs) and GAMA-PBP field blanks indicates that a higher concentration censoring limit is warranted. The GAMA-PBP selected the MDL as the primary choice for defining study reporting limits for consistency with U.S. Environmental Protection Agency (EPA) guidelines for reporting detections of pesticides and other organic constituents. A five-step procedure is used to develop study reporting limits and censor the GAMA-PBP dataset accordingly. The effect of the censoring at each step is described to provide information about the relative effect of each step on the overall censoring of the dataset. Steps 1 and 2 can be implemented at the time the data are received, whereas steps 3−5 require information accumulated over an extended period. • Step 1: Reject results that were most likely the result of specific contamination instances attributable to unusual field or laboratory conditions during sample collection or processing. Two such instances were identified, leading to rejection of 25 detections, which were assigned a data-quality indicator code of “Q” for “reviewed and rejected” in the NWIS database. • Step 2: Use the NWQL MDLs in effect at the time each sample was analyzed as the reporting limit. A total of 506 detections were censored on this basis. • Step 3: Use the maximum MDL established by the NWQL during July 2004–August 2018 (MDLmax) as the reporting limit. The rationale for using the MDLmax as the reporting limit is based primarily on the observation that the concentrations of MDLs generally increased over time. A total of 438 detections were censored on this basis. • Step 4: Use the LSBs to identify periods of greater potential laboratory contamination bias and define raised reporting limits to be used during those periods. These periods were defined by using a moving average detection frequency approach. For consistency with the NWQL procedures for defining raised reporting limits on the basis of detections in LSBs, the raised reporting limits were defined as equal to three times the highest concentration measured in an LSB during the period. A total of 25 detections in groundwater samples analyzed during periods of increased laboratory contamination bias were censored. • Step 5: Use the LSBs and field blanks to identify potential contamination bias from field or laboratory processes outside of the time periods identified in step 4. The NWQL protocols were used to define the MDLs from blanks analyzed outside of the periods identified in step 4. If an MDL defined from blanks was greater than the MDLmax, the MDL defined from blanks was used to censor the data. One constituent had a study reporting limit defined on this basis, and a total of 62 detections in groundwater samples were censored. As of 2019, the USGS NWIS database does not have the capability to store both the original value reported by the NWQL and the final value published by the GAMA-PBP that reflects application of the quality-control censoring described in this report. In the interim, while this capability is developed, the 1,031 results censored in steps 2−5 are blocked from public release in NWIS, and the GAMA-PBP has published the original and final values in a USGS data release accompanying this report. The entire GAMA-PBP final dataset for pesticide constituents on schedules 2003, 2032, or 2033, or on schedule 2060 is publicly available in that USGS data release, through the USGS GAMA-PBP public web portal, and through the California State Water Resources Control Board GAMA public groundwater information system.

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DGMETA (Version 1): Dissolved Gas Modeling and Environmental Tracer Analysis Computer Program

U.S. Geological Survey (USGS) | January 8th, 2021

Summary

DGMETA (Dissolved Gas Modeling and Environmental Tracer Analysis) is a Microsoft Excel-based computer program that is used for modeling air-water equilibrium conditions f

DGMETA (Dissolved Gas Modeling and Environmental Tracer Analysis) is a Microsoft Excel-based computer program that is used for modeling air-water equilibrium conditions from measurements of dissolved gases and for computing concentrations of environmental tracers that rely on air-water equilibrium model results. DGMETA can solve for the temperature, salinity, excess air, fractionation of gases, or pressure/elevation of water when it is equilibrated with the atmosphere. Models are calibrated inversely using one or more measurements of dissolved gases such as helium, neon, argon, krypton, xenon, and nitrogen. Excess nitrogen gas, originating from denitrification or other sources, also can be included as a fitted parameter or as a separate calculation from the dissolved gas modeling results. DGMETA uses the air-water equilibrium models to separate measured concentrations of gases and isotopes of gases into components that are used for tracing water in the environment. DGMETA calculates atmospheric dry-air mole fractions (mixing ratios) for transient atmospheric gas tracers such as chlorofluorocarbons, sulfur hexafluoride, and bromotrifluoromethane (Halon-1301); and concentrations of tritiogenic helium-3 and radiogenic helium-4, which accumulate from the decay of tritium in water and the decay of uranium and thorium in rocks, respectively. Sample data can be graphed to identify applicable models of excess air, samples that contain excess nitrogen gas, or samples that have partially degassed, for example. Monte Carlo analysis of errors associated with dissolved gas equilibrium model results can be carried through computations of environmental tracer concentrations to provide robust estimates of error. In addition, graphical routines for separating helium sources using helium isotopes are included to refine estimates of tritiogenic helium-3 when terrigenic helium from mantle or crustal sources is present in samples. Environmental tracer concentrations and their errors computed from DGMETA can be used with other programs, such as TracerLPM (Jurgens and others, 2012), to determine groundwater ages and biogeochemical reaction rates. DGMETA also produces output files in a format that meets the U.S. Geological Survey open data requirements for documentation of model inputs and outputs. DGMETA is a versatile and adaptable program that allows users to add solubility data for new gases, modify the existing set of gas solubility data, modify the default set of gases used for modeling, choose calculations based on real (non-ideal) gas behavior, and select various concentration units for data entry and results to match laboratory reports and study objectives. DGMETA comes with a set of gases widely used in hydrology and oceanography and many gases include multiple solubilities from previous work. Seventeen dissolved gases are included in the default version of the program: noble gases (helium, neon, argon, krypton, and xenon), reactive gases (nitrogen, oxygen, methane, carbon dioxide, carbon monoxide, hydrogen, and nitrous oxide), and environmental tracers (chlorofluorocarbon-11, chlorofluorocarbon-12, chlorofluorocarbon-113, sulfur hexafluoride, and Halon-1301).

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Dissolved Oxygen in South San Francisco Bay: Variability, Important Processes, and Implications for Understanding Fish Habitat

San Francisco Estuary Institute (SFEI) | October 30th, 2018

Summary

Dissolved oxygen (DO) is a key water quality parameter that is related to nutrient enrichment in estuaries around the world. In 2017-2018, the San Francisco Estuary Inst

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Distributions of waterborne pathogens in raw wastewater based on a 14-month, multi-site monitoring campaign

Water Research | February 9th, 2022

Summary

The California State Water Resources Control Board is the first regulatory body in the United States to develop statewide regulations for direct potable reuse (DPR). To s

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Draft Monitoring Special Study Plan

California State Water Resources Control Board (SWRCB) | August 15th, 2022

Summary

Delta Estuary (Bay–Delta Plan), as amended through 2006, the State Water Resources Control Board (State Water Board) set salinity objectives for the interior southern D

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Page : 18

Design and methods of the California stream quality assessment (CSQA), 2017

Designing a High-Frequency Nutrient and Biogeochemical Monitoring Network for the Sacramento–San Joaquin Delta, Northern California

Designing Monitoring Programs in an Adaptive Management Context for Regional Multiple Species Conservation Plans

Detection and Measurement of Land Subsidence and Uplift Using Global Positioning System Surveys and Interferometric Synthetic Aperture Radar, Coachella Valley, California, 2010–17

Detection and measurement of land subsidence and uplift using interferometric synthetic aperture radar, San Diego, California, USA, 2016–2018

Determination of Study Reporting Limits for Pesticide Constituent Data for the California Groundwater Ambient Monitoring and Assessment Program Priority Basin Project, 2004–2018—Part 1: National Water Quality Laboratory Schedules 2003, 2032, or 2033, and 2060

DGMETA (Version 1): Dissolved Gas Modeling and Environmental Tracer Analysis Computer Program

Dissolved Oxygen in South San Francisco Bay: Variability, Important Processes, and Implications for Understanding Fish Habitat

Distributions of waterborne pathogens in raw wastewater based on a 14-month, multi-site monitoring campaign

Draft Monitoring Special Study Plan

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