There is a link between water temperature and fine spray shower heads. Low water temps, i.e. energy saving, allow the bacteria to grow and fine spray, i.e water saving, shower heads aerosolize the bacteria allowing it to be inhaled. Once in the lungs it enters the blood stream.
Neat uh? Some cities and hotel chains recognize this and keep their water hot. To prevent scalding they install special valves.
It always seems to be in multi-unit facilities water tanks.
Another good reason not to live in rack and stack cells like our libtard masters want.