York University Heights Water Hardness & Quality Report (2026)

York University Heights (a north Toronto community near York University's Keele Street campus and Black Creek Drive, between Finch Avenue West and Steeles Avenue) receives its drinking water from the City of Toronto, drawing from Lake Ontario via the F.J. Horgan Water Treatment Plant on the eastern lakeshore. Water is treated using ozonation, biofiltration, UV disinfection, and chloramination, meeting all Guidelines for Canadian Drinking Water Quality (GCDWQ) standards. Hardness in this distribution zone is 232.5 mg/L (13.6 gpg) — classified as very hard by Health Canada, with TDS of 584 mg/L, consistent with the northwest Toronto distribution corridor.

York University Heights receives F.J. Horgan plant Lake Ontario supply through the northwest Toronto distribution network — the same very hard Lake Ontario source (dissolved Silurian and Devonian carbonate from the Great Lakes basin) as the adjacent Glenfield-Jane Heights (238 mg/L) and Downsview-Roding-CFB (238.5 mg/L) zones. The slightly lower 232.5 mg/L compared to these adjacent zones may reflect the sub-zone's specific distribution routing at the far north end of the Toronto network near the Steeles Avenue boundary with York Region.

At 232.5 mg/L, York University Heights residents face persistent hard water challenges — kettle and showerhead descaling every one to two weeks is typical. The community's high proportion of university students and post-secondary renters occupying older apartment buildings benefits from the City of Toronto's multilingual water quality guidance and lead service line information at toronto.ca/water. Annual hot water tank inspection and flushing are recommended for all residents in this characteristically very hard northwest Toronto supply zone.