PhD defense: Britta Bockhorn

Britta Bockhorn defends her thesis: 

Landscape Technology: Improving the hydraulic performance of stormwater infiltration systems in clay tills

Assessment Committee

Lecturer Dr. Patricia Göbel, Institute of Geology and Palaeontology – Applied Geology, University of Münster, Germany

Research Professor Dr. Jens Christian Refsgaard, GEUS, Denmark

Professor Peter Knudegaard Engesgaard (chair), Department of Geosciences and Natural Resource Management, University of Copenhagen, Denmark


Professor Marina Bergen Jensen, Department of Geosciences and Natural Resource Management, University of Copenhagen, Denmark

Senior Researcher Knud Erik Strøyberg Klint, GEUS, Denmark


Low permeable clay tills, which cover many cities of the Northern Hemisphere, pose a challenge for stormwater infiltration practices. However, clay tills are amongst the most heterogeneous types of sediments, and hydraulic conductivities can vary by several orders of magnitude.

This PhD study was initiated with the objective to test and evaluate if the hydraulic performance of stormwater infiltration systems can be significantly improved, the site-specific geological heterogeneity being incorporated into the design and siting of such systems. The assessment is based on different hydrogeological and hydrogeophysical field investigations on two Danish clay till sites, and one modeling study with the integrated surface water and groundwater model HydroGeoSphere.

Results show that geological heterogeneity in clay tills can have a significant impact on the hydraulic performance of stormwater infiltration systems. Geoelectrical surveying, spear auger mapping and field infiltration tests can reveal the geological heterogeneity at different scales and represent three ideal mapping steps for the optimal sizing and siting of stormwater infiltration systems. The selection of the most appropriate mapping method should be done on a case-by-case basis for each investigated site and with consideration of the type of infiltration device to be implemented, as well as the density of belowground infrastructure.

After the PhD defense there will be a reception.