Michael Gove has backed moves by the Environment Agency to force Southern Water to cut the volume of water that it abstracts from the River Test by 40 per cent.

The environment secretary has directed the agency to change the abstraction licence for the Test, one of south Hampshire’s main sources for water.

The decision was referred to Gove after Southern objected to a notice it was issued by the EA in 2017, outlining the revised licence conditions.

Under the new terms, the quantity that Southern can pump out of the chalk river will be capped at 80 million litres (Ml) per day, compared to the current maximum of 136 Ml.

The annual limit, which covers the Test below its tidal water mark, will be 29,200 Ml, and new caps will be imposed stipulating when abstraction is banned because flow levels in the river are low.

Until March 2027, abstraction will be restricted if flows are at or below 355 Ml per day at test points used by the agency.

The tightened restrictions on abstractions are designed to protect the Lower Test Valley and Test River sites of special scientific interest.

Responding to the new licence, Southern’s director of risk and compliance Alison Hoyle said: “The licence changes are challenging, Hampshire relies on these rivers for drinking water and new limits mean finding fresh resources.

“We’re planning to invest more than £800 million in schemes over the next ten years, including a desalination plant and pipelines to enhance the regional grid so we can import more water from neighbouring areas.

“It’s absolutely right that we protect our precious chalk rivers so we are also investing to create and protect habitats, especially for key species such as the Southern Damselfly.

“In the meantime, we are helping our customers become more water efficient by increasing the number of home visits to fit water- efficient devices and investing an extra £2.4 million in leakage detection and repairs.”

Speaking at the annual Waterwise conference in London yesterday (19 March), which focused on water efficiency, Sir James Bevan chair of the Environment Agency suggested more desalination plants will have to built.

“And most controversially of all, we will need to build new reservoirs,” he said.