Saturday 1 August 2015

Waterworks 1

With the hot sun and strong breezes rapidly drying the soil after the winter rains it was possible to assess more accurately the problem the diggers had encountered when trying to construct the drive up the plot from the house.

At first it was thought that the sheer volume of water overflowing from the storage tank and moving down the site was causing the diggers to sink up to their axles into the drive at the point where this flow and the drive intersected. However, by ensuring the overflow was directed away across the site and the drying weather it became apparent that there was, as I had long suspected, a slower and deeper spring outlet following the same line down the plot.

Whilst the rainfall last winter was exceptionally high I decided that a small catchment tank with an overflow directed away from the drive would be a sensible precaution.

The digger that was on site therefore dug out a hole which was then lined with a couple of the standard cess pit concrete rings which were themselves lined with polythene  to form a tank with a gap being left on one side to allow the water to enter the tank.

It was then capped off with the standard capping and an over flow made so that any excess of water would join the around the house drainage system and be used to water an area lower down the plot.

Given the design of the house, earth sheltered on all but the south facing window wall, the only practical option for the drainage, and sewer runs was along the front of the house. The digger, therefore, dug a suitable trench and the necessary pipework was installed with access points at all joins in order to facilitate easy resolution of any problems.

Some of the rocks previously put on one side for walling purposes were built into a rocky retaining wall to support the soil at the side of the drive adjacent to the newly installed water run off tank and to provide a natural way for the excess water to make its way into this mini holding tank before seeping away or being run off, via the overflow, down the site.

Starting to dig the hole for the catchment tank.

Unloading the concrete rings.

Moving the first ring into place.

First ring in place.

After adding second ring polythene was used to line the tank leaving the up slope facing side exposed to allow the water to seep through and collect in the tank and then it was topped off with a concrete lid.

Digging the trench for the sewer and waste water runs.

Laying the waste water run to carry the around house drainage water and the overflow from the newly installed catchment tank.

Laying the sewer run.

Building a retaining wall at the side of the drive, using rocks previously dug out of the excavation, to support the soil and provide an easy run off into the newly installed tank.