Drainage team is still active!

Yes the drainage team is still very much alive and active, despite lack of blog activity!

Since the last posting on this blog, the team has undergone a few changes. Stu, who was the Head of Department prior to the merger to form the Estates Management Department, has moved to C&W Carriage Cleaning (and helping restore the Thames & Severn Canal). Dieh and Michael have both unfortunately retired on medical grounds, hopefully temporarily. New recruit Polly has joined the team, as a professional brick layer he has substantially increased the rate of construction. The other five team members are Roger, Nigel, Dave, Martin and Andrew.

Here is the first blog post to catch up with the activities since the second week of May.

Tuesday 11 May

Main job was to start filling in the new toe drain ditch at Culvert 27B up side at Gretton. We spoke with the owner of the adjoining land and agreed the path for the barrow run. We put planks down near the gate to minimise damage from barrow wheels. The land owner thought the wet area near his fence was slowly drying out - it was hard to tell as there had just been quite a heavy shower and thus rainwater puddles. Water was flowing well down the new ditch.

Water flowing into the culvert 27B exit ditch from both the new toe drain pipes.

We installed bricks and slabs at the point where the side ditches are collecting water from the embankment and the garden. Most flow is from the garden - quite possibly this is a groundwater spring which previously had flowed into the blocked green plastic land drain. We collected two loads of pea gravel (about 1 and quarter dumpy bags) and some bigger chippings from Gotherington yard, then filled the ditch above the new pipes with this. Placed the bigger chippings and assorted half bricks and other hardcore at the ends of the pipe - and reused some of the old clay pipes. Then roughly infilled with the excavated earth/clay. 

Pea gravel covering the plastic pipes in the new ditch, area under gate where on pipe connects to land drain on neighbours property

On first visit to Gotherington yard we spotted two sheep and five lambs on the track. Reported to Winchcombe signalbox, however the first down train has just departed there. Cajoled the sheep over to the up side and they scampered back to the field through a gap in the fence by culvert 33A.We checked no other animals present before train arrived, then make temporary repair to the fence using a length of green rope we had on our truck.

Very temporary repair to a hole in the lineside fence at Gotherington, at least it keeps the sheep out.

After passing of last up train we inspected the area of the embankment at Far Stanley where movement had been detected. This area approximately coincides with the highest point of the surrounding land on both sides. The land on the down side has pronounced medieval ridge and furrow farming patterns which are almost at right angles to the embankment. On the down side there is a toe drain running for the whole of this length, this is post BR construction. On the up side there is no drain, and the area is historically known to be damp.

 

Tuesday 18 May

Four team members in today. Two first went to Toddington to investigate reports of soil being washed down the cutting side under the down side of the Stow Road bridge. Looks like this has been ongoing for a while. The source is the road above, which may be worse now it has been resurfaced. The runoff goes under the side arch of the bridge where there is no vegetation and thus is carving gullies in the soft soil. We cleared the muck of the top of the S&T cable concrete ducts. The cess is damp under the bridge. We discovered a Salt Glazed pipe further back (low mileage) on the cutting side, about half way up and directly in line with the S&T junction cabinets. This maybe a land drain from the adjoining field.  Further investigations and formulating a plan to get this run off into the down side cess drain are required. Looks like not a straight forward job.

Stow Road Toddington, down side arch. Water run off from the road above is gradually eroding the soft soil here.

Main event was the start of construction of the new headwalls at Working Lane. There was too much water flowing in the 25B outlet ditch to start that one. Will need to wait for drier conditions or build a more substantial temporary dam and bypass.

 

Working Lane up side where culvert 25B exit channel is now piped to join 25A. We will construct a new headwall here, but too much water flowing today to make a start.

 For culvert 25A, which is the brick channel under the bridge, we laid the first few courses, using recycled concrete blocks from Royal Oak (down side) and blue imperial bricks. Not the easiest of sites to work on - particularly with having to cut many of the blocks to fit.

Picture by Roger. First new bricks laid for over 14 months by the team. This is the start of the new headwall where culvert 25A is now piped beside the lane to the junction with 25B outlet.

 

 

End of day one on the 25A junction inlet headwall construction.

 Tuesday 25 May

Seven team members attending - making this the largest attendance since start of the COVID-19 pandemic. Two of us met with the Bridges Engineer and Structures Chief to agree the logistics of the visual inspections to be undertaken by the drainage team this year. Basically this covers the structures classified as cross drains and culverts apart from those that will be subject to external detailed inspection.

Then Andrew joined Estates Management HoD Mike visiting Hunting Butts where the fencing contractors are now working on the down side crest. The crest drain ditch is coping reasonably well with the run off from the field. The contractors reported that towards the tunnel the ditch had almost emptied overnight after rain had stopped. Towards the station the ditch contained more water, agreed that the contractors would use their digger to deepen this slightly and remove tree roots. 

Down side crest ditch at Hunting Butts, new fence in background. This was flowing slowly!

Back at Working Lane, the other team members continued work on culvert 25A headwall at Working Lane and started repairs to the high mileage up side wing wall on bridge 25. It was still impossible to start work on the new headwall of the 25B to 25A junction, as too much water flowing there. Not surprising after almost two weeks of rain every day.  First load of infill collected from Manor Lane Gotherington and placed behind the new brick/block courses.

 

25A junction inlet headwall, brick and block courses now well above the water level. Working here you hear trains but don't see them.

The wing wall repairs involved removing the lower two rotten wing wall fence posts. Once the coping stones are back in, we can fit new posts and horizontals. 

Roger attends to Working Lane bridge up side high mileage wing wall.

 

 

Our wildlife find today - slow worms. One scuttled off quickly, but the other stayed for a photo!