01Constraint
300 km² of terrain with no digital baseline
Aerial Mapping · GISInfrastructure Development Authority · Public Infrastructure · 2023
GIS Aerial Survey
300 km² surveyed to centimetre accuracy in 10 days.
LiDARRTK GPSGISOrthophotoDTMDTMInfrastructure Survey
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The challenge
Complex constraints.Real-world pressure.
Before architecture and implementation, we mapped every operational blocker and business risk. These were the core constraints shaping the entire solution design.
4 critical challenges
02Constraint
Ground survey projected at 6 months minimum
03Constraint
Survey accuracy requirement of ±5 cm
04Constraint
No existing GIS data to reference or validate
What we built
A system built for the problem, not off the shelf.
We deployed a fleet of LiDAR-equipped survey drones with RTK GPS integration across the 300 km² survey zone. Ground control points were established and surveyed using dual-frequency GNSS receivers to provide the accuracy reference frame required for the project.
The survey was completed in 10 flying days across 3 weeks, including a dedicated re-flight for 18 km² of dense forest canopy that required a second pass at lower altitude for adequate ground-point penetration.
Processing produced a full deliverables package: 5 cm resolution orthophoto mosaic, digital terrain model (DTM), digital surface model (DSM), point cloud (classified), and a GIS-ready land-use classification layer — all delivered in the formats specified by the authority's engineering team.
Capabilities delivered
Every feature with a reason.
01
LiDAR point cloud survey
Dense point cloud at 40+ points/m². Ground classified from vegetation and structures for accurate DTM generation even in forested areas.
02
RTK/GCP ground control
GNSS-surveyed ground control points at 1 per 4 km² density. Survey accuracy verified: ±4.2 cm horizontal, ±6.8 cm vertical.
03
5 cm orthophoto mosaic
Full 300 km² orthorectified imagery mosaic at 5 cm GSD. Delivered as GeoTIFF tiles for GIS integration.
04
DTM & DSM generation
Bare-earth DTM and full surface DSM. Used directly for road design, cut-fill analysis, and drainage modelling.
05
Land-use classification
Automated and manually reviewed land-use classification into 12 categories. Exported as GIS polygon layer with attribute table.
06
Full GIS deliverables package
All outputs in GeoTIFF, LAS/LAZ, and ESRI Shapefile formats with metadata and accuracy reports.
Measured outcomes
Numbers that changed how they operate.
0months → 10 days
Survey completion time
0km²
Area covered
0cm
Achieved horizontal accuracy
−0%
Cost vs ground survey
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