The riddle of the gas pipe

Week ending 31 October 2020  

Where has the year gone, it's autumn already and with another 4 weeks of Lockdown just announced it looks like that'll be it for the rest of the year. No major projects this year, just jobs on hold. 

Monday saw Dave and Nigel down at Bishops Cleeve to clear the ditch on the downside crest where the silt has contaminated the ballast. 

Report and pics from Dave... 

Down side cess, silt contamination 

There's a fungi ecosystem in the ditch, the wood has been in there so long it's sprouting things you'd only find in gourmet restaurant 😕

Brown fungi 

White fungi 

The ditch is starting to look clearer, it could do with a an excavator running along to remove all the lumps and bumps. 

Down side crest ditch 

600mm pipe in the crest 

Water flowing away 

Progress so far

Still a way to go 

The Thursday team were in the Gotherington to Greet section doing more jobs on the To Do list, it always ends up with some more being added though. They started off at Gotherington Yard on Culvert 33B 

Report and pics from Andrew... 

Culvert 33B up side headwall 

Culvert 33B exit stream cleared of debris 

Culvert 33B down side inlet 

Then up to the three arch bridge at Dixton (Bridge 33) where a load of scrap was collected from under the down side arch... 

Scrap from Bridge 33 for disposal 

All clear under the arches now 

Next stop was Culvert 28A, Tirle Brook, which runs across the middle of Dixton Cutting, again this was clearing the bed of the stream 

Culvert 28A Dixton exit ditch 

Culvert 28A Dixton exit ditch 

Root embedded in Culvert 28A inlet stream 

Another Roger Holloway head slab 
on a land drain at 28A 

Culvert 28A down side inlet flume 

Culvert 28A concrete headwall, up side 

One the way up to Gretton Culvert 28A was checked and the silt removed from the up side chamber in the adjacent field 

Culvert 28A silt deposits 

Last job on the way out at Manor Lane was clearing the grille on the outlet pipe on Culvert 24C. This always blocks up at this time of year, it's the leaves  

Culvert 24C up side outlet pipe 

Culvert 24C up side outlet pipe after raking 

There's been a gang out at Verney Junction near Milton Keynes retrieving some imperial engineering bricks from a disused platform that is being demolished to make way for the East West rail connection. Andrew has been with them for the last 2 Saturday's doing a bit of overtime. 

Bricks ready for shipment to Winchcombe

2 of the Verney bricks sandwiching in a GWR blue 

Friday was a game of 2 halves, first stop was Bridge 29 to reconstruct the wing wall and stick the coping back on the down side parapet, this was after Roger had cut up all the scrap bits to make enough for good end... 

Stanley Pontlarge, leaves almost on the line 

Bridge 29 down side parapet cleaned off ready for coping 

Roger puts the coping puzzle together 

Bridge 29 down side parapet, good as new 

End coper, nobody will notice it's in 2 halves 

The end of the low mileage down side wing wall has come adrift, so while we are here it can be reconstructed 

Bridge 29 low m d/s wing wall 

Cleaning all the crud out ready for building back 

Wall rebuilt and left to dry before adding the large coping stone 

On the way through Dixton Cutting we stopped off to replace a broken top on chamber, it turned out to be a bit of a pre-cast grit bin side so it's no wonder it cracked under any weight 

Dixton up side cess, cracked chamber lids 

6 home made 900mm lids installed 

After lunch, the focus moved to Bishops Cleeve and the reported silt in the down side ballast. The cess drain along here is another of the concrete block constructs, hopeless for letting water in. The clay washed down had built up on top of the blocks and stopped anything penetrating.

Stuart clearing the blocks at the south end 
(Photo: Roger) 

Roger clearing the block tops 
socially distanced at the north end 

The cess pipe is 3 feet down 
below the top level 

The depth of the cess pipe doesn't help drainage. All the blocks will need to come off at some stage and be replaced with free draining stone or soakaway crates. 

Up on the crest the void under the pipe was measured at approx 2 cu mtrs, it's 4 feet deep! the clay has washed away somewhere, we didn't take 2 cubes off the top of the cess. This may well turn out to be another rather large job. 

South end of the void 

Outlet from the void at the N end 
(Photo: Roger) 

One of the operatives (no names, no pack drill 😉) dropped his mobile in the hole while taking a picture...  

Mobile phone extractor device in action 
(Photo: Roger) 

Cleeve cutting down side slope 

Now we get to the mystery, there's a gas marker post laid in the toe of the slope, and legend has it that there's a redundant iron gas pipe running down the slope. Can this be true, why would a gas pipe run over the railway here. Up until the railway closed towns were on Town Gas (i.e. Locally produced), the gas works in Cheltenham was on Tewkesbury Road. Would it have been worth running a pipe to Bishops Cleeve which was a village at the time, and even if they did it would have been cheaper and simpler to run along the A435 Evesham Road. 

Gas marker post, is it red herring 

Star marks Cheltenham gas works, with Bishops Cleeve in the 1950's and Cleeve now 

Could this pipe have been misidentified and in reality be an abandoned siphon culvert. There's another siphon 4 chains north picking up a smaller stream (Culvert 40A).  

Ariel image Bishops Cleeve Cutting
Copyright Google Maps 

It's all a bit of riddle at the moment, the mystery pipe needs to be located and uncovered and that'll shed some light on the case. It's hard to believe that the GWR would have expected a stream to run round a right angle bend into ditch. Meanwhile enquiries will be made with the utility provider. A consulting engineer has been called in to asses the stability of the slope and advise on what remedial action is needed. 

Watch this space for further development, although with lockdown intervening it may be a while before it gets sorted out 

Stay safe out there or as Phil Esterhaus would say, "Let's be careful out there." (Now rack your brains over where that came from 😆) 

Tell me about ditches

Week Ending 24 October 

This week started off with a report from Permanent Way to say that there has been water running down the embankment slope south of Bishops Cleeve for about 2 years. This hadn't been been picked up because it wasn't adjacent to a culvert and the current inspection regime doesn't include ditches and areas away from culverts. On Monday Dave and Nigel headed south to investigate, they took some fencing materials to repair the fence next to the Pecked Lane foot crossing as they went past. It's called multi-tasking 😉 

Report from Dave... 

New rails on the crossing approach fence 

Pecked Lane foot crossing 

The water run off down the slope was to the south of Two Hedges Road bridge, the slope is covered in thick vegetation so the only evidence of the water is in the cess. There's a cess drain along here, but the crest ditch is supposed to intercept any flow. It's likely now that the cess drain permeable layer has been blocked with fines. 

Water running down the down side slope 

Silt washed out into the ballast shoulder 

Next job was to find out where the water was coming from, that meant scouting out the crest, where they found a 90⁰ bend that picks up the flow from a pipe and sends it along the crest ditch. The ditch at the end of the pipe had silted up and caused the flow to run back along under the pipe until it found a way to escape down the slope. 

Stream divert into the crest ditch 

Piped flow from the stream 

Mystery cavity under the piped flow 

More investigation is needed here to see what the mystery cavity is. The gang dug the end of the pipe out and cleared the ditch to reduce the flow down the slope. This is a historical problem, there's no record of how long the plastic pipe has been in the crest, but there was some work carried out here in January 2016. This was to remove a blocked 6" plastic pipe that had been buried in the base of the slope and run to a cess drain.  

Pipe still in the crest ditch in 2016 

Andy P surveying the blocked plastic pipe removed in 2016 

Alastair and Kieth opening the cess
to clear the flow from the crest in 2016 

After the pipe and crest ditch had been partially cleared,the flow diminished into the cess 

A bit dryer in the cess (back to the present)

A bit of digging required in the cess next 

Before setting off back, the turnaround area down towards Kayte Lane was cleared, this saves anyone getting stuck or having a long reverse back to the entry point. 

Cleeve south up side tuning point 

On Thursday, Andrew and Martin had a pallet collection run for the Steam Loco Department, this should be the last of these jaunts for a good while. After dropping the load at Toddington they headed up to Broadway to call in at the station cafe for a break, the cafe is open on Thursdays even though there aren't any trains running. 

Report from Andrew... 

Culvert 2A down side concrete headwall 

Broadway footbridge across the end of Culvert 2A 

The next adventure was to head north under Springfield Lane and up to the culvert at Smallbrook Farm. This is the old trackbed that doesn't belong to the GWSR, but the station drains run along to empty at the culvert, hence the need to check it each year. 

Smallbrook Farm Culvert down side 

Smallbrook Farm Culvert up side 
Nasty crack in the headwall 

Good flow in the cess drain north of the A44 

A couple of the chambers need to be sorted out 
dropped ring and lids here 

Lids need retrieving in this one 

Martin in the search for a chamber 

Something (or somebody) is creeping in under the
palisade gate at the end of track at Broadway 

While out and about candidates for the milepost replacement programme get noted and added to the list...

Milepost 4¾ in need of attention 

The numerals used on the extension markers
aren't GWR pattern, they don't look right - Milepost 5¼ 

Sadly the Friday gang were overtaken by other events, not railway related, and were unable to attend. The saga of Bridge 29 down side coping recreation will have to wait for another week.