Some 5,000 buildings in the heart of Groningen’s earthquake zone need to be shored up immediately, the Dutch mines inspectorate has told economic affairs minister Erik Wiebes.

In addition, steps should be taken to reduce the volume of gas extracted from under the province to below 12 billion cubic metres more quickly, the inspectors say. Measures to stimulate this, they said, could include a ban on the use of Groningen gas by large industrial users.

‘The reduction in gas extraction and strengthening buildings is key for the safety of Groningen,’ the inspectors said.

However, previous calculations on how many houses need shoring up were based on a far higher volume of gas being removed. Now production is lower and will be cut still further, fewer houses need to be strengthened, the inspectors say.

This includes the 3,000 homes which Wiebes earlier said would not be worked on until the impact of the cut in gas extraction had been properly assessed. Just 10% of them are now thought to be at risk.