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Transforming Wastewater Inspections: Drones vs. Traditional Methods

Transforming Wastewater Inspections: Drones vs. Traditional Methods

Last updated on

5th May

Routine inspection of wastewater infrastructure – from underground pipes to large tanks and clarifiers – is critical for safety and environmental compliance. Traditionally, utilities have relied on confined-space entry, scaffolding, rafts or sled-mounted cameras, and even complex robotic crawlers to inspect sewers, digesters, and clarifiers. These approaches are time-consuming, costly, and pose serious risks to workers. In contrast, modern drone platforms like Flyability’s Elios 3 enable remote, collision-tolerant aerial inspection. The Elios 3 is purpose-built for GPS-denied, confined environments, carrying high-definition cameras and sensors into spaces where humans cannot go. This article examines both sides of the equation – the challenges of traditional inspection and the capabilities of the Elios 3 drone – to highlight how drones are revolutionising wastewater utility inspections.

Traditional Inspection Methods and Challenges

Wastewater facilities often have many inaccessible or hazardous spaces. Digestion tanks, circular clarifiers, lift stations, and buried sewer lines may require workers to enter tight, enclosed areas. For example, OSHA notes that sewage treatment plants contain numerous permit-required confined spaces (digesters, holding tanks, pump stations) with hazards like toxic gases (e.g. hydrogen sulphide), low oxygen, chemicals, and drowning. In practice, inspectors face dangers such as asphyxiation, explosions (from flammable gases), engulfment, and slips/falls when entering sewer pipes or tanks. Respiratory protection (SCBA), forced ventilation, and extensive training are mandatory. Even with precautions, hundreds of workers die annually in confined-space accidents,, underscoring the high stakes of these jobs.

Beyond safety, conventional inspections are labour-intensive and costly. A confined-space entry typically requires multiple trained personnel (e.g. two entrants plus a safety attendant) and lengthy preparations. Pre-cleaning or dewatering of a tank is often needed before anyone can enter safely, and complex scaffolding or ladders may be erected just to reach inspection points. These setups can easily cost thousands of dollars per mobilisation, especially when equipment rentals and union labour are involved. For example, one plant spent about $2,400 each time temporary scaffolding was rented and assembled for routine maintenance.

Conventional methods are also slow and disruptive. A sewer camera mounted on a raft or sled can only drift with the flow – inspectors cannot control its direction, leading to unreliable coverage. Manually inspecting a long pipeline or large tank can take days of work, shutting down equipment and diverting flows. In contrast, labour-saving technologies (like mechanised cleaning trucks) have evolved to reduce confined entries, but these still involve heavy equipment and don’t fully eliminate risk or cost. In short, traditional inspections trade high cost and high risk for detailed data, which is a difficult bargain in a modern utility budget and safety environment.

Hazards: Toxic gases (H₂S, CH₄), low O₂, chemicals, drowning, falling debris.
Personnel: Multiple crew required (entrants + attendants); 80+ hours of confined-space training.
Preparation: Dewatering, cleaning, ventilation, permitting – all add time and expense.
Equipment: Scaffolding, winches, boats/rafts, harnesses – costly and time-intensive to use.
Time: Inspections often take days; pipelines may need flow bypass.

Overall, these constraints mean inspections are done less frequently than ideal, increasing the risk of undetected problems.

Enter the Elios 3 Drone: A New Inspection Paradigm

The Elios 3 is a purpose-built indoor inspection drone designed by Flyability to operate in confined, GPS-denied spaces. It features a collision-tolerant cage, bright lighting, and advanced sensors (4K camera, thermal camera, LiDAR, distance sensor). The drone’s compact size lets it navigate pipes, ducts, tanks and tunnels as small as a few feet across. Key design elements include:

Collision-resilient cage: Propellers are enclosed in a spherical metal cage. If Elios collides or even flips upside-down, it can recover and keep flying.
IP44-rated design: Built to withstand dust and occasional water splashes, essential for sewers or wet tanks.
High-performance sensors: A 4K, 180°-field-of-view camera and powerful oblique LED lights allow detailed imaging of walls and sediment even in total darkness. Optional payloads include a LiDAR mapper (for 3D scanning) and a thermal imager.
Gas sensing: An optional gas sensor payload can detect flammable and hazardous gases (e.g. hydrogen, methane) in real-time during flight, adding a layer of safety awareness.
Autonomous features: The Elios 3 monitors its radio signal and, if it loses link, will automatically return along its path until it regains connection.

Together, these features make Elios 3 uniquely capable of rapid visual inspection inside wastewater assets. Instead of setting up a scaffold or sending a human, a pilot can launch the drone from outside a manhole or tank lid and guide it through the interior, live-streaming video to safety operators. The process requires minimal downtime – often no need to empty or clean the chamber first – and yields high-resolution images and video for analysis.

Safety and Operational Advantages

Enhanced Safety: By keeping humans on the surface, Elios 3 eliminates the primary confined-space hazards. Inspectors avoid exposure to low oxygen or deadly H₂S gas, and risk of slips, falls or engulfment is essentially zero. As one Flyability blog notes, using drones “vastly improves safety for the inspection process” since entry is no longer required. Major industrial users echo this: BASF and Dow have deployed drones “to keep workers off scaffolding and out of tanks where potential injuries lurk”. In fact, OSHA statistics underscore the point: 166 U.S. workers died in confined spaces and 887 by falls in 2017 alone. These sobering numbers reflect the kinds of accidents drones can help avoid.

Reduced Personnel and PPE: A conventional sewer check might need two entrants plus a safety attendant; Elios 3 typically requires just one pilot and one safety observer on the ground. Training requirements shift from confined-space certification to drone operation certification, which is far less burdensome. There is also no need for bulky SCBA gear or harnesses inside the dark depths – the drone’s lights do the illuminating. One sewer authority found that just two people could now inspect what used to require three. This not only cuts labour costs but also shortens prep time for each inspection, since fewer personnel must be suiting up and standing by.

Access to the Inaccessible: The Elios 3 can fly over obstructions or through tight bends where other methods fail. Veolia Water notes that Elios drones “provide a better visual inspection” by flying above debris and obstacles. Indeed, assets “that they couldn’t [inspect] before” – such as aeration basins or storage tanks with no safe entry – can now be assessed by drone. The drone’s stability even in drafty flows (inside sewers) means it can hover steadily in currents that would knock a raft around. Powerful onboard lighting ensures that even water-covered floor or walls can be seen in detail. In effect, Elios 3 extends an inspector’s eyes into every corner of a facility without endangering personnel.

Efficiency and Cost-Efficiency Gains

Beyond safety, one of the most compelling advantages of drone inspection is time and cost savings. Multiple studies and case reports show dramatic improvements when switching to Elios 3:

Faster Inspections: Drones can often complete in a single day what used to require multiple crews and days of work. One industry report found that many jobs “that would’ve taken human workers days take drones only a few hours”. Because the Elios 3 can be deployed almost immediately (no scaffold erection or flow bypass needed), the overall inspection cycle is greatly shortened. Veolia observed that Elios drones inspect assets twice as fast as traditional methods. In practical terms, they noted “half the time” needed for the same coverage.
Lower Costs: Multiple users report ~40% cost reductions in inspection programs when using the Elios drone. This figure arises from savings on labour, equipment rental, and downtime. For example, if two workers and gear can be replaced by one operator and a drone, the per-hour labour cost is cut roughly in half. Additionally, by avoiding costly confined-space setups (ventilation, bypass pumps, etc.), each inspection becomes cheaper. In sewer pipelines, an inspection cost metric (dollars per meter) was cut by 40% with Elios.
Elimination of Unplanned Delays: Traditional inspection often requires cleaning the sewer or tank before entry; with a drone, these preparations can be skipped. As Veolia explains, “we are able to inspect assets without necessarily cleaning the collectors prior to our intervention. As a consequence, we have a much faster intervention.”. In effect, inspections can occur on short notice (for urgent issues) or during normal operations without lengthy shutdowns, increasing overall uptime of the facility.
High-Quality Data: The Elios 3’s camera and lights provide extremely clear images of welds, cracks, corrosion, or sediment. Importantly, the drone’s data can be geotagged and integrated with inspection software. Veolia now incorporates Elios data into digital reporting tools for compliance with regulatory standards (e.g. EN 13508 for sewer inspection). Detailed video and 3D mapping also improve maintenance planning: defects are spotted sooner and located precisely. One benefits of drones is that they “fly over obstacles and provide a better visual inspection” which allows planners to “identify future issues before they occur”.

In summary, drone inspections turn a slow, laborious process into a rapid, repeatable operation. Even at a purchase price of tens of thousands of dollars, the payback can be quick. Users like Dow and BASF note that despite drones costing up to $250k, the machines “not only save lives, but cut costs for companies” over time. With these efficiency gains, routine inspections can be done more frequently and with better data, ultimately reducing long-term repair costs and preventing emergencies.

Case Studies and Metrics

Veolia Water (France) – As a market leader, Veolia has embraced Elios drones across its operations. In 2023 they updated their fleet with the Elios 3, calling it “an irreplaceable tool… a new member within the team that we use every day”. Their data confirms what many users see: ~40% cost reduction per metre and inspections completed in about half the time. Veolia’s team pointed out that two workers and a supervisor (human team) were replaced by one drone pilot and an observer in many cases. They emphasize that drone inspections now begin and end much faster – setup is simply opening a manhole and flying in, versus spending hours on safety preparation.

Barcelona Sewer Rescue – In a dramatic example, the City of Barcelona used an Elios drone (through Flyability partner Flind) in a deep sewer emergency. The collision-tolerant drone surveyed a 55-meter-deep pipeline that had been undermined by sand erosion. Ground crews could not safely enter the pipe due to risk of collapse. The Elios captured the damage extent and helped re-route flows to prevent a spill. Flind’s director Kovesi noted that this case is “emblematic” – it was literally lifesaving. Even in routine situations, Flind finds that Elios inspections are “twice as efficient as human inspectors – and 40% less expensive per meter”. He adds that in very deep pipes (tens of meters), drone use becomes 8–10 times more efficient than humans, since winching people down becomes extremely burdensome.

Other Industries: While not wastewater-specific, numerous industrial case studies reinforce the trend. In mining, power, and chemical plants, Elios 3 has cut inspection times by similar percentages (50–90%) and yielded major safety benefits. An oil refinery needed only 8 hours (instead of 8 days) to inspect a steam condenser with Elios. In all these cases, the common themes are less time, less risk, and high data quality.

Integrating Drone Inspections into Operations

For wastewater utility managers, adopting drone inspection means planning for new workflows and training. The operational value of the Elios 3 extends beyond single inspections:

Routine Condition Monitoring: With easier setup, drones make it feasible to inspect structures (digesters, clarifiers, pipelines) on a regular schedule rather than only after problems occur. Predictive maintenance improves when facilities have up-to-date visual records.
Quick Response to Alarms: Facilities with remote sensors (level sensors, gas alarms, etc.) can dispatch a drone immediately when an alert sounds, to verify conditions without risking a person.
Documentation and Collaboration: All video and images from the drone can be logged in asset management systems. Cloud-based tools allow engineers in the office to review footage in real-time as it is captured, aiding collaborative decision-making.
Regulatory Compliance: Detailed drone surveys help meet inspection standards (sewer norms, dam safety, etc.) with clear evidence. For example, Veolia reports faster delivery of compliant reports thanks to Elios-collected data.

Cost of Adoption: Although the initial investment in a drone, training, and software may seem significant, many utilities discover that a single well-deployed drone can pay for itself within just 1-2 years. This return on investment comes through savings in labour costs, reduced overtime, and minimising delays. Additionally, drones help to lower liability insurance costs by significantly reducing the risk of accidents.

The training process is designed to be straightforward and efficient: pilots start with a flight simulator and quickly progress to hands-on missions under expert supervision. With the added benefit of product handover flight coaching, teams are fully equipped to maximise the drone’s capabilities from day one. Unlike traditional human-entry crews, drone teams are lean, agile, and capable of completing inspections faster and more safely.

Conclusion

In short, the Elios 3 transforms wastewater inspection from a slow, dangerous chore into a streamlined, digital process – a clear example of how drones are bringing unprecedented safety and efficiency to industrial inspection.

By eliminating the need for human entry, it drastically reduces liability and enables inspections that were previously impossible or impractical. Real-world results speak for themselves: Veolia Water (France) reported ~40% cost savings per metre and inspections completed in half the time after upgrading to the Elios 3. Wastewater utility managers can leverage this technology to build stronger maintenance programmes, ensure regulatory compliance, and protect their workforce.

The Elios 3, exclusively supplied through Coptrz, pairs cutting-edge design (caged rotors, high-intensity lights, advanced sensors) with dedicated service and support, ensuring your operations achieve rapid ROI, enhanced safety, and unmatched operational resilience.