The question comes up on almost every project brief: Can you just use a drone for this?
Sometimes yes. Sometimes no. And sometimes the right answer is both — drone for the broad picture, RTK GPS for the precise details.
Understanding when to use which tool will save you money, time, and the embarrassment of producing data that does not meet your project’s actual requirements.
Drone mapping — more formally called UAV (Unmanned Aerial Vehicle) photogrammetry or LiDAR — excels at covering large areas quickly and producing visually rich outputs.
A drone can map a 50-hectare site in a single day and produce:
These outputs are useful for planning, visualisation, volumetric calculations, progress monitoring, and environmental assessment. For communicating what a site looks like to people who have not visited it, nothing beats an orthophoto or 3D model from a drone.
Despite the enthusiasm around drone technology, there are clear limitations.
A drone flying with only its internal GPS can produce imagery that looks accurate but is positionally wrong by 1–5 metres. For most planning visualisations, this is fine. For land boundary work, engineering design, or anything that will feed legal or contractual decisions, it is not.
To achieve survey-grade accuracy from drone data, you need Ground Control Points (GCPs) — precisely surveyed markers visible in the drone imagery that anchor the photogrammetric model to real-world coordinates. Those GCPs must be surveyed with RTK GPS or total station. So even drone mapping depends on traditional survey at its foundation.
Photogrammetry cannot see through trees. If you need terrain data under a forest canopy, you need LiDAR — either drone-mounted (expensive) or airborne (very expensive). For most projects in Kenya, this means accepting the limitation or collecting supplementary ground survey data in vegetated areas.
Drone imagery cannot replace boundary survey for legal purposes. Title deed production, subdivision, and boundary disputes require licensed survey — coordinated with the Survey of Kenya — conducted with calibrated instruments and proper field procedures. A drone image showing an approximate boundary is not a legal survey document.
Kenya’s weather is generally good for drone operations, but the coast, highland areas, and certain seasons create conditions that ground flights. A project dependent solely on drone data can be delayed by weather in ways that ground survey is not.
RTK GPS survey — using a base station broadcasting corrections to a rover receiver — produces centimetre-accurate position data for discrete points and features.
It is the right tool for:
RTK survey is slower than drone mapping for large areas — a single surveyor collects hundreds to thousands of points per day, not millions — but each point has verifiable accuracy and can be specifically located to a named feature.
The most effective projects use both tools together, each doing what it does best.
A typical combined workflow for a subdivision project might look like this:
The drone handles the big picture. The RTK handles the precision work. Neither is redundant.
Drone mapping has a higher day-rate than ground survey, but covers much larger areas per day. For a 500-hectare farm, drone mapping will be significantly cheaper than ground survey of the same area. For a 0.5-hectare plot requiring precise boundary survey, a drone adds cost without adding value.
The relevant question is not which technology is cheaper but which technology produces the output the project actually requires, at the required accuracy, for the relevant area.
A good survey firm will advise you on this honestly. Be cautious of firms that push drone work on every project regardless of fit — drone data is visually impressive and easy to charge a premium for, but it is not always the right tool.
| Method | Typical Accuracy | Best For |
|---|---|---|
| Drone (no GCPs) | 1–5m horizontal | Visualisation only |
| Drone (with GCPs) | 3–10cm horizontal | Planning, volumes, mapping |
| RTK GPS | 1–3cm horizontal | Boundaries, control, setting out |
| Total Station | 1–5mm | Engineering, precise setting out |
Before commissioning any survey work, ask:
The answers will tell you quickly whether you are dealing with a competent firm or not.
ZeroPoint Geospatial operates both drone mapping and RTK survey services across Kenya. We will always recommend the method that is right for your project, not the one that is easiest for us. Request a quote.