The Virginia Coastal Plain is the relatively flat region east of the fall line characterized by a wedge of coarse permeable sediments with interbedded layers of less-permeable silts and clays that thickens towards the east. The region has multiple layered aquifers, including the Potomac aquifer system.
Samuel Harrison Caldwell
Sam Caldwell joined the U.S. Geological Survey as a Pathways Student in 2018 and was converted to a hydrologist in 2019.
Sam's work is mainly centered on understanding groundwater dynamics in the Virginia Coastal Plain using groundwater level analysis, electromagnetic resistivity techniques, photogrammetry, and various scales and types of other remote sensing data.
Much of Sam's project work focuses on the Virginia Coastal Plain in Virginia Beach and the Eastern shore. He leads a groundwater level and specific conductivity monitoring network in Virginia Beach that includes an electromagnetic induction logging network to monitor for saltwater intrusion, as well as a groundwater quality sampling element. Additionally, he is responsible for an electromagnetic induction logging network on the Eastern Shore of Virginia to monitor for salwater intrusion. He also leads a water quality sampling effort in Suffolk, VA in collaboration with the Hampton Roads Sanitation District's SWIFT project monitoring how treated wastewater injected into the Potomac aqufer is affecting and moving through the nearby groundwater system. He has worked on several remote sensing and photogrammetry projects at a variety of scales with LSPIV, visual light, multispectral, and thermal infrared imagery.
Science and Products
Land Subsidence on the Virginia Coastal Plain
Land subsidence is a loss of ground elevation, often experienced as the ground slowly sinking over the course of years. In eastern Virginia, high rates of groundwater use is a major factor in the land subsidence affecting the area. The Virginia-West Virginia Water Science Center, with the help of our partners, has been monitoring land subsidence in the Virginia Coastal Plain since 1979 using a...
Virginia Eastern Shore Groundwater Resources
Informed management of groundwater resources for the Eastern Shore of Virginia depends on the availability of detailed and up-to-date scientific information. The USGS and the Virginia Department of Environmental Quality are conducting a long-term cooperative study to enhance the understanding of groundwater resources in the sole-source aquifer system beneath Accomack and Northampton counties...
Virginia Coastal Plain Aquifer systems
The Virginia Coastal Plain is the relatively flat region east of the fall line characterized by a wedge of coarse permeable sediments with interbedded layers of less-permeable silts and clays that thickens towards the east. The region has multiple layered aquifers, including the Potomac aquifer system.
Science and Products
Land Subsidence on the Virginia Coastal Plain
Land subsidence is a loss of ground elevation, often experienced as the ground slowly sinking over the course of years. In eastern Virginia, high rates of groundwater use is a major factor in the land subsidence affecting the area. The Virginia-West Virginia Water Science Center, with the help of our partners, has been monitoring land subsidence in the Virginia Coastal Plain since 1979 using a...
Virginia Eastern Shore Groundwater Resources
Informed management of groundwater resources for the Eastern Shore of Virginia depends on the availability of detailed and up-to-date scientific information. The USGS and the Virginia Department of Environmental Quality are conducting a long-term cooperative study to enhance the understanding of groundwater resources in the sole-source aquifer system beneath Accomack and Northampton counties...
Virginia Coastal Plain Aquifer systems
The Virginia Coastal Plain is the relatively flat region east of the fall line characterized by a wedge of coarse permeable sediments with interbedded layers of less-permeable silts and clays that thickens towards the east. The region has multiple layered aquifers, including the Potomac aquifer system.
The Virginia Coastal Plain is the relatively flat region east of the fall line characterized by a wedge of coarse permeable sediments with interbedded layers of less-permeable silts and clays that thickens towards the east. The region has multiple layered aquifers, including the Potomac aquifer system.