Challenging. Breach 36. 30th March

This morning another update from C&RT.

Update on 30/03/2021:

We have experienced a few challenges with the coffer dams at the breach site during the weekend. 

To help manage this we have had to drop levels between Ferrybridge and Pollington, therefore fluctuations in water levels may be experienced over the next few days as work continues at the breach site on the long term repair. 

Skippers of all craft are advised to check their mooring lines to ensure their vessel is securely moored allowing for water fluctuation.

We apologise for any inconvenience this may cause. 

Levels had been overtopping the cofferdam at the western end over the weekend. The prevailing wind not helping. A video from Lisa shows the extent of this. Finger credit to Lisa.

The Aire and Calder appears to have no spillway between Ferrybridge and Goole unlike most canals. Spillways help to keep the level of a pound at a certain level or below, but the spillway to this pound is the docks in Goole which when ships are coming and going with the tides works pretty well. But now the cofferdam is in the way water needs to be pumped round it to supply the docks with sufficient water and to help keep the level above the cofferdam at a suitable height.

This all means that it is a bit of a balancing act to keep the levels at suitable heights for all. The levels in the docks for ships to come and go. The moorings in the docks. The moorings at Rawcliffe Bridge. Low enough not to overtop the cofferdam. Above the cofferdam the moorings below Pollington Lock.

Ferrybridge where there water can be let into the canal from the river

Levels seem to get dropped all the way to Ferrybridge, which suggests that this is the only place where they can control the amount of water coming into the canal. Tracking Google maps towards the breach there may be one sluice above Whitney Lock where the level could be dropped, but this goes into a drain rather than a river, so could end up flooding fields.

The height of the cofferdam seems to be an issue that comes and goes. They are planning on raising the level of the piling at the eastern end, handy as that is where the work pontoon is. But will they be able to do the same at the western side? Do they need to do this or will they be able to keep the levels upstream managed sufficiently to stop it overtopping? Or will another pontoon be required at that side to raise the piling?

Good news elsewhere is that the works on the breach near Hack Green on the Shroppie are nearing completion, the area was being filled with water yesterday. Well done C&RT, just wish they had been as successful on the Aire and Calder.

*Post update Mark has been out again with his drone today. Good news is that the cofferdam has emptied itself again.


There are more photos, so I’ll write more in the morning as it’s time for food now.