Threat of drought looms large

Lower-than-average rainfall in recent months has forced Southern Water to apply for a drought permit to refill one of its reservoirs. If rainfall doesn’t increase in the South East of England this winter, water companies will face drought in the summer. Katey Pigden looks at how companies are guarding against water supplies running dry.

The British weather is famously unpredictable. However, in recent years the country has faced increasingly extreme weather conditions with floods and droughts becoming more commonplace – and yes, both can be happening at the same time in different parts of the country, no wonder British people find weather such a fascinating topic of conversation.

That national pastime will generally greet rain with gloomy tutting. However, water companies who rely on winter rainfall to replenish vital resources, are currently eager for some sustained wet weather.

Without above average levels of rainfall this winter, some areas of the South East of England could face a drought during the summer months. There are a number of areas in the South East of England that experienced a particularly dry winter last year, followed by another dry start to this winter. As a result, reservoir and groundwater levels have remained low in parts of the region. Representative group Water UK says water companies in some areas are now “taking action” to help reduce the possibility of restrictions in the spring.

“Naturally, the water resources picture across the South East is varied as it reflects differing geographical areas and sources of water, but all companies will continue to work closely with the Environment Agency and the Met Office to monitor the situation over the coming months,” a Water UK spokesperson told Utility Week.

Complex environment

Water levels at Bewl Water reservoir fell below 33 per cent of its maximum 31,000-million-litre capacity, causing Southern Water to act. As a “precautionary” measure, the company applied to the Environment Agency on 5 January for a drought permit to pump water into the Bewl – the largest stretch of open water in the region. It is the first time Southern has had to apply for a drought permit since 2012.

On 17 January – the day Southern’s application was approved – the reservoir reached 52.5 per cent full. The water company says it aims to increase Bewl’s water level to 75 per cent by 1 April.

Speaking to Utility Week while the company was still waiting for a decision on its application, Ian McAulay, chief executive of Southern Water, said: “It’s a complex environment. You can get drought and you can get flooding at exactly the same time. These events are becoming more common. The really good thing for me is people are getting together and making sure we get the right message out there. We are taking things forward and putting them much more under the banner of resilience. Because it is absolutely resilience.”

McAulay describes Southern’s move as “the right thing to do”. “It’s precautionary. It’s about trying to take every step we can, working together to safeguard supplies to customers in the summer but also to make sure we manage the environment.”

But, he stresses the company “won’t just be looking at this as a short-term solution to the problem”. “We’ll be looking at what we can learn from it and considering how it will inform our planning for future years. We will also be exploring if there are things we can do in terms of strengthening our networks.”

“Rather than dealing with drought, we are dealing with resilience and, of which, drought and flooding are two subsets. With these events, rather than look at them in isolation we should be looking at them as part of the equation. I’m pleased with the concerted effort and collaboration, which has come about because of this.”

Greater flexibility

Southern Water says the permit will give the company “greater flexibility” to take water from the River Medway and River Teise and pump it into the reservoir to help boost its water level ahead of spring and summer.

The Environment Agency says in determining the application, it had considered the very low rainfall, the impact this has had on water supplies, as well as the responses to the public consultation. Area director Julie Foley says: “The Environment Agency has to balance the water needs of people, businesses and wildlife so we have carefully considered Southern Water’s application. We have decided to grant this temporary change to the existing licence, helping the company to refill the reservoir at a time of year when there will be less impact on the environment. We will carefully monitor any effects and take action if needed to ensure the environment is protected.”

Ofwat says that, during times of drought, it expects each water company to follow their operational drought plan and ensure that customers receive the levels of service they expect.

Each water company has a “duty to manage its water resources resiliently”, senior director John Russell tells Utility Week. “This means thinking long-term about challenges such as a growing population and climate change, cutting down on leakage and promoting good practices around sustainable water usage.”

Other affected companies

Although Southern Water is the only company to apply for a drought permit so far this year, it is not the only one in need of above average levels of rainfall in the coming months. SES Water and Affinity Water are also hoping for a wet winter.

Following a dry winter in 2016-17, Affinity Water says its groundwater resources remained below average for the whole of last year. Over the last three months, below average rainfall has meant that groundwater supplies, which are used to supply water, are now low.

Even with the wet December, the company says recharge of the aquifers was, in some areas, only 24 per cent of the long-term average. It says rainfall will need to be “significantly above average” in January, February and March to reduce the likelihood of water restrictions later this year.

Mike Pocock, director of asset strategy at Affinity Water, says: “We are constantly managing the water we have, through investing in new resources, installing new pipelines to move water around our network, and finding and fixing leaks as quickly as possible.

“With our water resources at low levels, we are continuing to ask our customers to help by saving water, which can make a real difference.

“However, the weather remains one thing we cannot control, which is why we keep our water efficiency activities and messaging going year-round to remind people that water is a precious resource – whatever the weather.”

Recharge period

Meanwhile, SES Water says the recent heavy rainfall is so far not enough to “top up depleted water sources”. Whole services director Tom Kelly says: “Following a dry winter last year and the start of this winter seeing little rainfall, we are hoping for more of the recent wet weather to refill groundwater sources that have remained well below average for many months.

“October to March is the critical recharge period and autumn rainfall was very low – October was dry with only 35 per cent of long term average rainfall during the month, followed by only half of the expected rain in November. December was a lot wetter, but above average rainfall will still be needed from now through to March to minimise the likelihood of water restrictions in the spring.”

Thames Water is currently in a better position. Stuart White, media relations manager at Thames Water, says: “December’s rainfall has helped and we’re rapidly filling our reservoirs. We can’t be complacent though and will need to continue to monitor the situation very closely for the rest of the winter, particularly for the areas where we rely on groundwater sources.”

Ofwat’s Russell says the regulator will “continue to drive water companies to put resilience at the heart of everything they do”, and their performance, should a drought occur, will be carefully scrutinised to ensure the regulator can be confident in their ability to deliver long-term resilience.

Companies in the South East of England will be waiting nervously to see how much rainfall the winter brings. If there is enough – they’ll be saved. If not – another hosepipe ban could be on the cards. And all the while, Ofwat will be watching.