Montgomery Canal Restoration Work Party Report - July 2010
July 3 & 4
As with the June work party, July brought a hot Saturday, followed by a much milder Sunday. In the time between the June and July work parties, a small but extra-dedicated group of volunteers helped deliver several lorry loads of concrete. This was used to create the new base under Pryces Bridge, and to fill the block work retaining walls adjacent to Redwith Bridge. During the work party, work continued in 3 main areas.
At Pryces Bridge on the shaping of the channel. The French drain which had been put in the previous month proved most effective, quickly lowering the water level and allowing people and machinery to work without danger of sinking in to the mud! The pump was kept running for most of the weekend, as the flow of ground water into the area was relentless. Although the channel shaping at this end has got off to a slow start, this has mostly been due to the the need to perfect the method using the digger, given the constraint of working within the channel. The short section of channel that was shaped at the Redwith Bridge end was done fairly quickly, but in comparison, the Pryces Bridge end requires far deeper excavation, less stable ground, and a far greater area on the sloping sections. The aim is to perfect the shaping technique now, to ensure that the rest can be shaped at a reasonable speed, and be shaped correctly the first time. By the end of the weekend a 10 metre section had been fully shaped, both sloped sides and base, with most work done by the digger, and only minor fiddly bits (such as around the piling) done by hand. A good result.
The wall building team continued their work on rebuilding the section that had been removed due to frost damage and concrete movement. The removal of the damaged sections was completed the previous month, so the team was able to work at full speed to reconstruct the wall. A new method of placing the formers used to guide the builders has had to be be implemented but does not seem to slow the process down. Once this section of wall has been rebuilt, the wall building team will move to the retaining wall at Redwith Bridge, to complete the tops of the newly-filled sections. To help plan ahead for this, unused stone left over from previous sections of wall was moved up to near the retaining wall. While building the stone top of the retaining wall should be simpler than the batter wall as they are straight and vertical, it will be more physically demanding as the stone will need to be lifted to head height.
At the centre of the length, adjacent to the vertical wall, work started on relocating the drainage ditch and marking out the offside of the canal. For some unknown reason over the years the offside along this section has disappeared. This will need to be built up to a suitable height using the spoil that will be removed by the channel shaping work.
|Fine adjustments||The channel takes shape|
|Testing the new concrete bridge invert||Nearly there..|
|Last Time||Next Month|