Borehole depth in Kenya varies significantly by geology and location. In Nairobi and the central highlands, productive aquifers in fractured basement rock are typically encountered between 40 and 120 metres depth. Along the coast, sedimentary aquifers can be struck at 20 to 60 metres. In the Rift Valley volcanic terrain, depths range from 30 to 150+ metres. In ASAL northern Kenya, depths of 100 to 250 metres or more are common. These are typical ranges — the actual productive depth at a specific site depends on local geology, and a hydrogeological siting survey reviews all available data to estimate the expected depth range and yield before drilling begins. This is the reason a siting survey is so important: it avoids the expensive mistake of stopping drilling too shallow, or drilling unnecessarily deep.

Yes — every borehole in Kenya used for water abstraction requires a valid Water Resource Management Authority (WRMA) abstraction licence under the Water Act 2016, regardless of the scale of abstraction or the purpose. Operating a borehole without a WRMA licence is an offence. Maji Hill prepares and submits the complete WRMA application as part of our standard borehole service — the application requires a hydrogeological report, borehole completion report, yield test data, GPS coordinates, and the intended use and abstraction volume. We manage the application through to licence issuance. For clients who already have an unlicensed borehole, we prepare and submit a retroactive licence application to regularise the position with WRMA before an inspection identifies the non-compliance.

The correct pump depends on the borehole’s confirmed safe yield from the yield test, the static and dynamic water levels, the required flow rate at the surface, the borehole diameter and casing size, and the power source available. The most common pump for Kenyan boreholes is a submersible electric pump installed below the dynamic water level. Pump selection must be carried out after the yield test — installing a pump rated higher than the aquifer’s sustainable yield will pump the borehole dry, damaging both the pump and potentially the aquifer. For off-grid sites, solar submersible pumps are an increasingly cost-effective option. Community water points often use hand pumps for simplicity and maintenance ease. Maji Hill selects, sizes, and installs the correctly matched pump for every borehole we drill.

Borehole water quality in Kenya is variable. Some boreholes produce excellent potable water that needs only disinfection. Others have elevated fluoride (common in Rift Valley, ASAL areas), iron and manganese (common in basement rock areas), nitrate (near agricultural land), or microbial contamination (near surface water or sanitation facilities). You cannot tell from appearance or taste alone whether borehole water is safe. Maji Hill carries out comprehensive water quality sampling and accredited laboratory analysis against Kenya Bureau of Standards drinking water standards on every borehole we drill. Where parameters exceed standards, we design and install the appropriate treatment system — UV disinfection, iron removal filter, fluoride reduction unit, or reverse osmosis — as part of the borehole completion package. Drinking untested borehole water is a health risk that is easily and affordably eliminated by proper testing.

The complete borehole project timeline in Kenya from commissioning to a licensed, pump-equipped, water-tested borehole is typically 8 to 14 weeks. The siting survey takes 3 to 5 days. Drilling a 100 to 150 metre borehole in typical Kenyan geology takes 3 to 7 days. Casing, development, and yield testing add 3 to 5 days. Pump installation takes 1 to 2 days. Water quality laboratory results take 10 to 15 working days from sample submission. The WRMA licence application currently takes 4 to 8 weeks for processing after submission — this is the main timeline driver and is outside Maji Hill’s control. We submit the WRMA application as soon as the completion data is available to minimise the waiting period before the licence is issued.

Some failed or low-yield boreholes can be rehabilitated — but the feasibility depends on why the borehole is underperforming. If the issue is borehole encrustation (mineral scale deposited on the casing and screen reducing flow), rehabilitation by acid treatment or mechanical brushing and jetting can restore yield. If the screen is blocked by fine material that was not properly developed out during construction, airlifting and surge development can improve yield. If the pump is incorrectly sized or installed at the wrong depth, replacing or repositioning it may solve the problem. If the aquifer itself is of limited yield at that specific location — a poor siting decision at the outset — rehabilitation cannot generate water that is not there. Maji Hill assesses failed boreholes, identifies the cause, and recommends rehabilitation where it is technically viable, or a new well at a better-sited location where it is not.