Factors to consider when selecting a borehole pump
Choosing the wrong borehole pump wastes money and shortens equipment life. Here are the key factors — yield, depth, water quality, power, and daily demand — to get pump selection right.
Your borehole is only as useful as the pump running it. Submersible pump selection is a technical decision that must match your borehole's tested yield, total dynamic head, water quality, power source, and daily consumption pattern. Get it wrong and you face low pressure, high bills, frequent repairs, or a pump that burns out within months.
This guide explains the factors Powerwell evaluates on every equipping project — so you know what questions to ask before buying a pump.
1. Sustainable yield from test pumping
Never select a pump before test pumping is complete. The pump's duty point must fall within the borehole's sustainable yield — not its maximum short-term output. Pumping beyond sustainable capacity causes excessive drawdown, sand ingress, and aquifer stress.
Your test pumping report is the starting document for all equipping decisions. If a supplier quotes a pump without seeing this data, treat that as a red flag.
2. Total dynamic head (TDH)
TDH is the total equivalent height the pump must overcome — including static lift, drawdown during pumping, friction losses in the rising main, and delivery pressure at the tank or tap.
Deeper installations and long horizontal pipe runs require higher-head pumps. TDH is calculated from site measurements, not estimated from borehole depth alone.
3. Daily water demand
Domestic households, dairy farms, greenhouses, and commercial buildings have very different peak and average demand. The pump must satisfy peak hourly demand while the borehole yield supports daily volume over the pumping window.
Storage tanks buffer demand: a pump filling a tank over several hours can serve short peak periods. Irrigation systems may need simultaneous flow at multiple outlets — requiring higher flow rate and careful pipe sizing.
4. Water quality
Saline, sandy, or iron-rich water requires pumps and materials suited to those conditions. Corrosive water accelerates wear on standard components. Abrasive sand damages impellers and seals.
Water quality laboratory results, combined with geological knowledge of your area, inform material selection and whether pre-filtration or treatment is needed before distribution.
5. Power source: grid, solar, hybrid, or generator
- Grid electric: widest pump selection; consider tariff, phase availability, and backup needs
- Solar: pump and controller must be matched to array output; often best with tank storage
- Hybrid: solar primary with grid backup for extended cloudy periods or night pumping
- Generator: common on farms; size generator and pump start current carefully
Solar pump sizing is directly linked to test pumping yield and daily volume — not panel count alone. See our article on borehole solarization for more on solar-specific selection.
6. Pump type and construction
Submersible borehole pumps differ in impeller design (centrifugal, progressive cavity), material grade ( stainless vs bronze vs plastic components), motor rating, and cable specification.
Key specifications your contractor should document:
- Flow rate (m³/h or L/min) at duty point
- Head (metres)
- Motor kW and voltage
- Cable size and length
- Control panel protection (dry-run, overcurrent, surge)
7. Installation depth and clearance
The pump is typically set several metres above the borehole bottom to avoid sand ingestion, with minimum submergence maintained above the dynamic water level during pumping. Incorrect setting depth is a common cause of early failure.
Professional installation includes secure headworks, compliant cable joining, vibration-free drop pipe, and tested electrical earth.
8. Future maintenance and spare parts
Choose pumps with available spare parts and local service support. Obscure imports may be cheap upfront but expensive when a seal kit takes weeks to arrive during dry season.
Powerwell specifies pumps with proven field performance in Kenyan conditions and provides ongoing maintenance support.
Get expert pump selection from Powerwell
Pump selection is included in every Powerwell equipping package, driven by test pumping data and your stated water use. We deliver correctly sized, installed, and commissioned systems — domestic, agricultural, solar, and commercial.
Review our borehole services, explore the full drilling and equipping process, or request a quote for professional pump selection on your site.