Borehole drilling

drilling_1TASTE are the proud owners of a PAT401 rig. With this rig we are able to drill to 200 metres, far deeper than anything we are likely to encounter in Plateau State. However, further afield, we are likely to have to drill close to our maximum capacity before encountering decent volumes of water.

Having conducted a geological survey to ascertain the most suitable point for a borehole, our drilling team get started. As they progress, the borehole is lined with casings – the big blue pipes you see in the picture. As work continues, the team are able to determine the geological structure they are drilling by examining the cuttings (the material that is flushed to the surface by the drilling process). Having reached the depth recommended by the geologist, the team use compressed air to flush the hole and then check that it fills quickly enough with water. If they are happy, they use a clay powder to stabilise the hole (by adding it to water and pouring it around the blue pipes as a sort of glue) and then hand over to our pump technicians.

Jonathan and Yohanna are our pump technicians and they work with local masons to cast a platform for the hand pump. However, before they do that, they need to insert lengths of steel pipe inside the blue casings.

The steel pipe acts like a giant straw with the hand pump acting like a big suck! The handpump draws the water up the pipes and out to the waiting public.