REGARDING the article 'Doubt over zig zag replacement plan as costs soar to £1.25m'.

The cliffs of Highcliffe consist of alternate layers of pervious and impervious (clay) material. Water is absorbed into the former, which in turn lubricates the clay and makes it slip.

The council engineers correctly came to the opinion that the quick development of Highcliffe had exacerbated the situation by creating rapid rain run off from all the hard surfaces such as roofs, car parks and roads etc.

There are schemes to stop the water invading the cliff face. This involved creating a deep vertical curtain which obstructed the water, which was then channelled safely away.

With the exception of the Highcliffe Castle zigzag, our cliffs are now at what is called the Natural Angle Of Repose, which speaks for itself.

There are basically three prerequisites to create this stability.

The first one we have mentioned already.

The second one is not to allow the sea to erode the cliff base. Those ugly revetments which have ruined our beach have done what they were designed to do, namely to build up the beach to prevent the sea encroaching.

Thirdly, the vegetation is essential. This absorbs the rain, thus preventing it soaking into the clay layers below.

Also backfill is never as good as the original ground. You can see at the east end of the area behind Arundel that there have been deep old excavations to build large manholes. This backfill has already collapsed.

Any proposal to rebuild the Highcliffe Castle zig zag path will necessitate excavation and backfill. It will destroy some vegetation and it will alter the discharge of rainwater. If this means soakaways are necessary then this will be opposite thinking to that which the council have spent 50 years preventing.

Perhaps we should plant a lot more vegetation at Highcliffe Castle rather than carving into the cliffs again for a new zig zag path.


Rowan Drive, Highcliffe, Christchurch