A town under siege by the sea: Since its beach was washed away, Withernsea on Humberside is cracking up from twice-daily poundings at high tide

THE HOUSE trembles. Glassware shivers on the shelves. The cooker shudders around the kitchen. Welcome to high tide at Withernsea.

Residents of this small Humberside town thought they were used to weathering the North Sea's worst excesses. But since February, when storms washed away the beach which absorbed the impact of breaking waves, they have been under siege by the sea: subjected to twice-daily poundings by the high tide - for four hours at a time - which are shaking up their lives.

The waves' force, as they strike the Victorian sea wall, can reach 120 tonnes per square metre. Locals liken the resulting tremors to a mini-earthquake - walls quiver, people are roused from their sleep.

Living on the Promenade, Lez White and her family are among the worst affected by the vibrations. 'The last few months have been absolute hell. It's totally dominating our lives,' she says. 'The earth really does move round here, not just on the front but a few streets back, and the big worry is that it will get worse in the winter.'

Last week Lez's cooker juddered around the kitchen. Mysterious cracks have started appearing in ceilings and window frames. ''It might not be the sea, but it's a hell of a coincidence.' As she speaks a shiver runs through the three-storey house. 'That was nothing,it gets far worse. It gets me down tremendously sometimes,' she sighs, drawing deeply on her cigarette.

Eddie Tebb, another Promenade resident, founded a residents' group to campaign for something to be done. He can remember 40 years ago when even high tides rarely reached the sea wall.

'It used to be great to sit snug in here when the weather was rough outside,' he said. 'Now it's frightening. The house feels like it's on jelly.

'Some of our critics say we are looking for compensation ,but that's not true. We bought this to stay here for the rest of our days. We just want it back to how it was.'

Although Eddie and Lez plan to stay put, other home- owners hoping to move away have been thwarted, their once- desirable seafront homes and businesses rendered unsellable. Some building societies are refusing to issue mortgages for properties on the Promenade.

Bruce Ryan, managing director of Frank Hill, a local estate agents, said Victorian three-storey houses which should sell for pounds 70,000 were effectively worthless. He recently valued a home for a retired couple further up the coast. Six years ago there were two fields between the sea and their bungalow. Now there is one. Mr Ryan believes the property may survive for 10 years before it is claimed by the waves. 'They've spent pounds 60,000 on it. They might get pounds 10,000 if someone wants a holiday home.'

Withernsea lies on Britain's fastest-eroding stretch of coast, running from Bridlington to the Humber estuary, where the North Sea eats away the soft boulder clay by between one and four metres a year. While Withernsea is protected against such erosion, the surrounding area is not and in 200 years the town could be an island.

Erosion is accelerating as climatic changes and geological movements cause an increase in sea levels which in turn generate greater wave power.

But erosion has an important function. Sand and clay particles from around Withernsea end up on marshes and mud flats in the Humber estuary, preventing floods inland. Slowing erosion by building sea defences creates a cycle whereby less sediment is deposited and more land needs protecting against high water levels.

The Minister of Agriculture, Gillian Shephard, acknowledged the complexity of the issue last week when she announced the Government's coastal defence strategy.

She said: 'Natural river and coastal processes should only be disrupted by the construction of defence works where life or important natural or man- made assets are at risk . . . intervention at one point can cause problems elsewhere.'

The definition did not go far enough for Dr John Pethick, director of the Institute of Estuarine and Coastal Studies at Hull University. He says the concept of 'important assets' needs to be quantified and that a debate is needed on whether money would be best spent on sea defences or on compensating people for moving from eroding areas. In the interim, he agrees that centres of population must be defended.

In Withernsea, work will start next month on apounds 1.9m coastal protection scheme to restore peace to the Promenade. Boulders will be piled next to the sea wall to form a slope, forcing waves to break away from the shore.

Eddie Knapp, principal engineer for Holderness council which is overseeing the work, is optimistic that eight months of vibrations will not permanently have affected homes on the front.

'Preliminary findings of a seismographic study suggest it's unlikely that any structural damage would have occurred. There's quite considerable nuisance value - we have appreciated that from day one - but we have done our best to try and get over that.'

(Photograph and map omitted)