Sunday 8 August 2010

Hare Hill 8 August 2010

Four of our volunteers turned out the Hare hill, and spent the day working with the warden and two local volunteers working to maintain the field drains under the park land surrounding the garden. This land is naturally quite wet and boggy, and relies on a large network of old land drains to remove the excess water. We have spent some time in the past revitalising this network.

In the first photography you can see the line of the drain where the land has sunk slightly, along with the T bar - useful for finding drains less obvious than this one, and a "stag head" oak - which has suffered from waterlogging and died back as a result

This time we revisited some sections that we had worked on previously as it is suspected that the network will require some routine maintenance. As a result we knew exactly where to look for the drain, and how it would be constructed.

The basic proceudure is to dig down to the main junctions in the network, open them up, and use drain rods to "explore" by feel up and downstream. Then to dig down at other points either where the drain rods run out or where they get stuck. Often these points are caused by slipped bricks (as in the photo above) or a broken cap stone. Once the bricks have been reset and the rods can be easily worked from hole to hole, a disk is put onto the end and dragged through to pull out any remaining mud. Finally the cap stones are reset before the drain is reburried.

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