Stefan Voss
Stefan Voss is a Hydrologist at the California Water Science Center.
Science and Products
Data for Per- and Polyfluoroalkyl Substances (PFAS) in groundwater samples collected by the California Groundwater Ambient Monitoring and Assessment Priority Basin Project, 2019-2023
The California Groundwater Ambient Monitoring and Assessment Program Priority Basin Project (GAMA-PBP) analyzed for per-and polyfluoroalkyl substances (PFAS) in groundwater samples collected from domestic and public drinking water supply wells in California. GAMA-PBP is a cooperative program between the U.S. Geological Survey and the California State Water Resources Control Board.
This data relea
Sucralose Concentrations in Groundwater in California's Sacramento Valley Shallow Aquifer System
This data release comprises a set of environmental sucralose occurrence data in the Sacramento area. Groundwater samples were collected throughout the Sacramento Valley as part of the California Groundwater Ambient Monitoring and Assessment Program Priority Basin Project study in the Sacramento area. These water samples were analyzed for sucralose by chemical derivatization followed by gas chromat
Predictions of groundwater PFAS occurrence at drinking water supply depths in the United States
Per- and polyfluoroalkyl substances (PFAS), known colloquially as “forever chemicals”, have been associated with adverse human health effects and have contaminated drinking water supplies across the United States owing to their long-term and widespread use. People in the United States may unknowingly be drinking water that contains PFAS because of a lack of systematic analysis, particularly in dom
Authors
Andrea K. Tokranov, Katherine Marie Ransom, Laura M. Bexfield, Bruce D. Lindsey, Elise Watson, Danielle Dupuy, Paul Stackelberg, Miranda S. Fram, Stefan Voss, James A. Kingsbury, Bryant Jurgens, Kelly Smalling, Paul M. Bradley
Modeling the dynamic penetration depth of post-1950s water in unconfined aquifers using environmental tracers: Central Valley, California
The penetration depth of post-1950s recharge (D-1950) in aquifers is a marker that is frequently used to identify groundwater that is susceptible to anthropogenic contamination. Here, we compute D-1950 values at wells, interpolate them in space, and project them across time to map the moving front of modern recharge in four dimensions in the Central Valley aquifer system, California, USA. Tracers
Authors
Kirsten Faulkner, Bryant Jurgens, Stefan Voss, Danielle Dupuy, Zeno Levy
Critical aquifer overdraft accelerates degradation of groundwater quality in California’s Central Valley during drought
Drought-induced pumpage has precipitated dramatic groundwater-level declines in California’s Central Valley over the past 30 years, but the impacts of aquifer overdraft on water quality are poorly understood. This study coupled over 160,000 measurements of nitrate from ∼6,000 public-supply wells with a 30-year reconstruction of groundwater levels throughout the Central Valley to evaluate dynamic r
Authors
Zeno Levy, Bryant Jurgens, Karen R. Burow, Stefan Voss, Kirsten Faulkner, Jose Alfredo Arroyo-Lopez, Miranda S. Fram
Delineation of spatial extent, depth, thickness, and potential volume of aquifers used for domestic and public water-supply in the Central Valley, California
Identification of the groundwater resources used for drinking-water supplies is essential for the design of strategies to manage those resources. In this study, the spatial extent, depths, thicknesses, and volumes of groundwater aquifers used for domestic and public drinking-water supply were estimated from locations and well-construction data from 11,725 domestic-supply wells and 2,376 public-sup
Authors
Stefan Voss, Bryant C. Jurgens, Miranda S. Fram, George L. Bennett
Quantification of sucralose in groundwater well drinking water by silylation derivatization and gas chromatography-mass spectrometry
Sucralose is an increasingly popular artificial sweetener and has been found in the environment in groundwater, surface water, and wastewater treatment plant effluent. Its chemical properties make it strongly recalcitrant in the environment and it has been used as a conservative tracer of human wastewater in recent years. Most current methods of sucralose analysis use high performance liquid chrom
Authors
Stefan Voss, Elisabeth Newman, Justin P Miller-Schulze
CalPUR-LUE
Estimating High Resolution Multi-Cropped Irrigated Land Use Using a Pesticide Use Reporting Database in California
Estimating the amount of water needed for agriculture is vital for food and water security. These estimates rely on maps of crop type and acreage that have limited ground-truthing or represent multiple years or regional cropping patterns. In regions where crops change frequently or m
Science and Products
Data for Per- and Polyfluoroalkyl Substances (PFAS) in groundwater samples collected by the California Groundwater Ambient Monitoring and Assessment Priority Basin Project, 2019-2023
The California Groundwater Ambient Monitoring and Assessment Program Priority Basin Project (GAMA-PBP) analyzed for per-and polyfluoroalkyl substances (PFAS) in groundwater samples collected from domestic and public drinking water supply wells in California. GAMA-PBP is a cooperative program between the U.S. Geological Survey and the California State Water Resources Control Board.
This data relea
Sucralose Concentrations in Groundwater in California's Sacramento Valley Shallow Aquifer System
This data release comprises a set of environmental sucralose occurrence data in the Sacramento area. Groundwater samples were collected throughout the Sacramento Valley as part of the California Groundwater Ambient Monitoring and Assessment Program Priority Basin Project study in the Sacramento area. These water samples were analyzed for sucralose by chemical derivatization followed by gas chromat
Predictions of groundwater PFAS occurrence at drinking water supply depths in the United States
Per- and polyfluoroalkyl substances (PFAS), known colloquially as “forever chemicals”, have been associated with adverse human health effects and have contaminated drinking water supplies across the United States owing to their long-term and widespread use. People in the United States may unknowingly be drinking water that contains PFAS because of a lack of systematic analysis, particularly in dom
Authors
Andrea K. Tokranov, Katherine Marie Ransom, Laura M. Bexfield, Bruce D. Lindsey, Elise Watson, Danielle Dupuy, Paul Stackelberg, Miranda S. Fram, Stefan Voss, James A. Kingsbury, Bryant Jurgens, Kelly Smalling, Paul M. Bradley
Modeling the dynamic penetration depth of post-1950s water in unconfined aquifers using environmental tracers: Central Valley, California
The penetration depth of post-1950s recharge (D-1950) in aquifers is a marker that is frequently used to identify groundwater that is susceptible to anthropogenic contamination. Here, we compute D-1950 values at wells, interpolate them in space, and project them across time to map the moving front of modern recharge in four dimensions in the Central Valley aquifer system, California, USA. Tracers
Authors
Kirsten Faulkner, Bryant Jurgens, Stefan Voss, Danielle Dupuy, Zeno Levy
Critical aquifer overdraft accelerates degradation of groundwater quality in California’s Central Valley during drought
Drought-induced pumpage has precipitated dramatic groundwater-level declines in California’s Central Valley over the past 30 years, but the impacts of aquifer overdraft on water quality are poorly understood. This study coupled over 160,000 measurements of nitrate from ∼6,000 public-supply wells with a 30-year reconstruction of groundwater levels throughout the Central Valley to evaluate dynamic r
Authors
Zeno Levy, Bryant Jurgens, Karen R. Burow, Stefan Voss, Kirsten Faulkner, Jose Alfredo Arroyo-Lopez, Miranda S. Fram
Delineation of spatial extent, depth, thickness, and potential volume of aquifers used for domestic and public water-supply in the Central Valley, California
Identification of the groundwater resources used for drinking-water supplies is essential for the design of strategies to manage those resources. In this study, the spatial extent, depths, thicknesses, and volumes of groundwater aquifers used for domestic and public drinking-water supply were estimated from locations and well-construction data from 11,725 domestic-supply wells and 2,376 public-sup
Authors
Stefan Voss, Bryant C. Jurgens, Miranda S. Fram, George L. Bennett
Quantification of sucralose in groundwater well drinking water by silylation derivatization and gas chromatography-mass spectrometry
Sucralose is an increasingly popular artificial sweetener and has been found in the environment in groundwater, surface water, and wastewater treatment plant effluent. Its chemical properties make it strongly recalcitrant in the environment and it has been used as a conservative tracer of human wastewater in recent years. Most current methods of sucralose analysis use high performance liquid chrom
Authors
Stefan Voss, Elisabeth Newman, Justin P Miller-Schulze
CalPUR-LUE
Estimating High Resolution Multi-Cropped Irrigated Land Use Using a Pesticide Use Reporting Database in California
Estimating the amount of water needed for agriculture is vital for food and water security. These estimates rely on maps of crop type and acreage that have limited ground-truthing or represent multiple years or regional cropping patterns. In regions where crops change frequently or m