We've been seeing water temperatures around 10°C (50°C). This is rather cool, and at one point, Operations was looking at blending in some warmer water from other sources (wells, for example), to raise the temperature. (Why? The "contact time" calculations are sensitive to temperature. Chemical reactions proceed faster at higher temperatures, so at low temperatures, water has to spend more time in contact with chlorine to get the same guaranteed inactivation rate for bacteria.)
Today, I'm looking at data from the past weekend, and I'm seeing temperatures as low as 6.3°C (43.3°F).
My tankless water heater increases the temperature of water flowing through it by 45°F, so with water of this temperature coming in, it tops out at 88.3°F.
If global warming continues, I may have to install some sort of temperature booster.
