A hydrogeological survey in Kenya helps property owners, farms, institutions and developers assess groundwater conditions before committing to borehole drilling. Hamiki Engineering’s survey scope brings together site information, field reconnaissance and geophysical interpretation to identify a defensible drilling target and explain remaining uncertainties.
What is a hydrogeological survey?
A hydrogeological survey investigates conditions that influence groundwater occurrence and movement. For a proposed borehole, the objective is to use available evidence to assess suitable locations and guide planning. Depending on the agreed scope, work may include desk review, field reconnaissance, geophysical investigation, interpretation and a report identifying a recommended drilling point.
A survey reduces uncertainty; it does not remove it. Groundwater conditions can vary over short distances, and geophysical indications are interpreted alongside geological context and field observations. A survey should not be treated as a guarantee of a particular depth, yield or water quality.
Hydrogeological investigation is one part of Hamiki’s broader borehole drilling and water engineering services. Findings can inform drilling, while test pumping after construction helps assess the completed borehole’s actual performance.
Why carry out a survey before drilling?
- Support site selection: compare available evidence and identify a recommended target.
- Improve planning: give the project team information to consider access, drilling approach and anticipated construction needs.
- Record decisions: document observations, interpretation and recommendations.
- Manage uncertainty: explain what the evidence suggests and what cannot be confirmed until drilling and testing.
- Coordinate the water system: connect groundwater investigation to intended use, pumping, storage and distribution.
What does the survey process involve?
1. Understand the site and intended use
Collect the project location, proposed use, access constraints and existing records. Water demand differs between a household, livestock unit, irrigation scheme and institution. This context helps frame the investigation and subsequent design decisions.
2. Review available information
Existing geological information, nearby borehole records where available, topography and site observations may inform the investigation. Nearby borehole performance provides context, but it does not prove that another point will have the same depth or yield.
3. Conduct field reconnaissance
Field observations help the survey team understand access, surface conditions, potential constraints and locations available for investigation. Property boundaries, buildings, utilities, drainage and rig access may affect where a borehole can reasonably be placed.
4. Carry out geophysical investigation where included
Geophysical methods, such as electrical resistivity work, measure physical responses that help interpret subsurface conditions. Survey layout, measurements and interpretation should be appropriate to the local setting. The result is an evidence-based interpretation, not a direct view of groundwater underground.
5. Interpret and recommend
Observations and measurements are considered together to identify a recommended drilling target and relevant limitations. The report should explain what was investigated, what was interpreted and what needs confirmation during drilling.
6. Use findings in project planning
The survey can inform the drilling scope and help prepare for next steps. Final construction details depend on formations encountered during drilling, while pump selection should follow borehole completion and performance information.
What should a survey report explain?
| Report element | Purpose |
|---|---|
| Site and project details | Identifies location and intended water use. |
| Method and field observations | Explains the investigation approach and observations. |
| Interpretation | Describes how the evidence was interpreted. |
| Recommended drilling target | Identifies the recommended location within the agreed scope. |
| Limitations and uncertainty | Clarifies what can and cannot be established before drilling. |
| Planning recommendations | Connects findings to drilling and subsequent testing. |
Hydrogeological survey versus test pumping
These services answer different questions. A hydrogeological survey is used before drilling to investigate the site and support a drilling target. Test pumping is performed on a completed borehole to observe discharge and water-level response under defined conditions. One does not replace the other.
| Service | Typical stage | Main question |
|---|---|---|
| Hydrogeological/geophysical survey | Before drilling | Where is a defensible target for a proposed borehole? |
| Borehole drilling and logging | During construction | What formations and conditions are encountered? |
| Test pumping | After construction/development | How does the completed borehole respond to pumping? |
| Pump selection | After performance information is available | What pump duty fits the source and delivery needs? |
See the borehole drilling process and services overview for how the stages connect.
Illustrative survey workflow
This graphic represents workflow emphasis, not measured field data or guaranteed results.
| Workflow stage | Illustrative emphasis |
|---|---|
| Site and project brief | 85/100 |
| Field investigation | 95/100 |
| Interpretation | 90/100 |
| Reporting and recommendations | 80/100 |
Values are illustrative only; they are not a technical scoring method.
How survey planning connects to borehole costs
Hamiki’s published starting guide lists hydrogeological surveys from KSh 45,000. Confirm the final scope and quotation for the site and requested deliverables. Drilling costs are separate and vary with method, geology, depth, casing and construction requirements. The survey fee should not be confused with drilling or equipping costs.
Read the borehole drilling cost guide for published planning figures and request a written quotation for your project. Cost, groundwater occurrence, depth and yield should not be guaranteed from a general website estimate.
| Planning item | Published guide or basis | Important note |
|---|---|---|
| Hydrogeological survey | From KSh 45,000 | Confirm scope, site and deliverables in the quotation. |
| Borehole drilling | From KSh 6,500 per metre for stated suitable conditions | Actual cost depends on geology, method, casing and site factors. |
| Pump, solar and storage | Quoted separately | Selection follows borehole performance and system demand. |
Preparing for a site survey
To help scope the investigation, prepare the following where possible:
- County, nearest town, directions and a site pin or sketch.
- Intended water use and realistic daily demand.
- Information about nearby boreholes, if known, without assuming they predict your result.
- Site access details and known restrictions or underground services.
- Existing reports, borehole records or previous investigation results.
- Preferred timing and the person who can provide access.
If a borehole already exists, explain whether you need a new site investigation, a review of records or a performance assessment. This avoids confusing survey work with borehole inspection or test pumping.
What a survey cannot guarantee
A survey cannot promise that a borehole will encounter groundwater at a particular depth, deliver a fixed yield or produce water of a specific quality. Those outcomes depend on actual subsurface conditions and must be confirmed through drilling, appropriate testing and, where required, water-quality analysis. Geophysical data supports interpretation; it does not remove geological uncertainty.
A clear scope should state the survey method, area covered, deliverables, recommended target and limitations. It should also make clear whether drilling, permits, laboratory water testing and test pumping are included or separately quoted.
Hydrogeological survey FAQs
How much does a hydrogeological survey cost in Kenya?
Hamiki’s published guide starts from KSh 45,000. The actual quote depends on the site and agreed scope. Drilling, testing and pump installation are separate unless the written quotation states otherwise.
Does a survey guarantee water?
No. A survey helps assess groundwater potential and recommend a drilling target, but actual depth, yield and water quality can only be confirmed through subsequent drilling and appropriate testing.
What is a geophysical survey for borehole drilling?
It uses measurements of physical properties of the ground, interpreted with site context, to help assess subsurface conditions and identify a recommended target.
How long does a survey take?
Timing depends on site access, scope, field conditions and reporting requirements. Ask for the expected schedule when confirming the quotation.
Can you survey land before buying it?
A survey may help inform a groundwater development decision, subject to access and agreed scope. Consider it alongside intended demand, access, legal requirements and project costs.
What happens after the survey?
The findings can inform drilling plans. Actual formations are recorded during drilling. Once developed, test pumping helps assess performance and inform pump selection.
Can a survey tell me the exact borehole depth?
It can support a recommended drilling target and planning assumptions, but cannot guarantee final depth. Construction decisions respond to formations encountered and borehole design.
Author: Hamiki Engineering Editorial Team. Technical review: Hamiki Engineering team. Practical insight: survey recommendations should be recorded with methods and limitations, then checked against actual drilling and test-pumping evidence. Last updated: October 2026.