Almost 500 memorials in Norwich's cemeteries have been found to be at risk of toppling over, with council officers having to lay down nearly a hundred of them to protect the public.

Norwich City Council has been testing some 40,000 gravestones over the past two years, amid health and safety fears.

The main testing involved staff inspecting the memorials, followed by a hand-test to establish if the stones were in danger of falling over.

But they also used topple-testing equipment, where a force of 25kg was put up against the stone to deem just how unstable the memorials were.

In April 2012, the council advertised for two vacancies - paid up to £25,000 a year - to inspect graves.

And the council has revealed that just over 400 memorials have had to be staked in place to keep them stable, while just under a hundred have been laid down because they were deemed to be too dangerous to keep standing.

A council officer said the ones which had been laid down were usually crosses and other memorials with multiple jointed parts, which could not be made safe with stakes.

A spokeswoman for Norwich City Council said; 'Those that have been laid down will stay there for now, though there is a due process for removing them should we ever choose to or need to. This involves publishing notices on-site and in the press.

'It is the responsibility of the grave owner to organise, and pay for, necessary remedial works on any memorials that fail an inspection.'

While the work on the memorials has been going on, the council has also been carrying out a thorough review of what burial space was available in Earlham Cemetery, which dates back to 1855, as they looked to figure out where the city would bury its dead in the future.

They came up with plans which would see older sections of the cemetery used for what are known as natural burials – where human remains are buried in biodegradable coffins or containers in an area which creates or preserves a habitat for wildlife.

And council officers embarked on a survey to figure out just how many so-called 'common graves', which are graves which have not been purchased, are in the cemetery.

They wanted to establish how much space there was in those common graves - which contain up to four spaces for burials - which the council, as burial authority, could sell so other people's remains can be placed in them.

The city council spokeswoman said: 'Since the programme got underway, officers dedicated to this programme have discovered an increasing number of available burial plots.

'In terms of common grave spaces, our current stats show we have more than 40,000 available spaces.

'We can't be overly prescriptive about precisely how long this will last. But, based on current burial rates and trends, this number would be sufficient burial space for many generations to come in Norwich.'

Paul Kendrick, previously the city council's cabinet member with responsibility for cemeteries, said: 'Council officers have worked hard to adopt a professional yet sensitive approach due to the nature of the work involved.

'As the project progresses, that hard work is really paying off and the latest figures show we have enough space for generations of Norwich residents who would like their final resting place to be Earlham Cemetery.'

• Have you had to pay for a memorial to be made safe? Tell us your story by emailing dan.grimmer@archant.co.uk