Cooling down without Air Conditioners

[ShadowHM]

I would question the effect on the lake's ecosystem if a large number of facilities began to alter the natural deep water temperature significantly.

I wondered about where the warmed up water goes myself. However, it is being fed into the city's water treatment system for general use by the city. Since the city would be drawing water from the lake in any case, it seemed like a minimal loss to the lake's ecosystem to have it drawn from the colder section rather than a shallower level.