2011 Darcy Lecturer
Stephen E. Silliman, Ph.D.
The 2011 Henry Darcy Distinguished Lecturer Stephen “Steve” E. Silliman, Ph.D., joined the University of Notre Dame in January 1986 and is currently a professor of civil engineering and
geological sciences, with an emphasis in groundwater hydrology. He received his bachelor’s degree in civil engineering from Princeton University, and both a master’s degree and Ph.D. from the Department of Hydrology and Water Resources at the University of Arizona. At Notre Dame, he has been responsible for developing a research program in theoretical and applied aspects of groundwater hydrology. He has also enjoyed teaching a diverse set of courses at the undergraduate and graduate levels, has served as associate dean for undergraduate programs in the College of Engineering, and currently serves as associate chair in his home department. He is also the principal investigator of the Notre Dame Benin Research Program.
Silliman’s research focus is divided between his theoretical/laboratory studies on groundwater flow/transport processes and water resource development/management in developing countries. His work on groundwater flow/transport has historically been focused on studies of the impact of heterogeneity in the saturated zone (flow, chemical transport, particle transport). Recently, this work has become more focused on the vadose zone as well as wellhead management strategies under uncertainty.
His work in developing countries was initially took place in Haiti, but has been focused in Benin in West Africa for more than a decade now. In these efforts, he has worked with his students (undergraduate and graduate) and Benin colleagues on such efforts as training local populations to monitor water quality, and modeling and field characterization of coastal hydraulics with a focus on the potential for saltwater intrusion of the wellfield serving Cotonou, the largest city in Benin, and assisting in the drilling/equipping of a number of manual-pump groundwater wells.
His research has been supported by a number of agencies, ranging from the Department of Energy and the National Science Foundation to private foundations.
Silliman is a member of NGWA. He has served as an associate editor of NGWA’s Ground Water®, as well as several other journals. He is also active in the American Geophysical Union.
Darcy Lecture Series host institutions can select one of two lectures.
Development of Reliable Hydrologic Data Sets in Difficult Environments: Case Studies from Benin, West Africa
Reliable hydrologic data are critical for sound hydrogeologic analyses and for the subsequent policy decisions based on those analyses. However, obtaining such data sets in the face of limited budgets and limited access to field sites can be a daunting challenge, particularly in rural regions in developing countries. Experience in Benin demonstrates that such challenges are best met through close collaboration with a number of in-country entities (universities, local populations, government agencies, and NGOs) and integration of hydrologic expertise with political, social, and cultural considerations.
This presentation focuses on a series of case studies from Benin directed at developing data sets involving: (1) regional water quality, (2) temporal variation in nitrate contamination in rural groundwater wells, and (3) temporal variation in hydraulics and water quality related to saltwater intrusion as well as anthropogenic contamination in coastal areas. This presentation demonstrates both the value of statistical analysis in the design and implementation of sampling plans in these difficult environments, as well as the power of close collaboration with in-country colleagues and local populations.
Characterization of a Complex, Sole-Source Aquifer System in Benin, West Africa
The Godomey wellfield is the sole source of freshwater for Cotonou, Benin. The Cotonou/Calavi area is the largest population center in Benin, with an estimated population of between 1.5 and 2 million people. Located directly on the Atlantic coast, this population center is also bordered by the southern and western shores of a large, shallow lake. Groundwater wells serving this population are located about 6 km north of the Atlantic coast and as close as 1 km to the western shore of the lake. With most production wells located within partially confined portions of this complex aquifer system, this water resource is threatened by contamination from saltwater intrusion (both from the lake and the ocean) and anthropogenic activities.
Collaboration among scientists and students from the United States and Benin has allowed development of increasing insight into the hydrogeology of this important coastal aquifer system. Research efforts discussed in this presentation include numerical modeling, hydraulic testing, water quality characterization, and electrical resistivity surveys. Discussion of a number of technical and social/cultural issues encountered during this research effort illustrates the value of close cooperation with in-country collaborators, including those from both the technical and social science disciplines.
Submit your request to have the 2011 Darcy Lecture presented at your event. Requests must be received by October 15, 2010.