More investigations

Saturday 18 January

It was another day of out and about, Roger, Michael and Dave started off by clearing along the down side fenceline on Winchcombe cutting. Walsh Construction were on site to open a trench for us to to install some extra drainage to stop the bank over-topping into the cutting should the rain continue. There was a site meeting with the consulting engineers at Gotherington to discus what option are open to us to stabilise the embankment slip to ensure that trains can start running again in March. After lunch we all headed down to Bridge 29 at Stanley Pontlarge to look at another site that has severe drainage problems. One of the drawbacks of the lineside clearance team clearing the embankments is that we can see the problems the the vegetation has been hiding. It's a win for them, but more work for us 😒

The geologist on site today took one look at the hill behind the slip at Gotherington and spotted that it has a dish shape signifying that there had been a very big slip long before the railway had been built. The remains of ridge and furrow agriculture still visible shows that the slip must have pre-dated railway, even pre-dated the middle ages! The core samples taken show that the embankment was built by the GWR directly on top of the ridge and furrow. This means that the embankment sits on alternating strips of clay and deep top soil on top of clay, the furrows channel rain water from the hill under the embankment; hence the instability. The bottom line being that embankment was built on unstable ground without anything to hold it in place. A multi-stage solution is being worked up, with only 7 weeks to service start stabilising the trackbed is the key concern.

Looking to Nottingham Hill from Bridge 37 

Engineers on the slip site 

Gotherington slip face 

The toe drain chamber has disappeared 

Back at Winchcombe, the team tackled clearance of the down side fenceline to expose the filled in ditch over the crest drain 

Michael with the brushcutter 

Winchcombe Cutting up side, the emergency drains connected into the cess 

Digger opening a ditch for the crest drain 

New crest ditch excavation 

Roger and Michael head north
leaving the brambles for Dave
(Photo: Dave) 

The gang trudge back to the van for break
(Photo: Dave) 

Down side fenceline cleared
(Photo: Dave) 

Tree hugging
(Photo: Dave) 

Down at Middle Stanley and Stanley Pontlarge the trackside has been flailed to clear the vegetation. This exposes the ground and lets us see where potential problems are building. We checked from Bridge 30 to the level ground between Bridges 28 and 29. 

Starting at Bridge 30 looking towards Bridge 29 

Down side toe drain has been overwhelmed by the recent rain 

Stone topping on the drain scoured out round a tree 

Toe drain inlet in a bad way 

Arty shot through Bridge 29 

Bund on the bottom end of a newly created lake uphill from the railway 

Water ponding in the down side toe area 

Signs of flooding over the fence 

Dave trying to negotiate a way through the swamp 

Line to Winchcombe 

Up side looking to Bridge 29 

Up side after Bridge 29 

Culvert 30A up side, silting up 

We had a go at trying to define if Culvert 30A runs under the road or under the low mileage abutment of the Bridge 30. It may well be half and half. 

Tracing the line of Culvert 30A on the down side 

Bridge 30 from the up side, the abutment slope out 

Back at Winchcombe Carriage & Wagon have come up trumps again, we dropped the jockey wheel carrier from the flail in to the metalworkers this morning. This afternoon it's back fixed, the spindle has been welded back on. Thanks a million, departmental co-operation pays dividends 😊

Flail jockey wheel carrier welded 

Another bit of departmental co-operation, our brick arch former from Culvert 11A has found a new vocation in Winchcombe Yard, it was spotted being used as a signal post precision support. A truly versatile bit of design 😂

24" brick arch former but to new use 

Monday 20 January

Walsh were back on site at Winchcombe Cutting, the Isbourne work was still held up so we grabbed the opportunity to get the new 225 mm down side crest pipe plumbed in and backfilled. Steve was on hand with his tractor to bring some stone down from Stanton which made the job go even more efficiently. This left Dave, Nigel and Andrew at a bit of loose end, so they went up and cleared the drain channel above the tunnel portal. A 360 excavator arrived during the morning so that we can do some ditch clearance. In the afternoon we all headed off to Gotherington to measure up the slip. It's still on the move 😟 

Still a slight movement on the up side of Winchcombe Cutting, we'll keep monitoring it. 

Winchcombe Cutting up side the horizontal tree 

Dave poses at the tunnel to prove that they got there 😃
(Photo: Andrew) 

On the down side, the crest pipe along from the end chamber to beyond the gate was installed.  

Measuring up with the new pipe 

24" pipe down the crest, leaves no room to install the new pipe 

As there's not enough room to break into the chamber, it was decided to break into the pipe with the new drain. 

24" pipe exposed 

Tidying up the trench 

Hole cut into the 24" pipe to take the outlet from the new 225 mm 

Stub pipe tried for size 

Pipe bedding and top stone brought down from Stanton 

New 225 mm crest pipe installed 

Back-filling the new 225 mm pipe 

Wrapping the pipe in Terram 

In the field, it's clear to see where the water is coming in from, it runs down the field bringing silt in with it 

Surface water on the field next to the down side fence 

Down at Gotherington, the slip has moved further. Clear weather and frost make a change form the rains over the last 3 months  

Looking over to a misty Malvern 

Andrew with the measuring staff 

1.8 m ranging pole near the face 

The snout at the toe
The manhole has disappeared 

Culvert 17A up side, toe drain dribbling in from under the slip 

It looks like there may be a collapse in Culvert 37A, there is a hole under bridge 37 where gravel has been washed up above the culvert. Another job for the CCTV 

Bridge 37, possible culvert collapse 

Culvert 37A down side, toe drain running in 

Possible spring under the hedge on the down side opposite the slip