ISLE of Wight customers of Southern Water will receive a rebate — circa £60 each — following the final Ofwat penalty notice.

It follows the notice issued by the water regulator in June 2019, in which the key finding was that some of Southern Water's wastewater treatment sites were manipulated by staff to pass sampling tests they otherwise might have failed.

The final notice includes plans for payments to former customers and a commitment to improved transparency on environmental performance.

It confirms payments to former customers and the reduction in wastewater charges for current customers will total £123 million, together with a £3 million fine.

As well as reducing charges for wastewater customers from 2020 to 2025 as previously announced, following a public consultation, three further commitments have been agreed by Southern Water. The plans now include making payments to wastewater customers of Southern Water between 2015 and 2020 but who are no longer living in the region.

This will start in April 2020 and advice on how to claim will be published nearer the time.

The notice also reveals plans for greater transparency on environmental performance which will see information available on pollution incidents, flow and spill reporting, wastewater treatment works compliance, regional bathing water compliance results, emissions and river levels published on the company website (subject to any constraints on reporting environmental information or data provided by the Environment Agency).

The third commitment is to ensure employees do not receive bonuses and incentive payments for personal objectives linked to wastewater compliance when Southern Water fails to meet its relevant performance commitments.

Southern Water chief executive Ian McAulay said: "I'm pleased we have an opportunity to not only make appropriate amends to our customers past and present for the unacceptable failings of the past but to also commit to increased transparency on environmental performance.

"Since 2017 we have invested more than £100 million in improving our networks, systems and training our people.

"We are recognised as having made significant strides in improving our business. There is a lot more work to do but we are working hard to fully make amends to our customers and regain their trust."

A spokesperson confirmed: “Household bill payers that continue to pay wastewater charges after 1 April 2020 will receive a rebate linked to their usage levels by way of a reduction to their bills, on average, of approximately £14 in the first year.

"After this, the bill reduction could be, on average, approximately £9 a year until 2025 (the actual amounts will depend upon your wastewater charges and how many former customers apply for payments under the new scheme). The reduction will also be subject to inflation.

"Former customers – households that paid wastewater charges between 1 April 2015 and 31 March 2020, but who no longer pay from 1 April 2020 – are eligible for a payment at the rate of approximately £9 for each of the five years (or part of a year) that they paid wastewater charges.”

There is an FAQ for customers at