Clarence-Rockland Water Hardness & Quality Report (2026)

Clarence-Rockland's drinking water is managed by the City of Clarence-Rockland, drawing from a local lake or surface water source in the eastern Ottawa Valley corridor — the community east of Ottawa in Prescott and Russell County serving as the largest bilingual (French–English) municipality in Eastern Ontario. Water undergoes coagulation, sedimentation, filtration, UV disinfection, and chloramination, meeting all Guidelines for Canadian Drinking Water Quality (GCDWQ) requirements. Hardness measures 175.5 mg/L (10.3 gpg) — classified as hard by Health Canada, notably harder than Ottawa's typical Ottawa River supply (116–120 mg/L) and reflecting the local supply's greater contact with eastern Ontario carbonate geology.

Clarence-Rockland's 175.5 mg/L is significantly harder than the Ottawa city supply (116–118 mg/L) that characterises the Ottawa River corridor. The eastern Prescott and Russell County area is underlain by Ordovician limestone and dolostone of the Ottawa Embayment — the same carbonate geology that produces moderately hard water throughout eastern Ontario. The local lake or surface water supply in the Rockland distribution zone, drawing from sources with greater contact with this soluble carbonate bedrock than the Ottawa River main channel, produces the harder 175.5 mg/L reading.

At 175.5 mg/L, Clarence-Rockland residents experience regular scale deposits — monthly kettle descaling is typical. Hot water tanks benefit from periodic flushing. The City of Clarence-Rockland provides water quality information in both official languages at clarence-rockland.com. Health Canada lead precautionary guidance applies to residents in the community's older Rockland village core and historic Clarence Village properties, where pre-1970 plumbing infrastructure may include lead or galvanised service connections.