Boreholes are emerging as one of the ways of supplementing water resources for household, irrigation, and other agricultural uses in Kenya. Following is a review of the process of drilling a borehole in Kenya
The process of sinking/drilling a borehole starts with sufficient justifications for the same. This justification is important considering the costs of drilling, which can easily run into millions. In Kenya, some of the common justifications for sinking a borehole include to supply water to residential buildings and irrigation. The former is mostly done privately while the latter is done by government agencies in charge of agriculture, water and irrigation. With sufficient justification, one can then proceed to sink the borehole or to hire an expert to guide the process. Hiring an expert is much better option considering the technical nature of borehole installations.
2. Hydrologist report
The next step of the process is finding a qualified hydrologist to prepare a report about the selected site for drilling. The report contains, among others, the detailed background of the project site, including the climate, water supply and demand; the geology of the area; the hydrogeology of the site; and geophysical investigations. The report will also contain a list of other water resources in the area and information on whether sinking the borehole in the location is sustainable. If the hydrologist confirms that indeed there is sufficient water to be abstracted in the site, the project proceeds to the next phase.
3. Borehole costing
The next stage of the process is to cost the drilling. Here, qualified technicians from companies that offer borehole drilling services should be engaged. Usually, the companies will prepare a quotation for sinking the borehole for free. In some cases, the cost is incorporated into the overall project costs. A borehole bill of quantities will be the primary output at this stage. The bill of quantities will inform the investor whether to proceed with the drilling or to abandon the project. If he/she chooses to sink the borehole, the project progresses to the next step.
4. WARMA and Environmental Impact Assessment
In the next step, the investor documents the project and shares the same with Water Resources Management Authority (WARMA). The authority will review the proposal, paying particular attention to the hydrologists reports. If satisfied, the authority will issue a permit and allow the investor to drill the borehole. But, before he/she proceeds with the drilling, he/she will have to submit the full proposal with the accompanying permits to National Environmental Management Authority (NEMA). NEMA will review the environmental friendliness of the project and decide whether or not it should proceed. If they agree, the project proceeds to the next stage.
5. Drilling/sinking, pumping and water tests
With the WARMA and NEMA permits in place, the investor can proceed to sink the borehole. Here, contracting the services of qualified professionals is highly advised, largely because the drilling process is a highly technical endeavor requiring specialized skill set. Typically, contracted companies will sink the borehole and also conduct pumping and water tests. Pumping tests are required to determine the yield of the borehole, which informs its uses, while water tests are needed to gauge the usability of the abstracted water for a range of purposes including domestic water consumption and irrigation. Once the borehole is sunk and all the required tests conducted, the next step is equipping the borehole.
6. Equipping boreholes
Equipping boreholes is done to bring the installations into a functional state. It entails finding a suitable way of abstracting and pumping the water to the point of use. The investor can do this by himself or his agents. Alternatively, he/she could engage the services of water and pump companies. The companies will ask for the borehole test reports and other site information from the client, which they will use to determine the cost of equipping the borehole. Typically, the companies will prepare a quotation for equipping and the client will either buy the equipment and do the equipping or engage the company do it for him/her. In government projects, equipping works are tendered.