Drones are cost-effective tools for monitoring job sites before, during, and after construction. They provide precision mapping, faster data collection, smarter decision-making, visual documentation and enhance worker safety. State DOTs are utilizing drones for various applications, saving time and costs.
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Unmanned aerial vehicles, or drones, are important devices on job sites, not only in planning a project and monitoring its progress but as a tool for tracking pavement conditions after the project has been completed.
Unmanned aerial vehicles (UAVs), or drones, are more commonplace tools on the job site as they are growing more sophisticated in technology and application.
UAVs have proven to be a critical tool over the past couple of years in assessing site conditions before and during construction. After the project is completed, these devices are valued for monitoring pavement and structural conditions. Savings, safety, mobility and reliability are incentives for their growing use.
An analysis of available information was undertaken to identify drone applications, classify benefits, address challenges and suggest potential solutions.
The authors sought to understand the current body of knowledge covering the usage of drones for roadway condition monitoring (D-RCM).
Taraneh Askarzadeh, Raj Bridgelall and Denver D. Tolliver wanted to determine how that might help address ongoing issues.
According to an ASCE abstract, the trio explored the implications for new theories, management and impacts to society that arise from D-RCM.
Cost and time savings, safety enhancements, improved mobility and reliability are the primary drivers behind D-RCM adoption, said ASCE.
Applications categories included condition monitoring, situation assessment, network mapping, asset monitoring and construction inspection. Challenges, such as visual line-of-sight maintenance, limited flight time, payload capacity and engineering errors were found.
Emerging potential solutions included terrain-following features, optimizing battery capacity-weight balance and employing trained personnel.
"Importantly, the study reveals considerable cost benefits and impressive return on investment of up to 980 percent," said the abstract.
This revelation positions drones as "a promising, cost-effective tool for infrastructure management."
The technology has "profound implications for theory, management and societal impacts of D-RCM applications."
Monitoring Road Surfaces From Above
Aerial photography company The Drone Life would agree about the profound implications.
The company sees major benefits to UAV technology for road and highway construction that can be applied just as well to tracking pavement conditions.
Christian Allred believes drones are revolutionizing highway construction by offering the industry the capability to make informed decisions on projects.
In a blog post for The Drone Life, Allred said crews are able to precisely conduct site surveys, monitor earthwork progress and oversee pavement placement.
"Real-time insights from UAVs not only enhance productivity but also improve safety and reduce project costs," he said, offering a top five benefits list:
1. Precision Mapping and High-Resolution Data
Drones are transforming how engineers assess terrain before road construction even begins, said Allred.
With advanced aerial surveying capabilities, UAVs can capture highly accurate, sub-centimeter-level data.
The data offers crucial insights into soil conditions, elevation changes and potential obstacles to improve planning and reduce unexpected construction costs.
"Before asphalt paving begins, drones ensure the ground surface aligns with design specifications," said Allred. "They even optimize haul route planning, reducing fuel costs and project timelines."
Leveraging physical markers placed across the site, drones achieve survey-grade accuracy once possible with costly traditional surveying methods, he said.
2. Smarter, Faster Decision-Making
Drones provide real-time aerial insights that significantly enhance on-the-ground decision-making.
By hovering above a construction site, UAVs can monitor supply levels, track equipment status and identify inefficiencies. The devices offer project managers the information to reallocate materials, report damages and adjust schedules before small issues escalate into costly delays.
"With live drone feeds, multiple team members can simultaneously review construction progress, ensuring quick, tactical decision-making," said Allred. "A single drone flight can detect errors in fine grading or equipment placement, allowing crews to make corrections immediately."
And for more in-depth analysis, drone data can be processed with advanced software within hours, offering teams precise insights for ongoing adjustments.
Drones also serve as a valuable legal safeguard. If a safety dispute arises timestamped drone footage can verify site conditions on any given day.
"This documentation not only protects contractors from liability but also reinforces a strong commitment to site safety," said Allred. "Ultimately, drone data helps teams catch mistakes early, reduce costly rework and keep projects on track."
3. Faster Data Collection
One of the main benefits of using drone technology in road construction in general is speed.
To send an engineer on foot to collect the same data with a handheld camera can be an incredibly slow process, Allred said.
"Drones can cover large stretches of road and they can capture far more data from various angles."
Another reason drones can collect data faster is that they are not slowed down by on-the-ground hazards, he added.
"Site material, equipment and traffic can get in the way when you're on foot," said Allred. "But drones can map entire corridors, problem-free, from the air."
"In the end, road construction surveys that used to take several weeks can now be done in a matter of days with drones," he said. "And drones can give you more frequent reports while staying incredibly cost- and time-efficient."
4. Visual Documentation
UAVs also provide better visual documentation of each layer of the road as it is laid.
Capturing aerial drone footage of each one before moving on to the next allows you to keep a detailed visual progress record as you go, said Allred.
5. Enhanced Worker and Site Safety
"Drones play a crucial role in improving worker safety and site security," he said.
By capturing aerial data, UAVs eliminate the need for personnel to inspect hazardous areas, reducing the chance of accidents.
"Their bird's-eye view also helps crews identify and mitigate potential dangers before they escalate," said Allred.
This mitigation can result in fewer injuries, lower liability and reduced insurance costs for the contractor or the site owner.
Chris Grazioso of Dart Drones said when they first landed in construction, UAVs were used by private entities for photography, videography and mapping.
As technology grew more sophisticated, drones became the go-to tools for public entities such as state DOTs.
These agencies are "now using them more than any other public entity in the country," said Grazioso, an instructor of the UAV training company.
State DOTs are using drones for an array of applications including bridge inspections, accident assessments, roadway surveying and risk identification.
"DOTs have many jobs, and each year they and their contractors are figuring out how to utilize drones in their projects," Grazioso said. "Today, DOTs are paving the way for drones to be used more effectively while keeping them under safe regulations."
North Carolina's DOT received the first-ever waiver from the FAA in 2022 to fly beyond visual line-of-site for bridge inspections. This expanded not only the applications but also how the drone executes these applications, including pavement condition monitoring.
Grazioso's laundry list of UAV possible uses by state departments of transportation is extensive itself. The devices can track construction projects, traffic patterns, accident clearing, road congestion, surface deformation, flooding, landslides and rockslides.
They can be used in inspections of routine maintenance, bridge supports and decks, confined spaces, light poles, road damage and equipment condition.
For data gathering, UAVs can be used in land surveying, asset inventory and management, operational and scientific research and emergency response plans.
Grazioso pointed out that many operations conducted by DOT employees and contractors are inherently dangerous.
"The implementation of drones can reduce the risk involved in these types of operations," he said. "The less time that employees spend in hazardous work areas, the lower the degree of risk."
Plus, drones can reduce the risk to the public by allowing jobs to be completed faster than with traditional methods.
"This reduces the time a work zone is open, which in turn minimizes the number of public individuals entering," said Grazioso.
The Minnesota Department of Transportation uses drones to inspect structures previously not inspected.
That was due to the hazards imposed by traditional methods, said Grazioso. "Drones have improved their safety margins considerably."
These UAVs can be launched on short notice, improving both project flexibility and turnaround times.
"Minnesota DOT's typical small unmanned aircraft system [sUAS] workflow has a turnaround time of 48 hours start to finish," said Grazioso.
That turnaround time includes defining a flight plan, flying and post processing the data.
A standard bridge inspection uses costly inspection vehicles, ranging from $250,000 to $500,000 and requires a multi-day effort.
Minnesota DOT has calculated a 40 percent cost savings using drones, said Grazioso.
"The average cost to inspect a bridge using traditional methods was $40,800. A comparable sUAS assisted inspection costs a mere $19,900."
State DOTs are leveraging the use of drones because they lower risk, manpower, equipment and time in the field while raising quality of deliverables.
Drones provide access to high-resolution data "like never before," said Grazioso.
"So, in using them, DOTs get the best of both worlds for savings and improved work." The proof is in the data," he said.
DOT reports show that drones save an average of between 60 percent and 70 percent on labor and hardware expenses alone.
"Time-wise, drones can do day-long jobs in an hour, bringing in even more savings," he said, adding bridge inspections are a common example, where the savings are among the largest of any other use-case.
Once a lengthy and dangerous process, bridge inspections are done in one-eighth the amount of time with drones compared with humans or bucket trucks.
"In addition to the time savings, the use of drones does not require bridge or road closures, turning the economic impact to the lowest states have seen," he said.
"For many DOTs, this means that the drone — as well as drone program, or the drone contractor they work with — pays for itself in savings," added Grazioso. CEG
Lucy Perry
Lucy Perry has 30 years of experience covering the U.S. construction industry. She has served as Editor of paving and lifting magazines, and has created content for many national and international construction trade publications. A native of Baton Rouge, Louisiana, she has a Journalism degree from Louisiana State University, and is an avid fan of all LSU sports. She resides in Kansas City, Missouri, with her husband, who has turned her into a major fan of the NFL Kansas City Chiefs. When she's not chasing after Lucy, their dachshund, Lucy likes to create mixed-media art.
Read more from Lucy Perry here.
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