Culverts are among the most challenging assets to inspect and survey. By their nature, they are confined, dark, water affected and often unsafe for human entry. Yet they play a critical role in flood management, drainage, transport infrastructure, and network resilience.
Despite their importance, culverts are frequently under inspected due to the cost, complexity and risk associated with traditional manned entry methods.
The Challenge with Traditional Approaches
Historically, culvert inspections have relied on confined space entry, partial drainage, or limited visual surveys from access points. These approaches can be disruptive, time-consuming, and inherently hazardous, often providing only a partial understanding of asset condition.
As climate change drives more frequent and severe weather events, the resilience of drainage infrastructure has never been more critical. Asset owners need safer, more repeatable ways to understand the true condition and capacity of these structures.
A Modern, Integrated Survey Solution
On a recent project, ProDroneWorx delivered a full culvert survey using a combined confined space drone and terrestrial laser scanning approach, removing the need for manned entry entirely.
A confined space drone was deployed to capture high resolution visual imagery along the length of the culvert, allowing engineers to assess:
- Defects
- Joint condition
- Debris accumulation
- Signs of deterioration
In addition to imagery, the drone also captured a 3D point cloud from its onboard slam based laser scanner in areas that were inaccessible to static scanning methods.
Strengthening Accuracy with Terrestrial Laser Scanning
To strengthen the geometric accuracy of the dataset, we supplemented the drone survey with terrestrial laser scanning mounted on an inverted tripod. This setup allowed survey grade scans to be captured from fixed control locations within the culvert at the inlets, outlets and accessible chambers.
These high accuracy control scans were then integrated with the drone data significantly improving overall confidence in the geometry.
By combining both datasets, ProDroneWorx was able to produce a high density, spatially accurate 3D point cloud representing the culvert.
Engineering Insight – Without Returning to Site
The resulting dataset enabled engineers to:
- Assess deformation
- Measure sediment build-up
- Evaluate structural condition
- Verify clearances and clearances
All from the office without returning to site.
The resulting dataset also provides a digital baseline allowing future inspections to be compared directly and deterioration to be monitored over time.
Key Advantages
This integrated approach delivered clear and measurable benefits:
- No confined space entry, dramatically reducing health and safety risk
- No isolation or drainage required, keeping the asset operational
- Accurate, measurable data suitable for engineering assessment
- A digital record to support proactive asset management
Smarter surveys. Safer outcomes. Better data.
To find out more, visit: https://www.prodroneworx.co.uk
(Image – ProDroneWorx)