John Reynolds of Castle Water reviews impending tariff increases from 1 April, and looks at changes from 2027-30

March 23, 2026

Tariffs from the outside water tariff rises every April are still a postcode lottery. For the largest wholesale areas affecting Castle’s customers April price rises vary from +34% for large customers in the Southern Water area (for clean water services), to reductions of 5-6% in sewerage charges for Thames and

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