United Utilities said too much rain had affected its performance in the past twelve months and would knock £25 million from its incentive payments.
Rainfall was 50% higher across its North West region than a year ago and a third higher than the long-term average, said the utility, with fourteen named storms and nine since September.
As a result, United’s 2023/24 outcome delivery Incentive (ODI) would be around £40m net or some £25m lower than expected.
Outcome delivery incentives are awarded to utilities for meeting operational targets.
In a trading update, United Utilities highlighted sustainability awards it had received even though, along with its peers, it has been blasted by the Environment Agency and regulator Ofwat for repeated sewage dumping and pipe leaks.
Last year, a new set of rules to stop pollution by the utilities was introduced and United said it had been “recognised as part of the Taskforce on Nature-related Financial Disclosures (TNFD) early adopters”.
On financial numbers, United said it had "continued to deliver strong operating performance since our interim results, resulting in no material changes to 2023/24 financial guidance".
Shares rose 0.6% to 1,032p.