Toby Welborn
Biography
Toby Welborn has been with the U.S. Geological Survey since 1999. In that time, he has served as a Geographer, the Spatial Analysis Unit section lead for the Nevada Water Science Center, and most recently the Geospatial Science Section Chief for the Oklahoma-Texas Water Science Center. In those roles he has provided technical expertise and guidance to stakeholders, cooperators, and colleagues and worked closely with a talented team of developers, geographers and hydrologists contributing to ongoing research within the USGS to produce innovative geospatial and data solutions for hydrologic and spatial analyses and visualizations.
Science and Products
Building a framework to compute continuous grids of basin characteristics for the conterminous United States
The proposed work will create a seamless pilot dataset of continuous basin characteristics (for example upstream average precipitation, elevation, or dominant land cover type) for the conterminous United States. Basin characteristic data are necessary for training or parameterizing statistical, machine learning, and physical models, and for making predictions across the landscape, particularly...
Nevada Flood Chronology
The lowest annual average precipitation and one of the fastest growing populations in the United States contribute to a tendency for both the general public and land-use planners to underestimate flood hazards in Nevada, despite historical evidence of frequent flooding.
Geospatial Data, Tabular Data, and Surface-Water Model Archive for Delineation of Flood-Inundation Areas in Grapevine Canyon Near Scotty's Castle, Death Valley National Park, California
This U.S. Geological Survey data release consists of a polygon geospatial dataset representing estimated flood-inundation areas in Grapevine Canyon near Scotty's Castle, Death Valley National Park, and the data acquired and processed to support the delineation of those areas. Supporting datasets include topographic survey data collected by global navigation satellite system (GNSS) and t
Air, plant, and unsaturated-zone tritium and plant-metrics data, Amargosa Desert Research Site, Nye County, Nevada, 2012–2016
These data comprise air, plant (creosote bush, Larrea tridentata), and unsaturated-zone tritium measurements and plant metrics collected during 2012 to 2016 from three sampling areas at the Amargosa Desert Research Site (ADRS) near Beatty, Nevada: (1) within a low-level radioactive waste facility, (2) buffer area adjacent to the waste facility, and (3) reference
Evapotranspiration units and potential areas of groundwater discharge delineated July 20–24, 2009 in the upper Humboldt River Basin, northeastern Nevada
The data set consists of 2 separate items for the upper Humboldt River Basin:
1. evapotranspiration units
2. potential areas of groundwater discharge
Irrigated Acreage Delineated from Landsat-Derived Maximum Normalized Difference Vegetation Index (NDVI) 1975-2010, Walker River Basin Nevada and California
These data represent the extent and spatial distribution of irrigated acreage delineated from maximum Normalized Difference Vegetation Index (NDVI) derived from Landsat scenes in the Walker River Basin, California and Nevada, at five-year intervals from 1975-2010.
Depth-to-water area polygons, isopleths showing mean annual runoff, 1912-1963, and water-level altitude contours for the Humboldt River Basin, Nevada
This data set consists of 1:500,000-scale isopleths showing mean annual runoff, 1912-1963, for the Humboldt River Basin, Nevada as published in the Nevada Department of Conservation and Natural Resources Water Resources Bulletin 32 titled "Hydrologic reconnaissance of the Humboldt River basin, Nevada", 1966.
Groundwater Sites Evaluated to Assess The Vulnerability of Public Supply Wells To Increasing Arsenic Concentrations In Southeastern Carson Valley, Douglas County, Nevada
This data set provides a spatial and temporal assessment of available chemical and physical data from local, county, state, and federal databases for the Carson Valley, near Minden, Nevada.
Groundwater-level and groundwater-level change contours for the Lahontan Valley shallow aquifer near Fallon, Nevada, 2012
USGS data release of two geospatial datasets from Lahontan Valley near Fallon, NV: contours representing water levels based on depth-to-groundwater measurements made at 98 wells in July 2012 and contours representing water level change in the shallow aquifer (1992-2012) based on depth-to-groundwater measurements made in 73 wells in 1992 and 2012, with limited measurements made in 2013.
Delineation of flood-inundation areas in Grapevine Canyon near Scotty’s Castle, Death Valley National Park, California
On October 18, 2015, a large flood caused considerable damage in Grapevine Canyon near Death Valley Scotty Historic District, in Death Valley National Park, California. Significant channel changes had limited the applicability of previously created flood-inundation maps to current conditions. Predicted flood-inundation maps for Scotty’s Castle...
Morris, Christopher M.; Welborn, Toby L.; Minear, J. Toby
Flood-inundation mapping of a steep, gravel desert stream in Death Valley National Park, California
In desert landscapes, flooding can result in dramatic changes to streams. However, the frequency, magnitude, and geomorphic effects of floods in such environments are less understood compared to wetter environments (Tooth, 2000). In desert landscapes, steep slopes and sparse vegetation result in runoff and flashy flood peaks, often lasting for...
Morris, Christopher M.; Welborn, Toby L.
Characterization of peak streamflows and flood inundation of selected areas in southeastern Texas and southwestern Louisiana from the August and September 2017 flood resulting from Hurricane Harvey
Hurricane Harvey made landfall near Rockport, Texas, on August 25, 2017, as a Category 4 hurricane with wind gusts exceeding 150 miles per hour. As Harvey moved inland, the forward motion of the storm slowed down and produced tremendous rainfall amounts over southeastern Texas, with 8-day rainfall amounts exceeding 60 inches in some locations,...
Watson, Kara M.; Harwell, Glenn R.; Wallace, David S.; Welborn, Toby L.; Stengel, Victoria G.; McDowell, Jeremy S.
Groundwater-level change and evaluation of simulated water levels for irrigated areas in Lahontan Valley, Churchill County, west-central Nevada, 1992 to 2012
The acquisition and transfer of water rights to wetland areas of Lahontan Valley, Nevada, has caused concern over the potential effects on shallow aquifer water levels. In 1992, water levels in Lahontan Valley were measured to construct a water-table map of the shallow aquifer prior to the effects of water-right transfers mandated by the Fallon...
Smith, David W.; Buto, Susan G.; Welborn, Toby L. Soil, plant, and terrain effects on natural perchlorate distribution in a desert landscape
Perchlorate (ClO4−) is a contaminant that occurs naturally throughout the world, but little is known about its distribution and interactions in terrestrial ecosystems. The objectives of this Amargosa Desert, Nevada study were to determine (i) the local-scale distribution of shallow-soil (0–30 cm) ClO4− with respect to shrub proximity (far and near...
Andraski, Brian J.; Jackson, W.A.; Welborn, Toby L.; Böhlke, John Karl; Sevanthi, Ritesh; Stonestrom, David A. ARkStorm@Tahoe: Stakeholder perspectives on vulnerabilities and preparedness for an extreme storm event in the greater Lake Tahoe, Reno, and Carson City region
Atmospheric rivers (ARs) are strongly linked to extreme winter precipitation events in the Western U.S., accounting for 80 percent of extreme floods in the Sierra Nevada and surrounding lowlands. In 2010, the U.S. Geological Survey developed the ARkStorm extreme storm scenario for California to quantify risks from extreme winter storms and to...
Albano, Christine M.; Cox, Dale A.; Dettinger, Michael D.; Shaller, Kevin; Welborn, Toby L.; McCarthy, Maureen
The distribution and modeling of nitrate transport in the Carson Valley alluvial aquifer, Douglas County, Nevada
Residents of Carson Valley in Douglas County, Nevada, rely on groundwater from an alluvial aquifer for domestic use and agricultural irrigation. Since the 1970s, there has been a rapid increase in population in several parts of the valley that rely on domestic wells for drinking water and septic systems for treatment of household waste. As a...
Naranjo, Ramon C.; Welborn, Toby L.; Rosen, Michael R.
Phreatophytic land-cover map of the northern and central Great Basin Ecoregion: California, Idaho, Nevada, Utah, Oregon, and Wyoming
Increasing water use and changing climate in the Great Basin of the western United States are likely affecting the distribution of phreatophytic vegetation in the region. Phreatophytic plant communities that depend on groundwater are susceptible to natural and anthropogenic changes to hydrologic flow systems. The purpose of this report is to...
Mathie, Amy M.; Welborn, Toby L.; Susong, David D.; Tumbusch, Mary L.
Hydrogeology of the Lake Tahoe Basin, California and Nevada
Ground water in the Lake Tahoe basin is the primary source of domestic and municipal water supply and an important source of inflow to Lake Tahoe. Over the past 30-40 years, Federal, State, and local agencies, and research institutions have collected hydrologic data to quantify the ground-water resources in the Lake Tahoe basin. These data are...
Plume, Russell W.; Tumbusch, Mary L.; Welborn, Toby L. Hydrologic and Water-Quality Responses in Shallow Ground Water Receiving Stormwater Runoff and Potential Transport of Contaminants to Lake Tahoe, California and Nevada, 2005-07
Clarity of Lake Tahoe, California and Nevada has been decreasing due to inflows of sediment and nutrients associated with stormwater runoff. Detention basins are considered effective best management practices for mitigation of suspended sediment and nutrients associated with runoff, but effects of infiltrated stormwater on shallow ground water are...
Green, Jena M.; Thodal, Carl E.; Welborn, Toby L. Irrigated Acreage Within the Basin and Range Carbonate-Rock Aquifer System, White Pine County, Nevada, and Adjacent Areas in Nevada and Utah
Accurate delineations of irrigated acreage are needed for the development of water-use estimates and in determining water-budget calculations for the Basin and Range carbonate-rock aquifer system (BARCAS) study. Irrigated acreage is estimated routinely for only a few basins in the study area. Satellite imagery from the Landsat Thematic Mapper and...
Welborn, Toby L.; Moreo, Michael T. Mapping Evapotranspiration Units in the Basin and Range Carbonate-Rock Aquifer System, White Pine County, Nevada, and Adjacent Areas in Nevada and Utah
Accurate estimates of ground-water discharge are crucial in the development of a water budget for the Basin and Range carbonate-rock aquifer system study area. One common method used throughout the southwestern United States is to estimate ground-water discharge from evapotranspiration (ET). ET is a process by which water from the Earth's surface...
Smith, J. LaRue; Laczniak, Randell J.; Moreo, Michael T.; Welborn, Toby L.
Newly Released Web-based Tool Aims to Provide Real-time Walker River Basin Hydrologic Data
The newly released web-based Walker Basin Hydro Mapper aims to provide real-time visualization of streamflow, and waterbody stage and volume in the Walker River Basin.