Yumbe District Engineers Invent Tool for Opening Up Clogged Boreholes
The water department of Yumbe district has invented and fabricated a hand held tool for silt removal from boreholes. In Yumbe, upto 85% of the population depends on boreholes for water but only 75-89% of established boreholes are functional according to a district brief introducing the new invention. Silting is a major contributor to the dysfunction of boreholes but unclogging one using modern technology (a compressor) costs about UGX 7m. The engineers who created this new tool explain in the briefing paper that is cuts the cost of this process to UGX 2m.
The tool is made out of steel round hollow section 100mm in diameter and 350mm height. The bottom of the tool is sealed and provided with propeller like cutting edge structures. To use it, the tool is connected to pipes and lowered into the well until it touches the silt. The end of the last connected pipe is then connected to a cross bar and rotated. This makes the tool to cut into the silt and as it digs deeper in, the cut silt is pushed upwards. When the tool is filled up with the silt, it is removed and the silt emptied. This process is repeated several times until when the tool has reached the original drill depth of the well.
In its present iteration, the tool is quite labour intensive. It may take 2-3 days to completely clean out a clogged boreholes. Nonetheless, contractors have shown some preference for it over the more expensive modern technology, according to the briefing paper. It has so far been used to clean out used 10 boreholes in the district.