Finding (subsurface) anthropogenic heat sources that influence temperature in the drinking water distribution system

“The water temperature in the drinking water distribution system and at the customers’ taps approaches the surrounding soil temperature at ca. 1 meter depth. Water temperature is an important determinant of water quality, since it influences physical, chemical and biological processes, such as absorption of chemicals and chlorine decay. In the Netherlands drinking water is distributed without additional residual disinfectant and the temperature of drinking water at the customers’ tap is not allowed to exceed 25 ºC. Routine water quality samples at the tap in urban areas have shown locations with relatively high soil temperatures compared to the expected modelled soil temperatures, so called ‘underground hot- spots’. In the last decades, the urban sub-surface is getting more occupied with other sub-surface infrastructures and some of which can be heat sources. A few recent studies tackle the anthropogenic sources and their influence on the underground, but at coarse spatial scales. However, little is known about the urban shallow underground heat profile. Our research focuses on developing a method to identify and to localize potential underground hotspots at -1.0 m at a small spatial scale. First a literature study was done to identify possible sources of the underground hot-spots and secondly a method to search for the locations of these hot-spots was determined.”

(Citation: Agudelo-Vera, C.M., Blokker, E.J.M. – Finding (subsurface) anthropogenic heat sources that influence temperature in the drinking water distribution system – CCWI, Amsterdam, 7-9 november 2016)