To ask the Secretary of State for Health and Social Care, with reference to para. 2.1(d) of the Williamsgate treatment works fluoridation variation agreement, how many households were supplied with water from (a) Williamsgate and (b) Quarry Hill works on 31 October 2022.

By 31 October 2022, United Utilities had begun to transition the area supplied by Quarry Hill water treatment works onto the new supply from Williamsgate water treatment works.

The area served by the outlet main leaving Williamsgate water treatment works is the same as the area that was supplied by Quarry Hill water treatment works. The estimated number of properties covered by this area is 8,354. The number of properties that were supplied by Quarry Hill water treatment works before the transition was an estimated 8,354 properties.