I was nominated as Scribe after the talk was over, and as I am only relying on a "mature" memory, any details could be inaccurate.

At the time of our visit, the Geotechnics Department was in the throes of "reorganization", often a euphemism for retrenchment and we sympathized with the staff. However, in spite of their problems Jim Woodhaws and his colleague gave a very interesting talk on their trials, tribulations and successes. They were also involved with the London Ring Main (which finished under budget and earlier than scheduled).

I include a few items from their talk:

The unpleasant taste of some water

The particular water mentioned came from another supplier.

With old water pipes, deposits collect on the inside and react with the water, causing an unpleasant taste and occasionally sediment in the water. The pipes are in the process of replacement and tainted water should soon be a thing of the past. Ozone is now being used as a purifier and in some agricultural areas plants are being installed to remove the nitrate fertilizer lavished on the land by farmers.

It was pointed out that tap water conforms to standards not required for the bottled water industry.

Underground water levels in London

In Victorian times industry used water from aquifers, depressing the water table and when building took place this low level was regarded as the norm. However groundwater is no longer used, so the water level in London is now rising at 3 metres a year and continuous pumping is required to keep the deeper underground tunnels operational. This "grey water" must be purified before use, but water pipes are designed to funnel water into Central London and the infrastructure required to pipe water out-of-town for purification would be prohibitively expensive. Trial aquifers are to be sunk in the Royal Parks and the "grey water" will be used to keep gardens green and London fountains flowing.

Economical use of water at the Dome

The roof of the Dome is to be used for water catchment, it will be filtered and used in wash basins, toilets etc. Separate drinking water will be supplied.

Turkey

In the interests of diversification technical staff from Thames Water are involved in projects abroad and as we spoke an engineer was winging his way to Turkey. A large water pipe laying project had been progressing satisfactorily through a raised bank when a local road contractor removed the "toe" of the bank posing a serious slippage problem.

During the earthquakes at Izmit, the water pipes were not ruptured - the water supply was not contaminated and no epidemics occurred.

The earth dams in Turkey also survived – our local reservoirs have a clay core of about a metre, in Turkey the profile is the same but greatly scaled up shoulders with 100 metre cores. It was suggested that the Turkish dams were “over-engineered” , but as they emerged unscathed were they really over-engineered?

We inspected a collection of drills, core collectors and other large, heavy equipment and were then shown a sample volume from the 1880s, leather bound, gold lettered and about Elephant size (28" x 23" in old measurements) containing detailed maps of all services in the area. When the GLC was disbanded this coIlection of civic art was thrown into a skip - fortunately it was rescued and is now preserved by Thames Water - it is to be hoped that privatisation will not produce a repeat of this disregard for archival records.

Here is your chance to contribute to geological research. Please send your suggestions/comments to Paul. We will publish the results in the next issue of London Platform and on this site.