Kalle L Jahn
Kalle Jahn is a Physical Scientist with the New York Water Science Center.
I investigate physical and chemical controls on subsurface water flow and solute transport, with the ultimate goal of supporting informed water resource management decisions. I use numerical modeling techniques to quantify water and solute fluxes and characterize bedrock/soil hydraulic and chemical properties. I am interested the fate of both legacy and emerging contaminants, particularly per- and polyfluoroalkyl substances (PFAS). Currently, I'm studying the groundwater systems of Long Island, NY, including the past and future evolution of the island's freshwater-saltwater interface and island-wide nitrogen transport from 1900-present.
Science and Products
Groundwater Sustainability of the Long Island Aquifer System
The U.S. Geological Survey (USGS) has partnered with the New York State Department of Environmental Conservation (NYSDEC) to conduct a comprehensive study of the Long Island aquifer system. The major findings of this investigation include: The location of the boundary between fresh and salty groundwater is much closer to the shoreline than previously thought. The historical onshore saltwater...
Groundwater Flow Modeling - Long Island, New York
Numerical models provide a means to synthesize existing hydrogeologic information into an internally consistent mathematical representation of a real system or process, and thus are useful tools for testing and improving conceptual models or hypotheses of groundwater flow systems. The goal of this effort is to develop a regional model for the Long Island aquifer system to simulate changes in water...
The Use of Solute-transport Methods to Estimate Time-varying Nitrogen Loading Rates to the Peconic Estuary Resulting from Wastewater and Fertilizer Inputs to Groundwater in Suffolk County, New York (Peconic Solute Transport)
Problem The Peconic Estuary of eastern Long Island, New York, is undergoing development as the region transitions from a rural area dependent on agriculture and tourism to a suburban one with a larger year-round population. The glacial and coastal-plain sediments underlying Long Island comprise a sole-source aquifer system that supplies the region’s communities with potable water. The...
Science and Products
Groundwater Sustainability of the Long Island Aquifer System
The U.S. Geological Survey (USGS) has partnered with the New York State Department of Environmental Conservation (NYSDEC) to conduct a comprehensive study of the Long Island aquifer system. The major findings of this investigation include: The location of the boundary between fresh and salty groundwater is much closer to the shoreline than previously thought. The historical onshore saltwater...
Groundwater Flow Modeling - Long Island, New York
Numerical models provide a means to synthesize existing hydrogeologic information into an internally consistent mathematical representation of a real system or process, and thus are useful tools for testing and improving conceptual models or hypotheses of groundwater flow systems. The goal of this effort is to develop a regional model for the Long Island aquifer system to simulate changes in water...
The Use of Solute-transport Methods to Estimate Time-varying Nitrogen Loading Rates to the Peconic Estuary Resulting from Wastewater and Fertilizer Inputs to Groundwater in Suffolk County, New York (Peconic Solute Transport)
Problem The Peconic Estuary of eastern Long Island, New York, is undergoing development as the region transitions from a rural area dependent on agriculture and tourism to a suburban one with a larger year-round population. The glacial and coastal-plain sediments underlying Long Island comprise a sole-source aquifer system that supplies the region’s communities with potable water. The...