As the extreme dry weather continues and the prospect of widespread drought looms, the water companies are the focus of a barrage of ongoing criticism – with leakage, executive pay and shareholder dividends topping the list of complaints.

Writing in The Telegraph newspaper, Environment Secretary George Eustice MP is calling for the introduction of more hosepipe bans as concerns over a period of extended drought grow.

Thames Water has come in for particular attention – last week in a highly critical article The Telegraph also revealed that the water company’s £250 million desalination plant at Beckton on the Thames Tideway which is meant to be used during drought periods, high demand periods or emergencies is currently out of action.

The article states:

“As hosepipe bans were imposed on a million more people across the south of England, Thames Water admitted that a major water desalination plant opened by the Duke of Edinburgh in 2010 will not work until next year at the earliest.

“The company had repeatedly assured regulators as recently as January that the plant in Beckton, east London, was ready to be switched on “for use in drought”, claiming it would help provide fresh drinking water to up to 400,000 households every day….

“On Wednesday a source at Ofwat, the water regulator, said it would look into Thames Water’s management of the plant during this year’s shortages. “

In a subsequent article entitled “Thames Water shut down emergency drought plant to save money’, the newspaper quotes Stephen Timms, MP for East Ham, as saying:

“It does seem puzzling to me when clearly we are in a situation which is exactly the kind of situation where this plant was intended to help us, it seems very strange that it’s out of action.

“If it’s planned maintenance, then surely you plan for a time other than when it’s most likely to be used?

“Is it because of the cost of electricity on it and they just aren’t willing to pay and run it? In which case obviously, they should tell us.”

The article also says that “current maintenance is focused on fixing pipework and electrical systems, the company said, as part of a planned £34 million project.”

Thames Water has been urging residents to control their water usage and limit consumption around the home - suggestions include taking shorter showers, limiting hosepipe use, fixing leaky loos and dripping taps, turning taps off when brushing teeth and waiting until there is a full load before running the dishwasher or washing machine.

Thames published its draft Drought Plan in June 2021 – following a period of consultation which concluded at the end of July 2021 the utility then submitted updates to the draft Drought Plan and technical appendices to Defra in early 2022. Thames’ own Statement of Response to the consultation responses said:

Draft Drought Plans says Thames has been undertaking maintenance to improve resilience of desal plant and ensure it can provide reliable water supply when needed

During periods of drought Thames Water’s water supply becomes increasingly dependent upon groundwater in the major aquifers of the Thames catchment.

The principal update to the plan was the reduction of the desalination scheme contribution at Beckton (TGWTW) by a third – down from 150 Ml/d to 100 Ml/d.

According to Thames, the output of the plant is lower than the licensed abstraction volume because there are “significant treatment losses incurred as a result of the desalination process.”

Folowing a review of the TGWWTW in 2017/18, the water company identified that the works needed “a substantial mid-life upgrade” and a programme of work was implemented, commencing in AMP7 to undertake “significant remedial upgrade works” to the plant so that its output could be maintained reliably at 100Ml/d.

The water company said that over the past 18 months it has been undertaking maintenance on the desalination plant to improve the resilience of the plant and ensure that the plant can provide a reliable water supply when it is needed.

The Plan states:

“On the basis of experience gained during the commissioning process, subsequently operating the site in 2012 and more recently, it is expected that the ‘ramping up’ time to implement the plant at full output will take between 4-6 weeks.

“This estimate is based on our current protocol of running the plant in the early part of the year to ensure it is in state of readiness so that the ramping up to close to maximum output is from a status of water into supply of approximately 50 Ml/d. Because of the proactive approach taken in the revised drought protocol this procedure can be commenced well in advance of the likely need to implement the scheme.”

“….We can confirm that Thames Gateway has the capability to achieve 100Ml/d. The plant is run annually for a period at lower volumes of at least 25Ml/d, as per the licence agreement, to maintain operating capability. The designed intermittent use of the plant means we need to replace perishable equipment once used, such as costly membranes. To manage these replacement costs, and also high operating costs, we will only utilise the full capacity of the plant when required.

“Since commissioning and testing and following further subsequent periods of use of the plant, we have had the opportunity to learn about the operation of the plant on an estuary with changing salinity.

“This has led to working improvements that have optimised the operational practice, and also awareness of the required maintenance to maintain the intermittently used equipment.”

“The plant was designed to achieve 150Ml/d against historic droughts, and not to deal with more extreme droughts that are expected to be of greater intensity and less water availability.

“….salinity levels in the upper and middle Thames Tideway are forecast to show greater variability, impacting the current running of the plant. To improve resilience to these conditions we are undertaking a works upgrade to improve the resilience of the plant so that it will be capable of 100Ml/d sustained output in future drought periods.”

The water company is now currently awaiting final approval of the Draft Plan by Defra which will direct Thames to publish the final version.