Brighton Water Hardness & Quality Report (2026)

Southern Water supplies Brighton with mains water, drawing from multiple sources. The primary source is the Chalk aquifer beneath the South Downs, supplemented by surface water. This groundwater system is distributed through treatment plants serving the coastal area. The Chalk aquifer, a Cretaceous-age formation, is composed of pure calcium carbonate rock. As rainwater percolates through this permeable geology, it dissolves substantial quantities of calcium and magnesium minerals.

This hydrogeology is characteristic of South East England's chalk-based systems. The permeable chalk layers of the South Downs allow rainwater to dissolve significant mineral content as it passes through. This process results in a very hard water supply, typical for regions with this geological makeup. The Cretaceous formation's composition directly contributes to the high mineral levels found in the water.

Very hard water means Brighton residents often see significant limescale buildup on kettles, shower heads, and heating elements. Appliances like boilers and water heaters are particularly affected; scale accumulation reduces efficiency and increases energy costs. Washing machines and dishwashers may show reduced performance, leading to stiff laundry and diminished soap effectiveness. Installing a water softener is strongly recommended to protect plumbing and appliances from long-term damage. Residents can clean appliances regularly and maintain water heater temperatures below 60°C to minimize scale formation.