What is a Downhole Camera Survey?
A downhole camera survey—also known as a borehole camera inspection or well camera survey—is a non‑destructive diagnostic technique that uses a high‑definition, waterproof camera to visually inspect the interior of a borehole. The camera is lowered into the borehole on a cable, and as it descends, it captures real‑time video footage of the casing, screen, gravel pack, water level, and any structural features or anomalies.
This technology has become an indispensable tool for borehole owners, hydrogeologists, and drilling engineers. It provides an "inside view" of the borehole that cannot be obtained through any other method, revealing the actual condition of the well and pinpointing problems that may be affecting yield, water quality, or equipment longevity.
In Kenya, where boreholes are often drilled in challenging volcanic or sedimentary formations, camera surveys help identify issues like fractured casing, screen clogging, scale buildup, or gravel pack displacement before they lead to costly failures. They are also used to verify the quality of new borehole installations and to plan rehabilitation work.
Why Visual Inspection Matters
Many borehole problems are invisible from the surface. A pump may still run, but yield may decline, pressure may drop, or water quality may change. Without a camera survey, you are essentially guessing at the cause. Visual inspection provides several critical benefits:
- Accurate diagnosis – rather than relying on symptoms, you can see the actual problem, whether it's a cracked casing, a blocked screen, or sediment accumulation.
- Preventive maintenance – early detection of minor issues (e.g., early stage scale buildup) allows you to address them before they become major failures.
- Rehabilitation planning – if you need to rehabilitate a declining borehole, the camera survey tells you exactly what methods (mechanical cleaning, chemical treatment, hydrofracturing) will be most effective.
- Quality assurance – for new boreholes, a camera survey confirms that the installation meets specifications and that the casing and screen are undamaged.
- Peace of mind – knowing the condition of your borehole gives you confidence in its long‑term reliability and helps you budget for future maintenance.
How a Downhole Camera Survey Works
The survey process is straightforward but requires specialised equipment and experienced operators. Here's what typically happens:
- Site preparation – the area around the borehole head is cleared, and safety measures are put in place. The pump may need to be removed to allow the camera to access the full depth of the borehole.
- Camera deployment – a waterproof camera housing (usually with LED lighting and a pan‑and‑tilt capability) is attached to a calibrated cable connected to a surface control unit. The camera is lowered into the borehole at a controlled speed.
- Real‑time viewing – as the camera descends, the operator watches the live video feed on a monitor, noting any features of interest. The camera can be rotated or tilted to get a 360‑degree view.
- Recording and depth tracking – the entire survey is recorded, and the depth of the camera is continuously displayed on the footage. This ensures that any observed features can be precisely located.
- Data analysis – after the survey, the footage is reviewed in detail. Key findings are documented, and a report is prepared with still images and recommendations.
In Kenya, many boreholes have water levels that fluctuate seasonally. Camera surveys are ideally conducted when the water level is low enough to expose the screen and lower casing, although modern cameras can also operate fully submerged.
What Can a Camera Survey Detect?
A downhole camera survey can reveal a wide range of issues that affect borehole performance. The table below summarises common findings and their implications.
| Issue Detected | Typical Appearance | Potential Consequences |
|---|---|---|
| Casing cracks or holes | Visible fractures, perforations, or missing sections | Allow sediment or contaminated water to enter; risk of collapse |
| Screen clogging | Deposits of scale, iron/manganese, or biofilm covering the screen openings | Reduced yield, increased drawdown, higher pumping costs |
| Gravel pack displacement | Voids or missing gravel sections; uneven gravel distribution | Sand intrusion, reduced well efficiency, potential screen damage |
| Scale buildup | White, yellow, or brown crusts on casing and screen; often calcium carbonate or iron deposits | Reduced flow, increased friction losses, potential pump wear |
| Corrosion | Rust, pitting, or discolouration on steel casing or pump parts | Structural weakness, leaks, potential equipment failure |
| Sediment accumulation | Sand, silt, or debris at the bottom of the borehole | Reduced storage volume, pump clogging, abrasion damage |
| Pump or pipe damage | Visible wear, missing parts, or improper seating | Inefficient operation, leakage, or complete failure |
| Water inflow zones | Areas where water is seen entering the borehole; can indicate fracture zones or aquifer connections | Confirms productive intervals; useful for pump placement decisions |
| Foreign objects | Debris, dropped tools, or other obstructions | Block flow, damage pump, or interfere with maintenance |
The ability to visually confirm these issues makes the camera survey an essential diagnostic tool for any borehole owner.
When to Conduct a Camera Survey
Camera surveys are not just for emergency troubleshooting; they are a proactive maintenance tool. Here are the key times to consider one:
- New borehole acceptance: After drilling and before pump installation, a camera survey verifies that the casing, screen, and gravel pack are correctly installed and undamaged.
- Periodic maintenance: For long‑term boreholes, a camera survey every 2–3 years helps track gradual deterioration and allows timely intervention.
- Yield decline: If your borehole's flow rate drops significantly, a camera survey can pinpoint whether the problem is screen clogging, sediment accumulation, or casing damage.
- Water quality changes: Sudden changes in taste, colour, or turbidity may indicate casing damage or contamination; a camera survey can identify the entry point.
- Before rehabilitation: Planning a borehole rehabilitation? A camera survey tells you exactly what methods (e.g., chemical treatment, high‑pressure jetting, hydrofracturing) will be most effective.
- After major events: Following earthquakes, flooding, or nearby construction, a camera survey can assess any potential damage.
In short, if you're not sure about your borehole's condition, a camera survey provides the clarity you need to make informed decisions.
Interpreting the Footage
Understanding what you're seeing in a camera survey takes experience, but knowing the basics helps you engage with your contractor:
- Clear, uniform casing – indicates good structural integrity.
- Discoloration or pitting – may signal early corrosion; monitor closely.
- White/yellow deposits – likely calcium carbonate or iron scale; may require chemical cleaning.
- Brown/red deposits – often iron or manganese precipitation; treat with appropriate chemicals.
- Visible openings in the screen – if they appear blocked or reduced, screen cleaning is needed.
- Voids in the gravel pack – indicate displacement; may require gravel pack repair.
- Water entry points – shown as turbidity or shimmering at specific depths; useful for pump placement.
- Foreign objects – can often be retrieved with specialised tools, but may require professional intervention.
A professional survey report will include time‑stamped images and a narrative description of key findings, along with recommendations for corrective action.
How WaterLink Limited Conducts Camera Surveys
At WaterLink Limited, we use state‑of‑the‑art downhole camera systems to deliver clear, actionable insights for our clients. Our approach includes:
- High‑definition, pan‑and‑tilt cameras – providing crisp, 360‑degree views even in murky water conditions, with powerful LED lighting for clear visibility.
- Precision depth tracking – every observation is accurately tagged with depth, allowing precise location of issues for targeted intervention.
- Experienced operators – our hydrogeologists and technicians have conducted hundreds of surveys and can quickly identify subtle signs of problems.
- Comprehensive reporting – you receive a detailed report with video footage, still images, a depth‑by‑depth log of findings, and clear recommendations for maintenance or rehabilitation.
- Integration with other diagnostics – we often combine camera surveys with pumping tests and water quality analysis for a complete borehole health assessment.
- WRA compliance – all our surveys meet WRA technical standards and can support your annual abstraction reporting if needed.
Whether you need a routine inspection or are troubleshooting a problem, WaterLink Limited's camera survey service gives you the visual evidence to make confident decisions.
Cost and Value of Camera Surveys
The cost of a downhole camera survey in Kenya typically ranges from KES 15,000 to KES 30,000, depending on the depth of the borehole and the complexity of the survey. For deeper boreholes (200m+), the cost may be slightly higher due to the additional cable and setup time.
When you consider the cost of a pump failure or a complete borehole rehabilitation, the camera survey is an incredibly cost‑effective investment. It can prevent major failures, reduce maintenance costs, and extend the life of your borehole. For commercial or agricultural boreholes that generate income, the avoided downtime alone can easily justify the survey cost.
Many contractors, including WaterLink Limited, offer camera surveys as part of a comprehensive maintenance package, which can provide even better value. We recommend including a camera survey in your annual or bi‑annual maintenance plan to catch issues early.
