Rethinking Confined Space Culvert Inspections
Confined space inspection has always carried risk. Culverts, tunnels, tanks and other enclosed structures are, by definition, places people weren't meant to be — and every traditional method of inspecting them starts from that problem. A standard confined space entry means permits, atmospheric monitoring, a trained entry team, a dedicated attendant at every access point, and frequently traffic management to close off the site while the work takes place. All of that has to happen before anyone even establishes whether there's a defect to find.
ProDroneWorx carries out confined space inspections differently. Using the Elios 3 collision-tolerant drone, we recently completed a full internal survey of a culvert for a client — with no traffic management required, no personnel entering the structure, and no one entering the water.
Why Confined Space Entry Carries So Much Risk
Culvert and confined space inspections sit near the top of the risk register on most infrastructure projects, and for good reason. Poor air quality, restricted movement, limited visibility, and the difficulty of extracting someone quickly in an emergency all combine to make manned entry one of the higher-hazard activities in asset inspection work. Add water ingress, common in culverts and the risk profile increases further, along with the logistics: rescue plans, additional supervision, and often road or site closures just to create a safe working perimeter.
None of this is a criticism of traditional methods, they exist because, until recently, there wasn't a credible alternative for getting usable inspection data out of these spaces. That's what's changed.
How the Elios 3 Removes the Need for Entry
The Elios 3 is purpose-built for exactly this kind of environment. Its collision-tolerant cage lets it fly through tight, awkward, GPS-denied spaces and make contact with walls, pipework or debris without losing stability or crashing, something a conventional drone simply can't do. That means it can go into a culvert, tank, or duct and capture high-resolution visual data of the entire internal structure while every member of the team stays outside, in daylight, with full communication and no atmospheric risk.
For this inspection, that translated directly into eliminated risk categories: no confined space entry procedure, no requirement for standby rescue arrangements inside the structure, no one near or in the water, and no need to implement traffic management to secure the site. The survey was completed faster than a manned entry would have allowed, and the client received a complete, high-quality internal record of the culvert's condition to support their asset management and any remedial planning.
What This Means for Asset Owners and Contractors
For clients managing culverts, drainage infrastructure, tanks, or other confined assets, the takeaway is straightforward: a full condition survey no longer has to mean putting people inside the structure. Drone-based confined space inspection using platforms like the Elios 3 delivers inspection-grade imagery and data while removing the highest-risk elements of the job entirely, not just mitigating them.
This is also increasingly relevant for contractors managing their own risk assessments and method statements, being able to specify a drone-based confined space survey as a first option, rather than defaulting to manned entry, can materially change the risk profile and cost of a project before a single permit is raised.
Get in Touch
ProDroneWorx carries out confined space and hard-to-access structure inspections across culverts, tunnels, tanks, bridges, viaducts and similar assets using the Elios 3. If you have a confined space or difficult-access inspection coming up, it's worth talking to us before a manned entry is planned.
