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The Ace hole


Belonging to Thames Water

Saturday 6 March 1999

Disaster! At about 11 o' clock this evening, a water main burst destroying the car park and taking out my favourite 1982, 650cc Meriden built Triumph Thunderbird.

Big Ron and I were in the car park when it happened. We were chatting when we heard a roaring noise. It was followed by rippling in the tarmac - like air under a bed sheet - and a great ripping sound.

There was an explosion and the asphalt stood up in front of us. A bright white column of water shot from the ground just feet away from us, throwing great chunks of rubble into the heavens - along with my T-bird. I legged it.

In seconds, the car park was over a foot deep in water with lumps of rock whizzing about our heads. The whole building was shaking and you could hear windows breaking and lumps of rock crashing on to the roof. I took everyone up the stairs and out the back fire escape. We all met up on the roundabout and phoned the fire brigade. We were totally soaked. Looking back at the cafe you could see

a huge fountain of water, maybe 20m high, and it was getting higher and higher.

At about 11.15pm, the first fire engine arrived followed by the police. Soon after, an engineer turned up from the Three Valleys water company. He had to phone his supervisor to find out if it was the company's main. It wasn't. I could have told them it belonged to Thames Water, but no- one asked me. In fact, no-one spoke to any of us. We just stood shivering and watching by the roundabout, arguing over who had any dry fags.

Thames turned up in the small hours of the morning. No-one talked to us at any time to give us an idea of when the water would be turned off or when we could get back to secure the cafe and get our bikes. Eventually, at about four o'clock, shivering and fed up, we all made our own way home.

It seems strange that nobody spoke to me at any time.Having seen exactly where the burst happened, presumably my information would have been useful.

Sunday 7 March 1999

Water was still pumping out of the ground when I arrived at the cafe at about eight o' clock this morning. The underpass was flooded and our bikes were floating around the car park completely written off.

The fire brigade were there in force, pumping water into the River Brent behind the cafe. Looking along the river, you could see hundreds of hoses whipping round like angry spitting snakes.

The police were into big time traffic management with the North Circular out of action. I was anxious to get in to check on the cafe and make it secure, but

it seems individuals directly affected by the burst are not considered a priority.

Thames were bringing pumps from the length and breadth of the country and you could see the column of water reducing in height through the day as the pipe was closed down. The flow was stopped by mid afternoon.

Thames' contractor TPS arrived around midday. Once the water was pumped out of the hole it started excavating the burst pipe.

We were warned not to go across the car park to get our bikes because the engineers were worried about its stability. They said there could have been a huge hole under the tarmac. But once TPS cleared debris from the crater you could see that the blast had been upwards.

I warned the Thames Water engineer about the vulnerable Victorian brick sewer under the car park. He said it wouldn't be a problem. I don't know how he can have been so sure. HGVs have been banned from going across it for years yet they were using heavy plant and a very large wheeled excavator.

I saw a circular hole in the main with crystal clear water coming out. The lid was lying upside down and covered in mud about three feet away from the hole. There were bolt studs around the hole and these were much longer on one side than the other. Blocks of concrete that had once covered the lid were spread around the hole. They were heavily stained with rust.

TPS was helpful and kept me informed. Unfortunately, Thames was not so helpful. It was too busy being pleased with itself because it managed to get the burst under control.

Some of the guys working in the crater reckon the main must have been leaking for ages judging by what they saw. The senior people from Thames, however, are going through a right song and dance to say otherwise.

Monday 8 March 1999

The pumping continued throughout the day. The fire brigade told me it was lucky it happened where it did because it had an emergency action plan already in place in case the Grand Union Canal over the North Circular was ever blown up.

Wednesday 11 March 1999

Thames has done a marvellous job getting rid of the flood. And in the last few days it has put a new lid on the main and filled the crater.

Now it has got people going over the lorry loads of debris that were taken away with metal detectors to try and find the bolts from the burst lid.

There are new cracks in the cafe walls. I have asked an engineering firm called Ellis & Moore to investigate. It is my guess that leaks from the main may have caused cracking.

Ellis & Moore installed strain gauges many years ago to monitor cracks in the walls after some appeared following work on the river behind the cafe. When I bought the place in 1997 it conducted a survey and told me the building had not moved since 1991.

Saturday 13 March 1999

Thames sent another contractor to resurface the car park today. But I am concerned it has replaced one of the gully drains with a pea shingle soakaway. It seems clear to me that the ground in that area was already saturated before the burst. That area had sunk before the burst and the grate sat about an inch proud of the surface.

Monday 15 March 1999

Ellis & Moore says that there are new cracks and claims its strain gauge records show the hairline cracks to have widened. It has also suggested further investigation including boreholes and inspecting of the drains with closed circuit television.

Saturday 10 April 1999

I don't know whether to laugh or cry. Thames has told me it is going to investigate two more hatches in the car park similar to the one that burst after discovering it was bolts that failed. This means digging up the car park - newly laid.

It seems like I have another leak. Thames has told me that the clear water leaking out of a vertical joint seal in the river is chlorinated. Also, two weep holes in the wall are leaking. The fact that others aren't suggests the water is probably coming from a specific source.

Monday 26 April 1999

Thames was on site today digging up the two other hatches. The first one it exposed was close to the one that burst. It is sitting in a mush of watery mud and is a rusting mess. Thames is being very guarded about it.

It then exposed another at the other end of he car park. It appeared to be in good condition encased in bitumen with no sign of excess water.

The workers told me they had to reduce the pressure in the main to be able to work safely. I noticed that when they did this the leaks from the river wall reduced significantly.

Wednesday 12 May 1999

Thames is back on site to carry out soil tests. It has marked out a big grid on the car park surface and has drilled holes along two of the rows.

I asked what it was investigating but it has not told me. I have asked my surveyor Addison, Lovett & Lord to request this information in writing.

Monday 31 May 1999

My lay conclusions have been vindicated! The Ellis & Moore investigation backs up my suspicion that damage has been caused to my building by leaks from the water main.

The Verdict

Wilsmore's experience after the flood has left him feeling bitter. And while his view on civil engineering is fairly neutral (he feels his battle has been with a company trying to protect its public image rather than with engineers), he has formed some fairly strong views about civil engineering maintenance regimes.

'It is clear from the scale of the eruption and what followed that Thames was unaware of the nature and condition of its pipe before the burst. This has to be a worry given that it is one of the most important mains in London. Questions have to be asked about its monitoring and maintenance regime given that the hatches on the pipe appear to have been completely overlooked.

'You have to constantly monitor and maintain a motorbike otherwise small faults become big problems. It must be the same with water pipes. But who is looking at this? Who monitors this industry?'

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