Milliken Water Hardness & Quality Report (2026)

Milliken (a residential neighbourhood in far-north Scarborough, Toronto, near Sheppard Avenue East and McCowan Road — adjacent to the Markham boundary and predominantly a Chinese-Canadian community centred on Milliken Park and the Pacific Mall complex) receives its drinking water from the City of Toronto, drawing from Lake Ontario via the R.C. Harris Water Treatment Plant. 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 184 mg/L (10.7 gpg) — classified as very hard by Health Canada, intermediate between central Toronto's typical 230–240 mg/L and the lower-hardness eastern Scarborough sub-zones (Agincourt North 154.5 mg/L).

Milliken's 184 mg/L represents an intermediate zone in the northeastern Scarborough distribution area — harder than Agincourt North (154.5 mg/L) to the southwest but softer than the central Toronto baseline. Milliken's position at the far northern end of the Scarborough distribution network, adjacent to Markham, places it at a distribution routing junction that may blend or transition between the lower-hardness eastern Scarborough supply and the standard Toronto supply, producing the intermediate 184 mg/L characteristic of this northernmost Toronto neighbourhood.

At 184 mg/L, Milliken residents experience regular scale deposits in kettles and on showerheads — monthly descaling is typical. Hot water tanks accumulate scale and benefit from annual inspection and flushing. The City of Toronto provides water quality information at toronto.ca/water in multiple languages; multilingual water quality guidance is particularly relevant for Milliken's predominantly Mandarin- and Cantonese-speaking community, one of Toronto's largest Chinese-Canadian residential areas.