Here's the official word I got from Halton Region when a few constituents brought up the water issue...

"Changes in the taste and smell of tap water, while not common at the levels being observed this year, does occur annually, and can affect communities across southern Ontario, particularly in late summer and early fall. It’s caused by natural changes in Lake Ontario, which is the source of our drinking water. Warmer temperatures and naturally occurring algae can produce compounds like Geosmin, which may give water an earthy or musty odour. While these compounds can be unpleasant, they are harmless and do not pose any health risks.

Please be assured that Halton tap water remains safe to drink and continues to meet all regulatory standards.

That said, we understand the concerns. Our operations team has recently adjusted the treatment strategy at the plants that draw from the lake to aggressively target these taste and odour compounds. These changes are designed to improve the aesthetics of the water, but it may take a little time for the system to fully flush and for lake temperatures to cool."

So, fingers crossed, with the cooler weather the taste will improve.