Andrew J Long
Andy Long has more than 30 years of experience assessing groundwater flow and transport through numerical and conceptual modeling, analyzing ambient and injected tracers, and geophysical methods.
Science and Products
Filter Total Items: 13
Hydrochemical Analysis of Groundwater in Jewel Cave National Monument
The Issue: The park’s landscape and geomorphology is characterized as a carbonate karst environment, with sinking streams and fast connections between surface water and groundwater, resulting in high vulnerability of contamination to groundwater. Now that subterranean lakes have been discovered in Jewel Cave, understanding the groundwater connection of the lakes therein to the lakes in nearby Wind...
Assess the utility of a regional aquifer system groundwater model to inform the USGS National Hydrologic Model
The Issue: In Washington State, groundwater (GW) inflow to streams, or baseflow, is essential for maintaining aquatic habitats, and for out-of-stream uses such as irrigated agriculture during the typically dry summers. However, the National Hydrologic Model (NHM) currently is most suited to predicting total daily streamflow. This project aims to assess the NHM’s performance in simulating baseflow...
Walla Walla River Basin groundwater-flow system, Oregon-Washington
The Issue: Decades of declining groundwater levels in the Walla Walla River Basin (WWRB), which spans Oregon and Washington, are affecting instream flows for threatened and culturally important fish populations and water availability for competing interests across state lines. The public and state resource management agencies have begun implementing efforts to stabilize groundwater levels and...
Williston and Powder River Basins Groundwater Availability Study
The development of two nationally important energy-producing areas, the Williston structural basin (containing the Bakken Formation) and Powder River structural basin, provide a critical opportunity to study the water-energy nexus within a groundwater context. Large volumes of water are needed for energy development in these basins. The hydraulically connected aquifers in the regional glacial...
Keyport Groundwater Model
The Issue: Chlorinated volatile organic compounds have impacted groundwater beneath a former 9-acre landfill at OU 1 of the Naval Base Kitsap Keyport, Washington. The landfill is adjacent to tidal flats that are an extension of Liberty and Dogfish Bays and was the primary disposal area for domestic and industrial waste generated by NBK Keyport from the 1930s through 1973. The Navy needs a detailed...
Quincy Groundwater
The Issue: Since 1952, water diverted from the Columbia River for irrigation in parts of the Quincy Subarea in eastern Washington has resulted in rising groundwater levels and increased groundwater flows and storage. Managers of groundwater in the area need a better understanding of the flow system before and after the start of irrigation. How the USGS will help: In a joint effort with Washington...
RRAWFLOW: Rainfall-Response Aquifer and Watershed Flow Model
RRAWFLOW: Rainfall-Response Aquifer and Watershed Flow Model
Groundwater Flow, Quality, and Mixing in the Wind Cave National Park Area, South Dakota
Project Period: 2007-2010 Cooperator: National Park Service Project Chief: Andrew Long
Kitsap Groundwater Model
The Issue: Groundwater provides a major source of drinking water for the population of the Kitsap Peninsula. Consequently, as the population grows, so does the demand for groundwater. However, the quantity of usable groundwater is limited, largely because the Peninsula is bounded by seawater and the potential for water-level declines and seawater intrusion increases as groundwater usage increases...
Pasco Groundwater Storage
The Issue: Since 1952 water diverted from the Columbia River has been used to irrigate parts of the Pasco basin in eastern Washington. As a result of the surface-water irrigation, groundwater levels generally have risen in the area. The increases in groundwater fluxes and groundwater in storage have created a need to better understand the flow system before and after the start of irrigation to...
Chimacum GW Model
Projected increases in population and development in northeastern Jefferson County, Washington, are expected to lead to increased groundwater withdrawals in the Chimacum Creek Basin. Changes in land use and climate could reduce groundwater recharge, thereby reducing groundwater available for drinking and for baseflow to streams that host endangered fish species. The USGS is developing quantitative...
Yakima River Basin
The Yakima River flows 215 miles from the outlet of Keechelus Lake in the central Washington Cascades southeasterly to the Columbia River, draining an area of 6,155 square miles. The Yakima River Basin is one of the most intensively irrigated areas in the United States. Population in the Yakima River Basin was about 238,000 in 1990. Increasing demands for water for municipal, fisheries...
Science and Products
Filter Total Items: 13
Hydrochemical Analysis of Groundwater in Jewel Cave National Monument
The Issue: The park’s landscape and geomorphology is characterized as a carbonate karst environment, with sinking streams and fast connections between surface water and groundwater, resulting in high vulnerability of contamination to groundwater. Now that subterranean lakes have been discovered in Jewel Cave, understanding the groundwater connection of the lakes therein to the lakes in nearby Wind...
Assess the utility of a regional aquifer system groundwater model to inform the USGS National Hydrologic Model
The Issue: In Washington State, groundwater (GW) inflow to streams, or baseflow, is essential for maintaining aquatic habitats, and for out-of-stream uses such as irrigated agriculture during the typically dry summers. However, the National Hydrologic Model (NHM) currently is most suited to predicting total daily streamflow. This project aims to assess the NHM’s performance in simulating baseflow...
Walla Walla River Basin groundwater-flow system, Oregon-Washington
The Issue: Decades of declining groundwater levels in the Walla Walla River Basin (WWRB), which spans Oregon and Washington, are affecting instream flows for threatened and culturally important fish populations and water availability for competing interests across state lines. The public and state resource management agencies have begun implementing efforts to stabilize groundwater levels and...
Williston and Powder River Basins Groundwater Availability Study
The development of two nationally important energy-producing areas, the Williston structural basin (containing the Bakken Formation) and Powder River structural basin, provide a critical opportunity to study the water-energy nexus within a groundwater context. Large volumes of water are needed for energy development in these basins. The hydraulically connected aquifers in the regional glacial...
Keyport Groundwater Model
The Issue: Chlorinated volatile organic compounds have impacted groundwater beneath a former 9-acre landfill at OU 1 of the Naval Base Kitsap Keyport, Washington. The landfill is adjacent to tidal flats that are an extension of Liberty and Dogfish Bays and was the primary disposal area for domestic and industrial waste generated by NBK Keyport from the 1930s through 1973. The Navy needs a detailed...
Quincy Groundwater
The Issue: Since 1952, water diverted from the Columbia River for irrigation in parts of the Quincy Subarea in eastern Washington has resulted in rising groundwater levels and increased groundwater flows and storage. Managers of groundwater in the area need a better understanding of the flow system before and after the start of irrigation. How the USGS will help: In a joint effort with Washington...
RRAWFLOW: Rainfall-Response Aquifer and Watershed Flow Model
RRAWFLOW: Rainfall-Response Aquifer and Watershed Flow Model
Groundwater Flow, Quality, and Mixing in the Wind Cave National Park Area, South Dakota
Project Period: 2007-2010 Cooperator: National Park Service Project Chief: Andrew Long
Kitsap Groundwater Model
The Issue: Groundwater provides a major source of drinking water for the population of the Kitsap Peninsula. Consequently, as the population grows, so does the demand for groundwater. However, the quantity of usable groundwater is limited, largely because the Peninsula is bounded by seawater and the potential for water-level declines and seawater intrusion increases as groundwater usage increases...
Pasco Groundwater Storage
The Issue: Since 1952 water diverted from the Columbia River has been used to irrigate parts of the Pasco basin in eastern Washington. As a result of the surface-water irrigation, groundwater levels generally have risen in the area. The increases in groundwater fluxes and groundwater in storage have created a need to better understand the flow system before and after the start of irrigation to...
Chimacum GW Model
Projected increases in population and development in northeastern Jefferson County, Washington, are expected to lead to increased groundwater withdrawals in the Chimacum Creek Basin. Changes in land use and climate could reduce groundwater recharge, thereby reducing groundwater available for drinking and for baseflow to streams that host endangered fish species. The USGS is developing quantitative...
Yakima River Basin
The Yakima River flows 215 miles from the outlet of Keechelus Lake in the central Washington Cascades southeasterly to the Columbia River, draining an area of 6,155 square miles. The Yakima River Basin is one of the most intensively irrigated areas in the United States. Population in the Yakima River Basin was about 238,000 in 1990. Increasing demands for water for municipal, fisheries...