Christian Langevin
Biography
Dr. Christian Langevin is a research hydrologist with the U.S. Geological Survey Earth Systems Modeling Branch. He presently sits in the Mounds View Office in Minnesota, which is part of the Upper Midwest Water Science Center. Dr. Langevin is the primary USGS contact for the MODFLOW program, which is used worldwide to simulate groundwater flow. His present research focuses on development and support of the MODFLOW 6 program and other related programs, such as FloPy, SEAWAT, MT3D-USGS, MODFLOW-USG, and MODFLOW-2005. Dr. Langevin began his career with the USGS in 1998 after completing his M.S. and Ph.D. at the University of South Florida in Tampa and his B.S. at the University of Wisconsin at Madison.
Science and Products
Seawater circulation in sediments driven by interactions between seabed topography and fluid density
Measurements of submarine groundwater discharge (SGD) in coastal areas often show that the saltwater discharge component is substantially greater than the freshwater discharge. Several mechanisms have been proposed to explain these high saltwater discharge values, including saltwater circulation driven by wave and tidal pumping, wave and tidal...
Konikow, Leonard F.; Akhavan, M.; Langevin, C.D.; Michael, H.A.; Sawyer, A.H.
MODFLOW–USG version 1: An unstructured grid version of MODFLOW for simulating groundwater flow and tightly coupled processes using a control volume finite-difference formulation
A new version of MODFLOW, called MODFLOW–USG (for UnStructured Grid), was developed to support a wide variety of structured and unstructured grid types, including nested grids and grids based on prismatic triangles, rectangles, hexagons, and other cell shapes. Flexibility in grid design can be used to focus resolution along rivers and around wells...
Panday, Sorab; Langevin, Christian D.; Niswonger, Richard G.; Ibaraki, Motomu; Hughes, Joseph D.
Estimation of capture zones and drawdown at the Northwest and West Well Fields, Miami-Dade County, Florida, using an unconstrained Monte Carlo analysis: recent (2004) and proposed conditions
Travel-time capture zones and drawdown for two production well fields, used for drinking-water supply in Miami-Dade County, southeastern Florida, were delineated by the U.S Geological Survey using an unconstrained Monte Carlo analysis. The well fields, designed to supply a combined total of approximately 250 million gallons of water per day, pump...
Brakefield, Linzy K.; Hughes, Joseph D.; Langevin, Christian D.; Chartier, Kevin Modeling variably saturated subsurface solute transport with MODFLOW-UZF and MT3DMS
The MT3DMS groundwater solute transport model was modified to simulate solute transport in the unsaturated zone by incorporating the unsaturated-zone flow (UZF1) package developed for MODFLOW. The modified MT3DMS code uses a volume-averaged approach in which Lagrangian-based UZF1 fluid fluxes and storage changes are mapped onto a fixed grid....
Morway, Eric D.; Niswonger, Richard G.; Langevin, Christian D.; Bailey, Ryan T.; Healy, Richard W.
Documentation of the Surface-Water Routing (SWR1) Process for modeling surface-water flow with the U.S. Geological Survey Modular Ground-Water Model (MODFLOW-2005)
A flexible Surface-Water Routing (SWR1) Process that solves the continuity equation for one-dimensional and two-dimensional surface-water flow routing has been developed for the U.S. Geological Survey three-dimensional groundwater model, MODFLOW-2005. Simple level- and tilted-pool reservoir routing and a diffusive-wave approximation of the Saint-...
Hughes, Joseph D.; Langevin, Christian D.; Chartier, Kevin L.; White, Jeremy T.
Simulated flow of groundwater and brine from a flooded salt mine in Livingston County, New York, and effects of remedial pumping on an overlying aquifer
Two ceiling collapses in the Retsof salt mine near Geneseo in upstate New York in spring 1994 resulted in the upward propagation of two columns of rubble through 600 feet of overlying shale and carbonate bedrock. This upward propagation formed a hydraulic connection between the lower confined aquifer (LCA) and the mine and allowed water from the...
Yager, Richard M.; Miller, Todd S.; Kappel, William M.; Misut, Paul E.; Langevin, Christian D.; Parkhurst, David L.; deVries, M. Peter Future of groundwater modeling
With an increasing need to better manage water resources, the future of groundwater modeling is bright and exciting. However, while the past can be described and the present is known, the future of groundwater modeling, just like a groundwater model result, is highly uncertain and any prediction is probably not going to be entirely representative...
Langevin, Christian D.; Panday, Sorab Improving sub-grid scale accuracy of boundary features in regional finite-difference models
As an alternative to grid refinement, the concept of a ghost node, which was developed for nested grid applications, has been extended towards improving sub-grid scale accuracy of flow to conduits, wells, rivers or other boundary features that interact with a finite-difference groundwater flow model. The formulation is presented for correcting the...
Panday, Sorab; Langevin, Christian D. Use of upscaled elevation and surface roughness data in two-dimensional surface water models
In this paper, we present an approach that uses a combination of cell-block- and cell-face-averaging of high-resolution cell elevation and roughness data to upscale hydraulic parameters and accurately simulate surface water flow in relatively low-resolution numerical models. The method developed allows channelized features that preferentially...
Hughes, J.D.; Decker, J.D.; Langevin, C.D. Effect of the difference between water-table elevation and hydraulic head on simulation of unconfined aquifers using MODFLOW
Provost, Alden M.; Langevin, Christian D. Predictive uncertainty analysis of a saltwater intrusion model using null-space Monte Carlo
Because of the extensive computational burden and perhaps a lack of awareness of existing methods, rigorous uncertainty analyses are rarely conducted for variable-density flow and transport models. For this reason, a recently developed null-space Monte Carlo (NSMC) method for quantifying prediction uncertainty was tested for a synthetic saltwater...
Herckenrath, Daan; Langevin, Christian D.; Doherty, John Effect of tidal fluctuations on transient dispersion of simulated contaminant concentrations in coastal aquifers
Variable-density groundwater models require extensive computational resources, particularly for simulations representing short-term hydrologic variability such as tidal fluctuations. Saltwater-intrusion models usually neglect tidal fluctuations and this may introduce errors in simulated concentrations. The effects of tides on simulated...
La Licata, Ivana; Langevin, Christian D.; Dausman, Alyssa M.; Alberti, Luca