Siting for Boreholes at Mulenje

This past week and a half we took 3 trips into the Mulenje Community doing a survey of the areas we would like to do boreholes.  The survey process is called "Siting" and it involves looking for a likely spot and then setting up a resistivity instrument and taking reading of the resistance to electrical currents in the earth.  A probe is driven into the ground each side of the instrument at about 7 meters from the instrument.  The probe is connected to a wire that comes from the instrument and a charge is sent into the earth through the probe.  It returns thru the other probe and the reading is recorded.  The probes are then moved a few meters further away and another reading is recorded.  This happens repeatedly until the probes are each 100 meters from the instrument.  This data is then entered into a computer program and it gives a graph that shows how deep the possible water is in the earth.  Water conducts electricity so there is little resistance to the electrical current when it passes thru water as compared to the resistance when the current passes thru earth or rock. 

         Here is the resistivity instrument.  You can see the wires leading away from the instrument.

 

Here is Darius Banda recording the readings.  He works for the Department of Water Affairs and has been taking these readings for 20 years.  In the background, directly above the instrument, you can see the probe and the spool of wire (yellow object) that is connected to the instrument.

 

 

When we were last in Mulenje we had taken several readings with our GPS instrument so that we could locate the community on Google Earth.  We plotted the points on Google Earth and then zoomed in over the community to see where people were living.  There were several locations in the 28 square kilometers where the people were more concentrated.  On Google Earth we located those areas where we thought a borehole would serve a maximum number of people and then we took the coordinate readings of those areas so we could drive close to them in the bush.  When we went back to Mulenje we drove to the areas with the help of a native guide and then relied on Darius to pick the places to take the readings.  At each area we took two readings so that we could pick the best placement for a borehole. 

 

Our first stop was Mulenje Community School.  They had made improvements in the school by paining and install glass in the windows.  This gave us hope that they would be sure to take care of the borehole since they are improving the school.  You might remember a previous blog that had a picture of this room and the wall was the blackboard.

 

 

The siting here was done at an ant hill.  The ants are supposed to be good at detecting the underground water.  This is a small ant hill compared to many.  The stake in the foreground is where the siting was done.  We record the locations with our GPS device.

 

 

On our next trip we visited two locations on the east side of the community.  We forgot our maps and coordinate information so we had to rely on our study of the area on Google Earth and The Spirit to give us direction.  When we attempted to go to our first desired area we found that there was already a borehole constructed there that we had not been told about, so we drove in another direction to find others who were not being served with clean water. 

 

Here is the existing borehole.  It is constructed very nicely.

 

 

The second location was to the north and located near to where the assistant headman lives.  He showed us where they are currently getting some of their water.

 

 

While there we also took a look into his year's supply stored in this enclosure.

 

 

This is their staple food, white maize.  They mill this and then make the nshima which they eat almost every meal.  If they don't eat it then they feel like they haven't eaten.

 

 

On our third trip we went to an area in the middle of the community.  We were impressed with the neatness of their buildings.  Check out the paint job.

 

 

We did two sitings here, and while Sister Bodily was waiting some young boys convinced her to try some wild fruit.   Elder Bodily did not need to try it after Sister Bodily described the taste.

 

 

We then headed to the Southwest corner of the community.  We knew where we wanted to end up but our guide kept on taking us to where he wanted to go.  With out maps and GPS device we finally convinced him that we knew where we wanted to be.   After circling around where we wanted to be on roads and trails in the bush, we were successful in arriving at our desired location.

 

Here we find ourselves at another ant hill.  However, Darius thought our second siting in this area was better even though it was in some thick brush.

 

 

 

Some boys had skipped school that day, so they along with some men were watching what we were doing.  They are always interested when you are considering bringing them some clean water.  This 12 year old boy was always close so we had him help pick up the equipment when we were finished.  He seemed pleased to be included.

 

 

Now we wait for the results of the survey.