Extracting heat energy from wastewater can be one component of a community’s overall strategy towards reducing both primary energy use and CO2 emissions. Investors and contractors must make individual decisions, based on the specific situation at a given site. However, a preliminary process of strategic location identification and selection can be helpful in coordinating such investments and construction projects. The approach outlined here is intended as an aid to decision-making, and the identification of sites, which can, from a technical point of view, be easily developed. It also aims to be an introduction to the subject for decision makers at a community and corporate level (e.g. city planners and network operators), and to offer a first, but by no means complete, overview. Taking the city of Oldenburg, Germany as an example, a model to aid decision-making was developed and tested. This was done within the scope of the German-Dutch Interreg Project ‘denewa’.