Use of weather radar by the water industry in Scotland

Rainfall data are a key source of information used by the UK water industry to perform its diverse regulatory functions. Raingauges have traditionally been used, but radar rainfall data are increasingly being utilised. Within Scotland, the public body Scottish Water has the responsibility for supplying drinking water and the collection and treatment of wastewater. An outline of Scottish Water’s requirements and use of weather radar data is presented along with a brief description of the Hyrad Weather Radar System. A case study illustrates a novel method for post-event analyses of storm events associated with surface water flooding incidents. These analyses combine the analytical capabilities of Hyrad with the Flood Estimation Handbook depth-duration-frequency rainfall model to obtain estimates of rainfall return periods. The estimates are used to assess whether urban drainage systems performed within design specifications or if remedial action is required to comply with the regulatory framework. Finally a look forward is given of future planned applications of weather radar within the water industry in Scotland.