From the article:

Droughts are generally two-year events. A year of dry weather means water supplies are running out – that is what is happening now. Things really come to a head if the following year does not bring above average rainfall. That is when the shortages start to bite, with farmers unable to irrigate and households and businesses hit with sweeping restrictions. With reservoirs at record lows and stream flows exceptionally low, England is desperate for rain.

Forecasts indicate that by 2055 England’s public water supply could be short by 5bn litres a day without urgent action to future-proof resources, the equivalent to more than a third of the supplies available today. The effect on the economy will be profoundly negative. The thinktank Public First has estimated that the economic cost of water scarcity could be £8.5bn over this parliament.

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Water companies in England and Wales lose about 1tn litres of water through leaky pipes each year. The industry has said that about 20% of all treated water is lost to leaks. The water firms have pledged to halve leakages by 2050.

Meanwhile, the annual pipe replacement rate is 0.05% a year across all water companies: much of the sewage system in London, for example, has not been significantly updated since Bazalgette and his colleagues installed it in the 19th century.

No new reservoir has been built in 30 years despite significant population growth and climate breakdown meaning longer, drier summers during which the country desperately needs to store water. The reservoirs England does have are at their lowest levels in at least a decade, just 67.7% full on average. According to Dr Wilson Chan, a hydroclimatologist at UKCEH, “above average rainfall over several months is needed to ease pressures on water resources”.

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Was it the privatisation of the water and sewerage industry in 1989 that has led to this situation? England’s water system has been widely criticised, and privatisation has been blamed for a lack of investment in infrastructure. Some say this is owing to the water companies paying out dividends rather than using the money raised by customer bills solely for investment in infrastructure; others blame a privatised regulated monopoly system that has prioritised low customer bills over investment.

Experts have also pointed to the regulatory system. Water company drought plans compel firms to follow a series of steps before they can increase abstraction, taking more water from reservoirs, rivers and the ground to supply customers, beginning with reducing consumption (a hosepipe ban).