The development of a methodological approach for the use of UK climate change data for the design of rainwater drainage systems for buildings

There are a number of ways in which rainwater drainagesystems for buildings are sized. Fundamentally, however,all rely upon the specification and application of a rainfallintensity figure that reflects the geographical region inwhich the building is located and the anticipated durationof any given rainfall event. Most design methods interpreta rainfall event by equating this to a peak rainfall intensityfigure that is applied as a steady-state value. Little, if any,account is taken of climate change when specifying thisfigure. However, with the availability of state-of-the-artUK climate change projections data (UKCP09), it shouldbe possible to integrate change factors within the designprocess and to develop systems that better accommodatechanging precipitation patterns.Give that there are several ways in which UKCP09 datamay be used to identify the potential impacts of climatechange, and that guidance from advisory bodies is that themethod of data extraction and use should be matched tothe way in which the information will be applied, this paperpresents a proposed methodology for data users for whomthere is a need to better understand the possible changesin precipitation linked to future greenhouse gas emissionsscenarios.