Part of a busy supermarket petrol station has been shut down because it has started to sink into the ground.

Eastern Daily Press: Longwater Sainsbury's petrol station where part of it has been fenced off due to subsidence. Picture: Denise BradleyLongwater Sainsbury's petrol station where part of it has been fenced off due to subsidence. Picture: Denise Bradley (Image: copyright: Archant 2014)

Sainsbury's has called in structural engineers to assess its fuelling station at Longwater Lane, near Costessey, after having to close five pumps due to subsidence.

Eastern Daily Press: Longwater Sainsbury's petrol station where part of it has been fenced off due to subsidence. Picture: Denise BradleyLongwater Sainsbury's petrol station where part of it has been fenced off due to subsidence. Picture: Denise Bradley (Image: copyright: Archant 2014)

The grocery giant confirmed it aims to keep the site open and it is safe for customers to use.

Eastern Daily Press: Longwater Sainsbury's petrol station where part of it has been fenced off due to subsidence. Picture: Denise BradleyLongwater Sainsbury's petrol station where part of it has been fenced off due to subsidence. Picture: Denise Bradley (Image: copyright: Archant 2014)

But it has posed questions about whether the petrol station will continue to remain open in the long term. It is understood the problem could be caused by the pressure of heavy lorries passing by on the A47.

'We've temporarily closed a number of pumps at the petrol station while we carry out investigations with structural engineers,' a spokesman for Sainsbury's said.

'The site is safe to use. We're keeping it under review and we're considering options for a long-term solution.'

Sainsbury's agreed to buy the 10-acre site on at Longwater in May 1996.

The 60,000 sq ft Sainsbury's store, designed and built by RG Carter, was completed in record time – 27 weeks from land purchase to completion. It opened on March 5, 1997, welcoming more than 4,000 customers into the store on its first day.

Meanwhile, in 1997, the retail park next door to Sainsbury's was bought by Legal & General for almost £30m, before being developed into an out-of-town shopping centre site.