Abstract
On 26 August 2010 the eastern part of The Netherlands and the bordering part of Germany were
struck by a series of rainfall events. Over an area of 740 km2 more than 120 mm of rainfall were
observed in 24 h. This extreme event resulted in local flooding of city centres, highways and
agricultural fields, and considerable financial loss.
We investigated the unprecedented flash flood triggered by this exceptionally heavy rainfall event in
the 6.5 km2 Hupsel Brook catchment, which has been the experimental watershed employed by
Wageningen University since the 1960s. This study aims to improve our understanding of the
dynamics of such lowland flash floods. We present a detailed hydrometeorological analysis of this
extreme event, focusing on its synoptic meteorological characteristics, its space-time rainfall dynamics
as observed with rain gauges, weather radar and a microwave link, as well as the measured soil
moisture, groundwater and discharge response of the catchment.
We found that the response of the Hupsel Brook catchment can be divided into four phases: (1) soil
moisture reservoir filling, (2) groundwater response, (3) surface depression filling and surface runoff
and (4) backwater feedback. During this extreme event some thresholds became apparent that do not
play a role during average conditions and are not incorporated in rainfall-runoff models.
Because of the large spatial extent of the rainfall event, many brooks and rivers in the Netherlands
and Germany flooded. With data from several catchments we investigated the influence of rainfall and
catchment characteristics (such as slope, size and land use) on the reaction of discharge to rainfall.
Original language | English |
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Publication status | Published - 2011 |
Event | EGU Leonardo Conference Series on the Hydrological Cycle, Bratislava, Slovakia - Duration: 23 Nov 2011 → 25 Nov 2011 |
Conference
Conference | EGU Leonardo Conference Series on the Hydrological Cycle, Bratislava, Slovakia |
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Period | 23/11/11 → 25/11/11 |