May 2010 – drainage

After the last couple of years of wet summers & winters the long dry spell was a welcome change. It also provided the ideal opportunity to drain the main field. The lower half of the field (next to the stream) has been waterlogged for long periods and the old clay drainage pipes  (visible from the banks of the stream) have become blocked or collapsed.

A mini digger was hired, 5 x 50m of 150mm perforated drainage pipes were purchased. A catchment ditch was cut across the top of the field, breaking through the old clay pipes (releasing large amounts of water!) this was then angled across the field to the stream. The soil/clay that was dug out was spread thinly over the field, trying to fill in the dips in the field that collect water. The pipe was laid in the ditch and infilled with 40mm clean gravel and the final 18″ filled with top soil. Sounds simple but with over 130 tonnes of gravel and top soil needed was a big job. This was made significantly easier by the hire of a bobcat, ideal for scooping up gravel and top soil, an amazing machine (not the greatest off roader but coped with the dry field, although did get it stuck once!)

Amazing amount of water once you start digging!

Once the gravel and the top soil was filled in, the mini digger was used to do the mucky job of spreading the clay/topsoil that had been dug out of the ditches. This didn’t take long but in the process spread an enormous amount of small stones contained in the clay over the field!! The next few weekends were spent picking up stones! Eventually the field was ready to reseed, so was harrowed hard (bring more stones to the surface – argh!!!) over-seeded and  rolled. All that was left to do was wait for some rain, watch the grass seed grow and hope the drainage pipes work!

A good application of  ‘muck’ over the field in the new year, will help the clay to break down (as well as a hard frost!) and allow the roots of the new grass to penetrate more easily. Ideally next year will get a contractor in to ‘mole plough’ perpendicular to the drainage pipes to achieve a well drain fertile field. A soil test to determine the acidity (hopefully reduced now the soil isn’t waterlogged) a top dressing of lime – perfect field!!

Last bit of gravel!