Early warning system to forecast maximum temperature in drinking water distribution systems

Climate change poses new challenges in preventing the exceedance of the maximum allowed temperature in the drinking water distribution system (DWDS). The objective of this article is to evaluate the feasibility of forecasting the maximum temperature in the DWDS. Two options were analysed: (1) using the records of the last day as forecast for the coming 2 days and (2) using 2-day weather forecast data. The maximum water temperature in the DWDS was modelled for a Dutch city for a warm period during summer 2006. Actual meteorological records and historical weather forecasts were used. Results for the daily maximum temperature for June–July 2006 based on the high resolution limited area model predictions showed a 0.09 °C average mean error and a maximum error of 0.3 °C, while using the last day record as forecasted showed a mean error of 1.09 °C and a maximum error of 2.5 °C. These results indicate that it is possible to predict the daily maximum water temperature in the DWDS using the weather forecast information or using actual records as a short-term prediction. These types of simulations can serve as an ‘early warning system’ to monitor drinking water temperature for taking measurements to avoid exceeding the maximum allowed temperature.