Urban Drone Key Tool at Peachland Landslide
After a recent landslide in BC’s Okanagan region, Urban Systems had a unique opportunity to use drone technology.
On January 6th, a landslide occurred within the district of Peachland on Renfrew Road, which parallels Highway 97 adjacent to Okanagan Lake. The slide caused debris to fall onto the Highway 97 corridor, completely blocking the southbound lane and resulting in a temporary highway closure.
Because the landslide affected the Highway 97 (under the purview of the Ministry of Transportation) but also Renfrew Road (under the jurisdiction of the District of Peachland) both groups had to work together in tandem and quickly. A number of safety concerns were at play, including the potential risk of this active slide having a second release and putting highway users at physical risk. The Ministry brought in a geotechnical engineer, and the District of Peachland contacted Urban Systems to see if we could be of assistance on a technical and strategic level.
The landslide on Renfrew road itself took out the only travel lane and with that the main municipal sewer line for that subdivision, which served approximately 40 homes. The road dropped down 10-15 meters it was completely blocked off to passage of any and all traffic through that site. Urban Systems’ Grant Lachmuth is a Strategic Advisor to Peachland, and also recently retired from the Ministry of Transportation and Infrastructure.
“The immediate concerns for the District of Peachland were site safety and dealing with the completely severed sewer line—we did not want sensitive material outflowing down the slide, which could have created environmental risk to Okanagan Lake,” explains Grant.
After working with the Ministry to get Highway 97 fully opened (it was approved to be driven on by end of day January 6th) Grant and his team began moving to the investigation of what caused the slide.
Here is a quick one minute video showcasing the footage captured by our drone.
The Investigation Begins
Initially, the team couldn’t enter the physical slide area itself because of the potential for further risk and safety to personnel, so they did visual inspections from down on the highway looking up, and from Renfrew looking down onto the slide. They could see significant water seepage coming from the scarp face of the landslide and knew that sub surface ground water was one of the major contributing factors of the event. But they knew they needed to get a better view of that groundwater source to better assess how it was contributing to that landslide—that’s where the drone came in.
Grant reached out to one of Urban Systems’ drone pilots, JingJing Dou a Geomatics Project Associate, who flew out from Edmonton to Peachland to help.
But before the flight could happen, it had to warm up. It is generally not recommended to fly drones in colder than -10 C weather due to significant reduction in battery life. The area was experiencing temperatures around -12, but they anticipated a daytime high on January 13th of around -7, so the flight date was set.
Once the date was booked, JingJing had to submit her drone flight plans to Transport Canada and make sure Urban was in full compliance with all safety and regulatory acts and policies. Written notification was provided to all residents living adjacent to the slide.
On the day of the flight, JingJing initially took overhead video of the entire site to get a better assessment of where the slope had failed and make sure there was no further risk in adjacent areas. She then gathered survey data with the drone to do cross sections and 3D modelling of the slide site.
“The drone gathered the intel we needed to produce a very fulsome 3D model that showed exactly the shape and retrogression of the problem area. That was so helpful for us in deciding how to rebuild and re-establish the slope,” says Grant.
He adds that historically, a landslide of this significance would be dangerous to investigate. “In my day in the geotechnical engineering field landslides like this would have a much higher level of personal risk in investigating. But the drone was able to provide much more detailed technical information in a much safer fashion.”
Seeing is Believing
Within 24 hours of producing the viewable format, the team was able to take the footage to the District Operational Manager and Mayor and Council of Peachland to show them visually what the problems and solutions were.
“They were nothing short of amazed at the quality of the work and the technical information. The fact that we could move that 3D model around visually on a screen and show magnitude and contributing factors of the slide and magnitude of work in recovery phase—they were absolutely thrilled with what we produced and also with the cost, which was very reasonable.”
Jingjing says one of the most interesting parts of this project was the opportunity to demonstrate the quality of the work, and let clients see that UAV is not only about taking good looking aerial images.
“We can do so much with this tool. 3D modelling, Orthomosaic, cross sections, contours, volume calculation, 4K video, and a lot of other things. It is very exciting thinking about the fact that the data we were able to deliver within such short turnaround time and play a significant role in making a million-dollar decision. It is a perfect example to show off the power of accurate geospatial data.”
Grant echoes her statements, and says that this project showed that drone work is an area of great opportunity for Urban Systems. “We are excited to pursue this and offer it as a service to many other clients as we go forward.”
View a 3D Model of the Peachland landslide.
Thanks to the information gleaned from the drone, a business case was created to present to Emergency Management British Columbia. There were great visuals of the geo-hazard site and what happened as well as the nature of the response and recovery phase. As a result they approved their participation in the response and prepared to consider contributing funds up to 80% of the recovery phase of rebuilding, which is huge for Peachland, small community with a limited operating budget.
Look up.. up..up..The future looks bright for drones at Urban.
For more information about our Unmanned Air Vehicle (UAV) services visit our new UAV webpage.