A weather radar and processing system has been developed in conjunction with North West Water Ltd., a water utility responsible for the supply of potable water and the treatment of wastewater in the north-west of England. The primary objective has been to develop a radar system which can produce accurate and reliable quantitative estimates of rainfall at a temporal and spatial resolution commensurate with the requirements of urban drainage system modelling. This paper describes procedures for removing ground clutter and adjusting radar estimates of rainfall (using the Probability Matching Method). An archive of stratiform rainfall event data has supported an objective assessment of the radar data quality using a dense gauge network and simulated flow hydrographs for an urban drainage system. The results indicate that the adjusted radar data are of comparable accuracy to the dense raingauge data and are therefore of sufficient accuracy to be used for the management of water resources within an urban environment. The data processing and adjustment procedures have been incorporated into a real-time data processing and display software package (ARTIST) which is briefly described in the paper.