As of last night, (11 March) the coffer dams were removed, and it is possible to get on to the Worcester and Birmingham from the BCN.
Having put the coffer dams in, C&RT set about pumping out the water.
Come Sunday morning and the fish rescue started. There was an amazing number of film crews and photographers about (including me).
The weather was definitely damp. I think the guys in the canal were probably the driest people there!
Fish rescue complete, the pumps turned off, waiting for work to start on Monday.
Midnight last night (19/20 Feb), it was clear that the pump was not coping with the leakage in through the emergency stop gates. I was told that the plan was to stanch off the section from Worcester Bar almost to Salvage Turn.
This morning, the work started on the coffer dam.
Though those guys are in decent dry suits, rather them than me.
In addition to the pump in the workboat just behind the stop gate, there are now two larger pumps beside the footbridge, ready to start go.
To clarify exactly where the aqueduct / tunnels are, I have taken a photo of the 1899 10 foot to the mile ordnance survey map, and marked out the two rail tunnels (the one to Midland Railway’s Worcester Wharf goods yard, the MR Birmingham and West Suburban line (the current main line to the West Country) and Holliday Street tunnel.
Isn’t the detail on maps of this scale amazing! Click on the image to see it in more detail.
The frames were left in, to be completed on Saturday.
Having moved the boats that wished to go out of the Worcester & Birmingham side of the basin, the next thing was to shut the emergency gates, in preparation for pumping out the cut.
The tug came up from Granville Street bridge, and closing the emergency gate would only take a moment.
Snag – though the gate in the Worcester Bar had been checked this morning, it certainly wasn’t moving now.
Get a bigger hammer!
Across several hours, from about 16:30 to 21:30 and continuing – the gate has been moved about a foot!
Still, the pump is ready to go as soon as the gate is shut. It looks like being a long night for some.
The buzz went round this afternoon that the Worcester Bar was being shut as an emergency measure, because of a leak in to the disused rail tunnel that used to carry the LMS line from what is now Five Ways station to the old goods yard.
Network Rail (who apparently own this aqueduct) were working on the tunnel, and when they returned to work decided that there was more water in the tunnel than there should have been.
So the emergency gates at Worcester Bar and Granville Street Bridge will be closed as soon as they have moved all of the boats out of the W&B side of Gas Street Basin.
The water will be pumped out as soon as the gates are closed, though the pumping will not be completed today, to avoid the need for a fish rescue. If this level of drainage does not reveal the problem, it will at reduce the risk, with a big drop in water pressure, (and I suppose a lot less water to get out, in the event of a failure occurring despite the reduced water pressure)
Definitely high profile interest – Richard Parry was there within hours of the start of work (mind you he does get pretty much everywhere!) along with two of the senior engineers. One of them even had her assistants! Sod’s law that things like this happen over half term. Despite being on leave, she had come in to help with the work.
As there is no feel at the moment what the scale of the problem is, there is clearly no indication of how long the emergency stoppage will last for. An interesting possibility is that the water coming in to the tunnel is not necessarily from the canal but may be from a water main. However with 38 miles of canal to drain in the event of a breach, they are not banking on that.