Drilling Costs and Quality

Accurate information on drilling and prices or costs in sub-Saharan Africa is not easy to access.  National, or programme averages hide more than they reveal.  Simple league tables of national drilling costs as an incentive to drive down expenditure on boreholes are not very helpful .  The table below gives some examples of costs and prices. 

The Difference between Borehole 'Cost' and 'Price'

‘Price’ refers to the amount paid by the Government or project for the successfully completed borehole.

‘Cost’ is the ammount borne by the contractor, consultant(s) and in some cases Government. 

Borehole Costs and Quality

The cost of a borehole comprises a number of components, and sub-components as given below:

1. The basic costs to the driller comprise costs of

a.   Mobilisation – all costs involved in transporting equipment to site and back to base.

b.   Drilling – allows for the per-hour (converted to per-meter) costs of equipment depreciation, labour consumption of fuel, lubricants and drill fluids and replacement of drilling tools.  Affected by depth; diameter; drilling and standby time. 

c.   Casing – includes the supply and installation of plain casing and screen, gravel pack, sanitary seal and well-head construction.  As an example, PVC casing is used in Burkina Faso whereas stainless steel, at four to ten times the cost is used in Senegal (ANTEA, 2007).

d.   Well development refers to the cleaning of the borehole after construction and test pumping is the post-construction assessment of borehole and aquifer performance.

The time taken to undertake these activities affects the basic drilling costs. 

2.  Additional costs to the driller include VAT, tax, overheads and kickbacks (when this is the common practice).  Some of which these are hidden within the Bill of Quantities (BoQ).  An astute driller will assess the requirements for a particular tender, consider the risks involved and load particular items in the BoQ accordingly.

3.  Pump costs vary considerably and are in some cases included in quoted borehole prices. 

4.  Siting costs can be borne by the Government /programme, driller or consultant.  Where consultants undertake this, the costs are clear and visible.  In cases where supervision is undertaken by programme or Government staff, the costs are often concealed within programme expenditure.  This may also be the case for costs of supervision and social infrastructure.

5.  Supervision costs are generally borne by the Government or programme, or consultants (as above). 

6.  Costs of Social Infrastructure, ie mobilising and training communities and forming management groups.  These costs are also sometimes hidden within programme expenditure.

7.  Construction quality refers to the degree to which the borehole is straight; the quality of well development and gravel packing; the casing/screen quality including its installation; the permeable backfill material and placement; the quality of the sanitary seal and headworks. From the user perspective, turbid water, low flow rates, seasonal functionality all represent compromises on quality of service.

References

Adekile, D.  2007. The Drilling Environement and Establishing a Drillers Association in Nigeria. Consultancy report RWSN/WSP

Mthunzi, M.  2004. Monitoring of Partially Cased Boreholes.  Research Report of Concern Universal.  

MWE.  2007.  Uganda Water and Sanitation Sector Performance Report 2007.  Ministry of Water and Environment, Government of Uganda.