Professor of Environmental Sciences
Hydrogeology and Groundwater Modelling
- Ph.D., 1982, Minnesota
- Ir., 1976, Delft University of Technology (Netherlands)
The research group focuses on the development and application of groundwater flow models, which use a rather new modeling technique: the analytic element method.
Conjunctive Surface/Groundwater Modeling. Regional groundwater movement is composed of infiltrating rainwater which eventually finds its way to surface waters. Traditionally, when modeling groundwater, surface water bodies (streams, lakes, etc.) are merely seen as "boundary conditions" on the groundwater elevation. It is now possible to predict the groundwater inflow rates into the streams, in order to compare it to observed "base flows" in the streams. By integrating this stream flow analysis in the models, Haitjema's group has developed a coupled surface water-groundwater model, where average base flow in streams is an additional calibration target.
Three-Dimensional Flow Modeling. Most saturated flow models, particularly when applied on a regional scale, deal with horizontal flow only. When modeling groundwater flow on a local scale, however, a complete three-dimensional solution may be needed. Haitjema is developing three dimensional solutions with several features. For example, he is including partially penetrating wells in a horizontal flow model. The resulting model is very efficient, modeling three-dimensional flow locally (near the well), while treating the regional flow as horizontal.
Nonpoint Source Pollution. Funded by the USDA, the analytic element model GFLOW was used to model the Walnut Creek watershed in Iowa. Special attention was given to capture the main hydrologic characteristics in an effort to simplify the model so that many watersheds can be represented in a single supra-regional (GIS) model. The research yielded useful insights in the distribution of groundwater residence times in watersheds, a crucial factor in describing the fate of nonpoint source pollution.
Fracture Flow Modeling. Horizontal groundwater movement in fractured rock has been modeled by use of the "distinct element method." A prototype code, FRACNET, was used to determine equivalent porous media conductivities for fracture networks, was succeeded by a more elaborate code, FRACFLOW, used to model dispersive contaminant transport at the Ammunition Burning Grounds of Crane Naval Weapons Support Center in southwest Indiana.
Kraemer, S.R., and, A modeling approach to regional fracture flow systems: (1989). International Conference, "Solving Groundwater Problems with Models," Indianapolis, Indiana, Feb. 7-9, 1989.
(1991). An analytic element model for transient axi-symmetric interface flow. Journal of Hydrology 129, p. 215-245.
(1992). Modeling regional groundwater flow in Fulton County, Indiana. Ground Water 30 (5), p. 660-666.
(in press). On the residence time distribution in idealized groundwatersheds. J. Hydrology.