Hydrological and planting design of an experimental raingarden at the Royal Botanic Garden Edinburgh
A new experimental raingarden has been created at the Royal Botanic Garden Edinburgh (RBGE) to help cope with the impacts of more frequent and intense rainfall events. Raingardens offer a sustainable, nature-based solution to flood mitigation by mimicking natural rainwater retention and infiltration characteristics within a constructed bioretention system. By incorporating specially selected plants that can withstand both very wet and very dry conditions, raingardens also provide enhanced biodiversity capacity.This paper reports on the hydrological design of the raingarden, which is aimed at reducing the occurrence of waterlogging and localised flooding within RBGE, before discussing the selection and cultivation of the planting. It is hoped that the mix of plants chosen will encourage a great diversity of wildlife, providing nectar sources for insects and bees in summer, and homes for invertebrates and food for seed-eating birds in winter. With the raingarden having been in place for over a year at the time of writing, reflections on its maintenance and upkeep during that time and performance assessment for significant storm events will also be discussed.
BRAY, B., GEDGE, D., GRANT, G. & LEUTHVILAY, L. (2012). Rain Garden Guide. RESET Development, London.
CENTRE FOR ECOLOGY AND HYDROLOGY (2013). Flood Estimation Handbook, Centre for Ecology and Hydrology, Wallingford.
FLYNN, K.M. & TRAVER, R.G. (2013). Green infrastructure life cycle assessment: a bio-infiltration case study. Ecological Engineering, 55: 9–22.
FOULKES, J. (2017). The value of community engagement in botanic gardens with examples from the Royal Botanic Garden Edinburgh. Sibbaldia: The Journal of Botanic Garden Horticulture, 15: 121–128.
KELLY, D.A., KNOTT, D., WILSON, K. & KALAICHELVAN, A. (2019). The hydrology and biodiversity characteristics of an experimental raingarden at RBGE in Scotland. CIB W062, 45th International Symposium on Water Supply & Drainage for Buildings, Melbourne, Australia, 7–10 September 2019.
MARTIN, S. (2014). Climate ready? Exploring the impact and lessons from recent extreme events at Royal Botanic Garden Edinburgh for climate change adaptation in the horticulture sector. Sibbaldia: The Journal of Botanic Garden Horticulture, 12: 155–170.
MEHRING, A.S. & LEVIN, L.A. (2015). Potential roles of soil fauna in improving the efficiency of rain gardens used as natural stormwater treatment systems. Journal of Applied Ecology, 52(6): 1445–1454.
MURPHY, J.M., HARRIS, G.R., SEXTON, D.M.H., KENDON, E.J., BETT, P.E., CLARK, R.T., EAGLE, K.E., FOSSER, G., FUNG, F., LOWE, J.A., MCDONALD, R.E., MCINNES, R.N., MCSWEENEY, C.F., MITCHELL, J.F.B., ROSTRON, J.W., THORNTON, H.E., TUCKER, S. & YAMAZAKI, K. (2018). UKCP18 LAND Projections: Science Report. Met Office Hadley Centre, Exeter.
NATURAL RESOURCES CONSERVATION SERVICE (1986). Urban hydrology for small watersheds. Technical Release 55. United States Department of Agriculture, Natural Resources Conservation Service.
NOVÁK, V. (2012). Evapotranspiration in the Soil-Plant-Atmosphere System: Progress in Soil Science. Springer, Dordrecht.
RBGE (2019). Our history. Available online: https://www.rbge.org.uk/about-us/our-history/ (accessed May 2020).
WOODS-BALLARD, B., WILLSON, S., UDALE-CLARKE, H., ILLMAN, S., SCOTT, T., ASHLEY, R. & KELLAGHER, R. (2015).The SuDS Manual (C753).CIRIA, London.
ZHANG, S. & GUO, Y. (2013). Explicit equation for estimating storm-water capture efficiency of rain gardens. Journal of Hydrologic Engineering, 18(12): 1739-1748.
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