It's going to be tight

Monday 17 February

There was time to catch up on a small job this morning; replacing the the manhole cover on the biscuit at Culvert 35A, near Gotherington Signal Box. To get the kit there we needed a a trolley and non-running season is a good time to get a possession to get round there. We had a quick check on the slip at Bridge 37 on the way. There was slight issue with keys today, which added to our travelling and walking. When we opened 35A up side chamber there was a fence post hiding in there, that proves the culvert is working 😃

After Gotherington it was round to Gretton to remove a pole stay from the end of the tunnel, remove more drain blocks and start reinstating the up side edge ditch from Culvert 24C up towards the tunnel. Busy old day 

Bridge 37 Gotherington, up side slip on 30 November 2019 

 Bridge 37 Gotherington, up side slip on 17 February 

Bridge 37 up side slip face, old concrete fillet dropping out 

Bridge 37 up side slip, creeping towards the track 

Bridge 37 up side slip, snout on the toe 

Over on the down side, there is some water coming in under the hedge, but it is soaking into the toe drain. 

Bridge 37 down side toe 

Culvert 36B inlet end 

The sun was shining this morning as we trundled round to Culvert 35A

Woolstone Hill in the sun 

Nigel and Dave with the trolley 

Culvert 35A up side, displaced manhole lid 

Culvert 35A - strange place for a fence post 

Culvert 35A up side biscuit cleaned up for lid fixing 

There was an unexpected opportunity to check the other ends of the culvert while Nigel nipped back to the truck for more equipment 

Culvert 35B up side 

Culvert 35B down side 

Culvert 35A down side 

Gotherington Station cess drain end chamber
with the point rod between the lids 

Gotherington Station drain, not much flow 

Gotherington Station 

Back at 35A the fence post was extracted and the manhole cover re-fitted 

Culvert 35A up side 

Culvert 35A up side with manhole lid secured 

Dave had to pop back to Gotherington to pick up some kit that was left behind, while there he spotted the equipment arriving ready to start the repairs on the slip 

Trucks in the distance dropping kit for the slip repair
(Photo: Dave) 

Round at Royal Oak some of the spoil from the viaduct had been delivered, this is for us to improve the turning area and haul road. 

Viaduct spoil for recycling into a haul road 

Royal Oak down side, still very wet 

Royal Oak down side, this area is hardly draining

Royal Oak, Nigel off to remove the pole stay
(Photo: Dave) 

Greet Tunnel - offending pole stay
(Photo: Dave)

Chopped off in its prime 😊
(Photo: Dave) 

Nigel removes some rusty pipe from the tunnel mouth
(Photo: Dave) 

It's not clear what the pipe was, bit the end has been removed
(Photo: Dave) 

The drain blocks are proving to be a bit of a mystery, the top blocks laid on their side are preventing the drain from working properly, alternatives to the blocks are being investigated. 

Top blocks coming out
(Photo: Dave) 

Royal Oak down side drain
(Photo: Dave) 

The drainage along this section has partly been mapped, the cess drains run to Culvert 24A which in turn runs out over the field and heads over towards Alderton. It eventually ends up in the River Isbourne and then the Avon at Evesham. 

Down at Culvert 24C the ditch running back up towards the tunnel is being reinstated. 

24C ditch outfall, seem to be a concrete post across the flow 

Bottom end of the ditch now flowing 

Steve delivers another load of spoil from the viaduct 

Random concrete recovered around the site for recycling 

Thursday 20 February 

Dodging the weather was the main activity today, Michael, Andrew and Martin went on a mission to recover items spotted on the lineside between Winchcombe and Toddington. A second team went to Gretton to lay a hard standing for the welfare cabin and to continue the ditch reinstatement. First a stop at Winchcombe cutting to see how the stabilisation works are going. The plan for the cutting has changed, instead of stone gabions 2.5 tonne concrete blocks are being lined along the cess to retain the slope toe. 

Concrete blocks for Winchcombe cutting 

Block wall being built up 

Winchcombe cutting up side slip 

Catchpit in the cess at the toe of the slope 

Out at Culvert 24C at Working Lane the base is down and work on the ditch is continuing 

Base for the welfare cabin being laid 

Boundary ditch that runs up towards Culvert 24B  

Ditch flowing into Culvert 24C up side 

The ground it really too wet for the machine, the ground is getting churned up. Our neighbour has requested the ditch is cleared as their land is getting the run-off.  

Ditch to Culvert 24C 

The requirements and design for the Royal Oak work was reviewed after lunch, this involved getting caught in a hailstorm 😠 The wind was blowing the weather fronts through at some speed. 

Looking over to Malvern as the storm blows through 

Storm blown through, sunshine at Malvern 

Water running down the surface of the down side slope 

Water rising rapidly after a cloudburst 

There's no reference available as to why the cess drains along a lot of the line have the hollow blocks over the pipe, the blocks laid flat on the top are inhibiting the work of the drain. Options being considered are; removing the blocks and backfilling with free draining stone, replacing the blocks with the eyes upwards and adding a surface covers that allow water to drain in. Next job is more investigation and costing. 

We had brilliant win this week, after a tip off we managed to buy a 8 pallets of drainage rings at an auction. Along with the rings was a couple of pallets of blue GRP catchpit covers. The overall saving from this purchase is in the region of £7,000. Now all we have to do is work out which station we are going start kitting out with the blue GRP lids - north to south sounds like a good idea 😂

Catchpit rings being offloaded 

Final tally - 72 concrete rings and 74 GRP lids 

Friday 21 February 

Flying visit today to see the start of the soil nailing at Bridge 37, Gotherington. The clock is ticking to the start of the season, it's going to be very close  

Traffic has increased along Manor Lane 

High strength cement used with the soil nails 

To get the drilling rig in a new haul road has been installed. 

Haul road along to Bridge 37 

Permeable membrane waiting for a covering of Type 1 

The nails going in will be 15m long and angled under the trackbed into the ground below the embankment.  

Drill rig installing the soil nails 

Crack in the slope getting bigger 

Bridge 37 up side slip face 

Drill rig with the soil nails 

Bridge 37 up side slip snout at the toe 

Up side slip toe 

The ground has sunk below the protruding sleeper in the face 

Crack on the slope 

There's signs that the slip has moved in the last 24 hours 

Shear where the slip has moved 

South end of the haul road 

X marks the spot - 3 rows of nails 1m apart 

First 2 soil nails in 

Soil nail end 

The 5 parts making up the 15m nail are the drill bit, 3 extenders and a galvanised extender for the surface end. 

Soil nail components 

On the way home time for a check on the gabion stone installed on the cess drain at Bridge 42, Southam Lane 

Bridge 42, Southam Lane, down side abutment no water pooling 

Bridge 42 wind blowing the weep water 

Saturday 22 February

Most of the activity today was round at Royal Oak, a bit of measuring, ditching and cess drain investigation. First off we cut the vegetation back on Winchcombe Station Platform 2 bay, Carriage & Wagon had asked us to get the brambles cut as they were a trip hazard.

Dieh raking the edge of the ballast in the bay platform 

Winchcombe cutting slip, the block wall is creeping along to the tunnel 

Round at Working Lane Dave was breaking up the old concrete into sections big enough to go to the scrap pile

Dave with the breaker
(Photo: Dieh) 

Dave and Dieh erecting the safety fence round the welfare cabin 

The up side perimeter ditch was finished off this morning.

Next length of ditch to recover 

Perimeter ditch reinstated 

Dave and Dieh took the levels for the design of the chamber to replace the headwall on Culvert 24B up side  

Dave heads up the hill 

Dieh and Dave measuring up at 24B down side 

The fence line at 24B, in need of stabilisation
(Photo: Dave) 

After lunch we all headed up to to take the down side cess drain apart to see how it had been constructed so that we can formulate how to improve it's working. The toe of the cutting slope has always been wet along this stretch, the reeds, peat and moss are testament to the level of ground water. 

Royal Oak down side cess drain
work in progress  

Second row of blocks removed to expose
two courses of dry fitted bricks 

Clearing the base to expose the pipe 

Dave and Dieh excavating the catch pit end 

Close up of a non-working drain 

Schematic of the drain composition 

The issue with the drain here, and probably at other locations along the track (Southam Lane in particular), is that the drain isn't efficient. The 9" x 9" x 18" hollow blocks may have been an economic way of constructing the drain, but the only route in for the water is to seep through 4" of concrete. It can't get in from the top or the sides as there no gaps big enough for the amount of ground water. That's why the blocks and unused down side trackbed have got covered in decomposed vegetation and fines washed down, this has just exacerbated the problem. 

Once in through the blocks the water runs into the pipe through the open joints between the SGW pipes. These joints have blocked up over the years with the black silt that has leeched in through the odd crack. 

What's the solution, one possibility is to remove all the blocks and backfill with free draining stone and permeable membrane. Whether we need to do the whole 300 m of the drain is being questioned. Costed proposals will be developed next. The crest drain that runs parallel to the cess drain should be collecting the flow as it runs down the hill and under the fence, but that's overgrown and and not working at peak efficiency either. More excavation and free drainage stone required. 

As usual, the project has grown in both effort and cost, you will soon need binoculars to see the end milestone as the plan shoots off to the right 😊

Ebbw Vale 3 hole Type 2 bricks under the hollow blocks 

A quick search shows that all of the four the Ebbw Vale brick works closed in the 50's and 60's. That doesn't help us date when the drain was installed. Possibly in the late 1940's when they did the other end of the tunnel. 

End of the day 

Blast from the Past 

The drains on the Winchcombe side of Greet tunnel and through the station were upgraded in 1949. The following pictures, kindly supplied by Nigel Newling after reading one of the previous blogs, show the work in progress. These were the days before the ubiquitous 360 that is now the mainstay for this sort of work. 

We aren't sure if this was when the drainage was installed or just upgraded. There's no sign of any old pipe being removed. There are a lot of hollow blocks scattered about the cutting slope 

Winchcombe Cutting up side drainage works 

Ruston Bucyrus RB-19 face shovels 

Drain blocks! 

Through Winchcombe Station 

The finished job 

Note how the tops of the hollow blocks are exposed and the catch pit lids are the only thing above the level of the blocks. Over time the blocks have been covered and the pits raised.