Sinking driveway

Hi,

Posting on behalf of my neighbour. He is experiencing 'sinking' in his block paver driveway. Interestingly, in the vicinity of two manhole covers. He had the area surveyed with cameras in the pipe runs and remedial works done about two years ago but found nothing.

My thoughts would be cracks in the drains and sediment running into them and away. Any other thoughts or options? We live on a clay substrate which does cause heaving and sinkage depending upon prolonged drought or rain. Also, we are near a railway and can feel the vibrations in the house.

TIA

Or a leaking drain washing the ground away.

What remedial works did they do?

RrogerD, good evening.

I am with last post by Ian H,

As an aside? this could be an Insurance claim, under the heading of "Accidental damage to an underground service"

Could be that the original "repair" was not undertaken correctly? or simply bodged?

Heave in this situation is not happening.!

Ken

It is perfectly normal for the ground around an IC to settle in this way. Firstly, it is all disturbed ground around that IC that has been put back. Secondly, the IC will likely be on a concrete base and unlikely to settle any amount. Some folk compact (in deep excavations) as they go others don't.

RrogerD, good morning again.

Have you considered a mains water pipe leak ?

Ken.