Water companies across England and Wales will submit plans to Ofwat today (28 September) that detail how they intend to address the shortcomings identified in their handling of the “Beast from the East”.

Widespread disruption to the network in the aftermath of the freeze/thaw in March left more than 200,000 people without water for up to four days.

Ofwat’s review into the sector’s response during the period required four water companies – Thames Water, Severn Trent, Southern Water and South East Water – to submit a detailed externally audited action plan of how they will address the issues identified.

Overall, the “Out in the Cold” review, published on 19 June, painted a mixed picture of company performance. It found some companies responded well and protected customers but others fell short with their advance planning, response and communication with customers.

Ofwat will scrutinise the plans and will “step in” if it feels any company has not gone far enough.

Rachel Fletcher, chief executive of Ofwat, said: “The harsh weather in the spring left many customers out in the cold with no running water, in some cases for days. While a number of water companies and their hard-working staff stepped up and did well by customers, others fell well short, particularly when it came to providing bottled water, help for the most vulnerable, or clear, timely communication.

“We expect the companies that let their customers down to have learned the lessons of what went wrong during the freeze/thaw, and to show that they are now prepared to protect their customers, whatever the weather brings. This would be a great result for customers. If companies do not convince us of this, we won’t hesitate to step in.”

A spokesperson for Severn Trent said: “By putting in place the actions we’ve highlighted in our report we’re confident we’ll reduce the likelihood of future weather-related events becoming incidents, and be better prepared for, and equipped to deal with, those that do.

“We’ve already been encouraged by the positive impact of the actions we’ve already implemented, as seen by our response to the extremely hot summer this year.

“We now need to implement the remaining actions and ensure they become fully embedded within Severn Trent and our ways of working. In doing so, we’ll provide our customers and stakeholders with full confidence in our ability to respond to future challenging situations.”

The Consumer Council for Water (CCWater) published new guidance for the water sector yesterday about how companies can improve how they deliver priority support to consumers in vulnerable circumstances.

It referenced the severe cold weather in March this year, which put a “spotlight on the water sector”.

CCWater said consumers who found themselves in vulnerable circumstances were among the worst affected during the incident.  The vast majority (93 per cent) said they did not get any additional support from their company.

Tony Smith, chief executive of the Consumer Council for Water, said: “Water companies need to prove that they have listened to consumers and really learned lessons from the service failures we witnessed in March.

“Customers will want to know that these plans are tested and ready, and we’ll be expecting a tough response from Ofwat should any of the company plans fail, or further problems occur in future.”

Ofwat intends to publish a response to the reports by mid-November.