The flooding hit much of Severn Trent's operating area

Describing the events as "unprecedented in the recent history of the UK water industry", it added it expected to claim back �10m-�20m through insurance.

The flood crisis forced Severn Trent to temporarily shut its Mythe Water treatment works near Tewkesbury.

It added that it bought and distributed 50 million litres of bottled water.

The firm said it also deployed more than 2,000 of its own staff and contractors from other firms to deal directly with the impact of the floods.

While the �25m-�35m cost range is its initial estimate of the impact, it said the final figure would not be known until two inquires were completed.

Severn Trent is investigating both the general flooding and its own flood risk management.

The company added that it was making up to �3.5m available to support the affected communities recover from the incident.