Monday, 5 March 2012

Water and Walls

I went down to the reserve this morning but after an hour and half of being pumelled by an icy cold NW gale I gave up and did what most of the birds seemed to have done, and cleared off. Boy, if ever a day was designed to be the opposite of last week's glorious weather, today was. Clouds raced across the sky in a gale that was touching 50mph at times and it was alternatively dark or bright depending on the cloud cover. Over the seawall, the high tide in The Swale was higher than it should of been as the tide was funnelled in by the gale and white-capped waves raced down the middle channel.
But it was not all a waste of time - part of the reserve has water again, no, yesterday's rain was not of the monsoon variety - the borehole is working again! Regular visitors along the seawall of the reserve might of noticed a small shed at the western end of the grazing marsh, this housed a generator that sits over a borehole sunk into the underground aquifer. Until the generator broke down a few years ago we pumped water from this borehole into the shallow rills at that end of the reserve in the Spring to maintain the conditions required by the breeding Lapwings, etc. The reserve management has now replaced the defunct generator with a mobile one and water is once again flowing again, as you can see below as the first rill fills up.
The supply of this water will be limited and to only that end of the reserve but its going to be a major benefit to the reserve and the Lapwings there.

And on an entirely different subject, I came across the two photos below in one of my albums today. They are from my Kent River Authority (KRA) days and were taken in September 1971 on the seawall between Sheerness and Minster. A few years after the photos were taken the seawall was completely re-built and is now higher and much wider and is protected on its seaward side by huge rocks barged in from Scandinavia.
However in those days it was an old and narrow and basically just a clay seawall covered in small rocks and cemented. Unfortunately, due to the force of the tide on that northern side of Sheppey, the cement and rocks would regularly need replacing as they got washed away. Prior to the building of the new seawall the KRA carried out inspections of the seawall and were horrified to find out that over the years large areas of the original clay seawall had been eroded away and in places it was literally a concrete shell over large holes. So, before the new seawall could be built, it was deemed necessary for us to spend a couple of months there pumping in concrete at high pressure to replace the missing clay. So we first went the length of the seawall drilling holes up and down it and pushing a wooden peg into each hole as a bung. One of us, normally me as in the photo below, would then go along and at regular intervals pump concrete into one of the holes until it begun to force the bungs out in that immediate area.
Like everything on the KRA in those days, everything we used was archaic. The only way we could seal the hole around the pump spout as the cement went in was to use a rubber sorbo ball on the end. We would have to hollow out a hole through the ball and then push it over and up the spout so that it became a seal round the hole in the wall. The pressure behind the concrete going in was so graet that you only had to lean the pump over slightly and break the seal and you got covered in the stuff, as my overalls below show.

To complete our archaic equipment there was no super, modern ready-mix lorries supplying the concrete, we did it ourselves. Each day two of our lorries would back up to each other on the main road and on one, two men would shovel sand and cement into a large mixer, which would then be fed into a hopper on the other lorry and then pumped over the seawall to me on the other side.
It was quite an easy operation for both myself and the pump operator, as you can see by his bored look on the lorry, but the two guys preparing the concrete shoveled away like billy-o all day long feeding the mixer.

No comments:

Post a Comment