Not only this but the whole city is sinking..... by using satellite imaging it was showed that over a 2½ year period between 1993 and 1995 a large portion of Stoke-on-Trent sank by up to 80mm - this is the equivalent of the effect of a major earthquake!

The Etruria Works on the Trent & Mersey canal - 1898

The same works - c.1930's

Subsidence of Wedgwood's Etruria factory

  The two photos should be compared - by the 1930's there is now a railing alongside the canal footpath and a slope down to the factory frontage.

  on subsidence of Wedgwood factory

Evidence of Subsidence in Stoke-on-Trent
1844 court case on mining subsidence

Lord Granville owned coal mines which extended under, among many other areas, Shelton. When mining for coal supports were left to try to prevent collapse of the mine.  

Around 1833 Granville stared to mine for iron-ore. The method and economics of iron-ore mining meant that no support was left and consequently large scale damage was done to houses above some of the workings.

In 1844 a Mr. Hilton, who lived in Union Street, Shelton, brought an action for compensation (he was supported by others in the same predicament) against Lord Granville.

Granville admitted that his mine works had caused the damage.

on the 1844 court case

16th June 1857 - Staffordshire Advertiser newspaper.

"Inundation of a coal mine:  A singular and fatal casualty occurred on Monday afternoon, at a colliery at Cobridge, on the estate of the Misses Adams, by a portion of the bottom of a fish pond giving way, consequent on the mining operations being carried on too near the surface. Immediately under the fish pond are some old workings which events have disclosed had been worked up to within about five feet of the bottom of the pond, and where a man was employed that morning in getting ironstone.... Mr Tinsley (who, with Mr Samuel Fox, rented the mine) was drowned, his body being discovered about an hour after the accident...." Note: there were 11 men and boys in the pit at the time, working on two levels. Mr Tinsley was one of 3 on the lower level, only 11 yeards from the bottom of the shaft.

Newspaper articles

differential interferogram of Stoke-on-Trent
- over a 2½ year period -

The interferogram is overlaid over a satellite image of the area

The fringes represent recent ground movement over a period of almost 2½ years, during the years 1993 to 1995. 

8 cm subsidence over 2½ years:
Over this period, the satellite survey found that the centre of Stoke-on-Trent sank by about 8 cm. The subsidence extending for 5 km (East-West) and 10 km (North-South).

We do not have to look very far for a reason for this ground displacement. Subsidence over underground coal workings has long caused problems in the conurbation, although there is no complete survey of the hundreds of workings. 

There is an unusually thick sequence of Coal Measures in the region, with 52 individual seams from 1cm to 3.5m thick occurring over 1100m of rock succession dipping gently beneath the conurbation in a deep trough. 
 

By superimposing the fringe contours over the geology map of the area, it was noted that 30 of the 52 coal seams occupy the fringe core. These seams trend north-northwest, exactly parallel to the strike of the core of fringe pattern. This "grain" is shared by the strike of the geological strata, the topography (there is a height range of 80m to 100m across the core of the fringes) and the trend of minor landslips, along steeper slopes where harder sandstone outcrop. These landslips, the largest about 1km long and 150m wide, are nowhere large enough or consistent enough to result in displacement adequate to yield a fringe.

The stacked coal seams reach the surface to the east of, and within, the core of the fringes. They dip westward, mostly consistently, at 10° to 20°, beneath the core of the fringes. The generalised sub-surface distribution of these seams in the geological section shows a coincidence of stacked seams and the fringes that is so strong that this is unambiguous, if circumstantial, evidence for subsidence of the coal workings.

There are an estimated 8000 disused shafts in the Stoke-on-Trent conurbation and at least 200 abandoned adits within the area defined by the fringe patterns. There are almost no active coal workings in the area and none whatsoever within the fringe core. There is a very close coincidence of the fringe contours and the outline of the areas of all underground coal workings and, displaced updip (that is to the east), the area of mine workings within 30m of the surface. Many of these workings are ancient and predate systematic survey and recording. As there are only piecemeal survey of these workings, sudden unexpected collapse over mining voids or over areas where the pillars of the old seams, or the mouths of shafts collapse, are a feature of the whole conurbation. 

The subsidence demonstrated is at relatively shallow depths, probably no more than 100m and maybe no more than 30m depth. Extensive underground shafts, "bell-pits", adits and workings, many by pillar and stall (in which pillars of coal are left standing, usually on a rectangular grid to support the workings) underlie the whole conurbation. Mining has been almost totally abandoned, and collapse of roof supports and pillars in particular, and seasonal water logging is causing subsidence.

on the satellite survey