Preprints
Filtering by Subject: Hydrology
Decadal Trends in the Quality of Groundwater Used for Public Drinking-Water Supply in California, 2004–2023, California Groundwater Ambient Monitoring and Assessment Program, Priority Basin Project
Published: 2026-02-25
Subjects: Earth Sciences, Hydrology
This study provides a comprehensive assessment of decadal changes in the quality of groundwater used for public drinking-water supply at 444 monitoring sites across California during 2004–2023. We assessed decadal step trends in groundwater quality for 145 water-quality constituents and geochemical indicators statewide and across geographic and land-use based network groups. We evaluated the [...]
Data-driven control reveals distributed flood adaptation priorities across large river networks under climate change
Published: 2026-02-24
Subjects: Civil and Environmental Engineering, Dynamical Systems, Hydrology, Water Resource Management
Distributed flood adaptation requires knowing where in a river network attenuation effort should concentrate and how much each reach requires, but the spatial coupling, scenario dependence, and high dimensionality of real drainage networks have kept these requirements largely unresolved. We combine data-driven dynamics learning, reduced-order modeling, and optimal control theory into a diagnostic [...]
Biochar granulation and particle size influence hydrological performance of green roof substrates
Published: 2026-02-20
Subjects: Civil and Environmental Engineering, Environmental Monitoring, Hydrology, Materials Science and Engineering, Sustainability, Water Resource Management
Green roofs are increasingly being implemented in cities to improve stormwater management and provide additional ecosystem services. Biochar, a carbon-rich material derived from pyrolyzed biomass, has emerged as a promising substrate additive to improve hydrological performance of green roofs; however, unprocessed biochar is susceptible to erosion loss. Biochar granulation and particle size [...]
Assessing and Correcting Bias in Gridded Reference Evapotranspiration over Agricultural Lands Across the Contiguous United States
Published: 2026-02-19
Subjects: Applied Statistics, Climate, Environmental Monitoring, Geographic Information Sciences, Hydrology, Multivariate Analysis, Remote Sensing, Spatial Science, Water Resource Management
Gridded reference evapotranspiration (ETo) data are widely used for agricultural water management and remote sensing ET (RSET) models, but biases can arise in agricultural regions where coarse-resolution meteorological inputs fail to capture local microclimates. We investigated biases in the gridMET ETo product across irrigated agricultural areas of the contiguous United States (CONUS) by [...]
Channel Change and Sediment Transport in the Puyallup River Watershed through 2022
Published: 2026-02-18
Subjects: Earth Sciences, Geomorphology, Hydrology, Physical Sciences and Mathematics, Water Resource Management
The Puyallup River drains a 990 square mile watershed in western Washington, with headwaters on the glacier-covered flanks of Mount Rainier. Major tributaries include the White, Carbon, and Mowich Rivers. In the levee-confined reaches of the lower watershed, loss of flood conveyance due to sand and gravel deposition has been a chronic issue. Over much of the 20th century, flood conveyance was [...]
Multi-Sensor Fusion of Sentinel-2 Imagery and ICESat-2 Satellite Laser Bathymetry for Benthic Habitat Classification in Key Largo, Florida Keys
Published: 2026-02-14
Subjects: Earth Sciences, Geophysics and Seismology, Hydrology, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Multispectral imagery has traditionally been used to classify benthic habitats; however, many challenges exist when using this method alone including the overlap of spectral signatures among habitat types, and the loss of signal due to water depth in coastal areas. The authors propose an innovative method that combines multispectral imagery from Sentinel-2 (Tile 17RNJ, January 30, 2024) with [...]
Two-thirds of global coastline affected by climate-driven saline groundwater intrusion by end of century, reaching far inland by 2300
Published: 2026-02-13
Subjects: Earth Sciences, Hydrology, Physical Sciences and Mathematics
Fresh groundwater is a vital resource along global coastlines where already over a third of the world’s population lives. Saline groundwater intrusion, driven by sea-level rise, groundwater abstraction, and reduced recharge, threatens the potability of coastal groundwater. Yet, the global potential for intrusion remains uncertain. Using a global groundwater model, we assess climate-driven saline [...]
Multiple-Well Monitoring Site Adjacent to the Midway- Sunset and Buena Vista Oil Fields, Kern County, California
Published: 2026-02-12
Subjects: Earth Sciences, Geochemistry, Geology, Hydrology, Physical Sciences and Mathematics
Groundwater quality in and around oil fields in the Southern San Joaquin Valley is of interest to many California residents that rely heavily on groundwater for domestic, commercial, and agricultural use. To help assess the effects of historical oil-field activities and natural geologic sources on groundwater near the southwest margins of the Kern County Groundwater Subbasin, a multiple-well [...]
Widespread reliance of rainfed crops on upwind irrigated agriculture in India
Published: 2026-02-03
Subjects: Agriculture, Atmospheric Sciences, Climate, Hydrology, Sustainability, Water Resource Management
Rainfed crops account for approximately 40% of India’s food production and support 60% of its livestock. Although linked to oceanic monsoon rainfall, their productivity also depends on terrestrial evaporation, particularly in the non-monsoon season. However, the degree to which rainfed crops also rely on moisture sourced from upwind irrigated areas, remains largely unknown. Using a combination of [...]
A Benchmark Dataset of Agricultural Weather Stations over the Contiguous United States for Evapotranspiration Applications
Published: 2026-01-17
Subjects: Environmental Monitoring, Environmental Studies, Geographic Information Sciences, Hydrology, Water Resource Management
Agricultural weather data are fundamental for the accurate estimate of evapotranspiration (ET), irrigation scheduling, and water-use accounting. In particular, reference ET provides a standardized atmospheric demand for water loss from a hypothetical well-watered grass (ETo) or alfalfa (ETr); however, weather stations may not adequately represent such climatic conditions. Weather data commonly [...]
Benchmarking analog and ensemble-based seasonal forecasting strategies for water management in the Upper Rio Grande basin
Published: 2026-01-17
Subjects: Earth Sciences, Hydrology
In the southwestern US, declining runoff efficiencies driven by a warming climate have undermined the skill of seasonal water supply forecast (WSF) methods used for reservoir management by local to federal agencies. Seasonal water allocations are often based on deterministic inflow sequences, derived by matching historical streamflow traces (analogs) to statistical WSF volumes; yet model-based [...]
Use of Low Impact Development Systems to Enhance Recharge using Stormwater in a Heavily Groundwater-Depleted Region of the Gulf Coast Aquifer
Published: 2026-01-17
Subjects: Civil Engineering, Environmental Engineering, Hydrology, Sustainability, Water Resource Management
Water resources in the Houston Metropolitan Area, otherwise known as Greater Houston, have been under enormous stress for decades due to an increase in population and uncertain climate conditions. Rapid urbanization has also increased impervious cover, leading to excess stormwater runoff. Implementing managed aquifer recharge (MAR) through the use of low impact development (LID) strategies can [...]
Global sediment transport intermittency is set by river planform
Published: 2026-01-14
Subjects: Earth Sciences, Geomorphology, Hydrology, Sedimentology
Patterns of water and sediment flux in rivers are key to understanding landscape responses to environmental change. Quantifying water intermittency in rivers (from perennial to ephemeral) provides vital context for interpreting long-term hydrographs and flood frequency, yet controls on corresponding sediment intermittency are poorly understood due to measurement challenges. We present the first [...]
Digging Through the Trash: An Investigation into Hidden Sources of Information in GNSS-R Observations
Published: 2026-01-09
Subjects: Hydrology
Interpreting remote sensing data sometimes feels like a dark art. We aim to assign a single meaning to ambiguous signals that were actually affected by a slew of unique conditions. And NASA's Cyclone Global Navigation Satellite System (CYGNSS) data are no exception. When we observe an increase in CYGNSS surface reflectivity, we most often attribute it to either an increase in soil moisture or in [...]
VRFIS: An Immersive Framework for Real-Time Flood Monitoring, Visualization, and Interactive Environmental Analysis
Published: 2025-12-31
Subjects: Environmental Engineering, Environmental Monitoring, Graphics and Human Computer Interfaces, Hydrology
The rapid evolution of Mixed Reality (MR) technologies, particularly Virtual Reality (VR), offers powerful new means of visualizing and interacting with geographic and environmental data. This paper presents Virtual Reality Flood Information System (VRFIS), an immersive information platform developed using Unreal Engine 5 and Google Photo Realistic 3D Tiles to enable real-time exploration of [...]