Artificial lakes to moderate microclimates?

Hi everyone, this has been driving me nuts for a few hours.

During my WSET Diploma I recall someone mentioning a producer in Bordeaux who constructed an artificial lake/reservoir in order to moderate the microclimate of their vineyards. Numerous online searches have yielded nothing. I asked one of my classmates who reckons it might be Chateau de Reignac, but I could find no sources to back this up.

Does anyone here know who the producer might be, or do you have any other examples around the world where an artificial body of water was constructed for viticultural reasons?