Le Gave de Pau River Flood Mapping. Data Delivery Without Software
In October 2015, a series of violent storms swept the South of France. The intense runoff from the Pyrenees mountains caused severe damage along Le Gave de Pau, changing the course of the river significantly.
In order to quickly assess the extent of the damage, in a real, measurable, geospatial sense, “The Union” (the local government body in charge of the embankments) looked for a UAV solution. Manned aerial or satellite data would not provide the required resolution, would be affected by cloud cover and be less economical on a project of this scale. The Union commissioned Drones Imaging (a geospatial data company) in partnership with AIR CITY Diagnostic (a French certified UAV operator) to acquire accurate spatial data of the devastating effects of the flood.
Well equipped to collect and process data of this kind, the team set to work. Not restricted by cloud cover as with traditional aerial or satellite operations, the project was flown the day after commissioning and the data delivered after two days.
The study focused on 8 different parts of the river for a total length of about 10km. From high resolution geo-referenced aerial images, a 3D digital surface model was produced, rendered with the orthophoto image. This resulted in a spatially accurate model with spectacular detail, to be used by the Union for assessment of the damage and to determine what future actions can be taken.
The Union, however, are not geospatial experts and don’t run a GIS system to analyze data like this. They required some basic access to the data, to view changes in the river and measure the extent of those changes.
Enabling the end user to access and utilize this data is the challenge currently faced by many in the industry. Drones Imaging was able to deliver this high resolution, spatially accurate, 3D data to their client, enabling them to view in 3D, digitize and measure features on the model, without any software.
“Our principal business is the production and delivery of geospatial data for all types of end customers: very small companies to major accounts. So, we are aware of the problems of big data transfers and customers who do not have software solutions (GIS) or computer systems tailored to geospatial deliverables.” Explains Loïc Hussenet, CEO & founder of Drones Imaging.
Drones Imaging supplied The Union with a series of eight orthomosaics (10GB in total), a digital terrain model and vector digitizing on the model. Normally this data would have been sent via ftp or physical flash drive in the mail, to be loaded onto the client’s computer and accessed with GIS software. In this case, the people that needed the data were not GIS experts but executive, operations, and administration personnel.
“Considering the volume of data to transfer (orthomosaics, plus digital terrain and markups), we decided to deliver our data using 4Dmapper. This offered a turnkey solution to the client. They received their high resolution 3D data bundled in a platform for visualization and exploitation, without downloading the data or operating a local GIS, something that the customer does not always have.”
Below use the online viewing of the 4DMapper browser or switch to full screen, and enjoy.
Equipped with their local fiber optic broadband, Drones Imaging uploaded the data into 4Dmapper in about ten minutes, where it was automatically processed for streaming. They were then able to immediately share the data with the Union and it’s colleagues via a simple email. The 3D data, and platform to access it, was delivered with just a URL, to be opened in the client’s browser. No software, no data, just a browser.
The customer was at first surprised, and then quickly embraced the user interface, with the capacity to view in 3D, blend imagery with background data, measure and digitize, all on their browser. In turn they could share the data with the various internal and external services involved in the project, including the City of Pau technical services.
“At 4DMapper, our focus is leveraging the value of geospatial data by enabling access to the people that need it; executives, stakeholders, operations personnel and so on. We make it easy to stream big 3D geospatial data.” explains Rob Klau, Director of 4DMapper.
The boom in acquisition technology with UAVs, laser scanners and high res satellite and aerial imagery means more data, in 3D, at higher resolution, and more often. Enabling access to this data is essential, with simple delivery, visualization and measurement tools, to empower the people who need to use it.
“In this case, dissemination and exploitation of our data was almost immediate for the client and its partners. Today we are in talks with the City of Pau to work on other projects” highlights Loïc Hussenet.
Demonstration with Rob Klau