In Basel (CH), the thermal impact of various subsurface structures on urban groundwater resources, including five underground parking lots and a freeway tunnel, were investigated by monitoring systems. Data were analyzed together with meteorological and groundwater temperature data and results from heat-transport modelling.Significantly elevated temperatures between 18.8 and 21.1 °C were recorded in the underground parking lots, even in winter. Thus, underground parking lots emit heat into the surroundings all year. In comparison, data recorded in the freeway tunnel indicate that in the winter months heat can also be absorbed from below ground.In addition, the temperatures of underground parking lots show a clear dependence on the type of use: with a higher number of daily entrances and exits, greater daily temperature increases were detected, with differences of up to 2 °C. This became particularly clear in the "lockdown" period during the COVID-19 pandemic between March and May 2020.

Increasing drought induces growing water demands from crop farming. Subsequently, "traditional balances" among groundwater stakeholders shift, and opposition to administrative regulations becomes more likely. For counteracting resource-consuming intersectoral friction, two projects ("Water Networks") focusing on improving governance approaches were realized in selected districts. Round tables of selected representatives of regional groundwater stakeholders (drinking water, environmental protection, waterbody maintenance, forestry, agricultural irrigation) were established to enhance competences and understanding and to build mutual confidence. During all-day meetings with breaks for informal exchange, experts presented regional information including determinants for agricultural water demand. In particular, objective information was found lacking on recent and future irrigation demands for crops. Thus, potential regional irrigation needs were determined based on high-resolution soil data, climate data and distribution of primary crops. Clear trends towards increasing requirements of irrigation of up to 31% in regional average were identified until the end of the century. The need for continuing the platform discussions was a main conclusion of the participants.