Fighting heatwaves locally: the importance of dispersed water sources  

Heatwaves are one of the features related to climate change occurring in diverse areas of the planet, being associated with excess mortality. Strategies to mitigate its effects with low environmental impact, including low energy consumption, will be especially valuable. 
We discuss diverse issues related to the  role of dispersed water sources in fighting heatwaves by contributing to "urban oasis" (they also help to mitigate coldwaves). Harnessing these resources will promote the conservation of heritage engineering structures, using already available water occurrences, and could also be relevant for future civil engineering works. 
As discussed in our previous work, historic civil engineering structures could be seen as cultural markers of water occurrences, and one can find, e.g., in Braga (NW Portugal), historic fountains with significant discharge, even at times of drought. Frequently, inventories of these works are available, which need to be complemented with fieldwork, as minor local structures, as well as springs, will generally not be recorded.
Water sources for oasis effects could be incorporated in urban planning for structures to be developed, promoting new perspectives in architecture and civil engineering, as is illustrated by the waterfall in the rock wall at the side of the opera house in A Coruña (NW Spain). This could be useful also for activities like carwashing, which are a regular point of contention, and that will have, hence, their specific source of water. These projects can also include other cooling options, like cool materials or vegetation, for enhanced effect. 
In this way, science research could promote urban planning policies, which would  foster science research, in a synergistic approach, favouring the convergence of geology with history and archaeology for locating water sources, and of civil engineering, heritage studies, architecture and city planning in their use, having also potential for teaching and community strengthening.