Author(s)

J. A. Bals & M. A. Rijsberman

Abstract

Due to urbanisation and climate change, peak discharges have increased both in size and in frequency. Over the last few years heavy rainfall has shown the necessity of action, with water nuisance and flooding e.g. in the low lying polder areas in the Netherlands, Rhine, Elbe and Danube river basins. To mitigate the effects of urbanisation and climate change, local retention of water is an obvious measure to combat high peak discharges. Retention at the local level is the most effective. While in urbanised areas space typically is scarce and expensive, space designated for retention like ponds are of little economic value. In Western Europe, most research in the field of rainfall run-off and retention focuses on housing areas. In contrast, this study evaluates different possibilities for water storage at large buildings like factories, office buildings and greenhouses. Roof sizes up to several hectares lead to different technical solutions compared to solutions suited for housing areas, where individual roof sizes are much smaller. Different technological solutions for water storage have different hydrological characteristics. Systematically, water storage possibilities at different places relative to the building (e.g. in, on top of, under and next to) are evaluated as alternatives to surface water storage. Subsequently, the most promising possibilities are compared on technical, cost and legal aspects. Hydrological performance is simulated using a mathematical model. This paper investigates differences, identifies (dis)advantages and proposes solutions for implementation, taking these disadvantages into account. As an example, a case study of a new greenhouse area (about 400 ha) in the west of the Netherlands is used. Keywords: hydrology, water retention, peak rainfall, surface water, robust, benchmark, greenhouse area, synthetic bag.

Keywords

hydrology, water retention, peak rainfall, surface water, robust, benchmark, greenhouse area, synthetic bag.