Rochester Water Hardness & Quality Report (2026)

Residents of Rochester receive their water from South East Water. The supply originates from the North Downs Chalk Aquifer, specifically drawn from boreholes drilled into the chalk bedrock beneath the Medway valley. This underground source is the sole origin for the public water supply in the area, with all water treated before distribution to homes and businesses.

The water's journey begins deep within the North Downs Chalk Aquifer, a significant geological formation primarily composed of chalk. This porous limestone bedrock, laid down millions of years ago, is rich in dissolved minerals, particularly calcium carbonate. As water percolates through the chalk, it picks up these minerals, leading to the characteristic hardness observed in the supply drawn from the Medway valley.

This water registers at 15.7°Clark on the German hardness scale, classifying it as hard. Homeowners may notice increased scale buildup on faucets, showerheads, and inside appliances like kettles and water heaters. Using less soap and detergent for washing and cleaning is often a practical adjustment. For those concerned about appliance longevity or experiencing significant scaling, installing a water softener is a common solution.