Precision aerial topographic mapping using drones
Contour mapping (also known as elevation mapping topographical mapping) is part of the typical pre-construction planning kit for surveyors, engineers, building designers and construction managers who need to know the precise characteristics of a site before they plan what and how to build on the site. Find out more about the full range of services we provide for construction and development.
Contact us now for an obligation-free quotation for your aerial contour mapping and topographical mapping, or find out more about the aerial contour mapping process below.
Our aerial contour mapping service
Queensland Drones provides precision contour maps at intervals of 1m, 0.5m or 0.25m with centimetre accuracy even on steep and moderately vegetated sites.
These contour maps can be delivered as large format PDF files for printing, georeferenced KMZ or ESRI SHP files to load as layers into Google Earth or GIS systems and overlaid with other data, or as DWG files with X/Y/Z coordinates for import into Autocad and other design packages.
As well as building and development design inputs, our aerial contour maps can be used to identify the best location for a building site, plan the route for a driveway or access road to the building site, visualise water flows to locate the best site for a dam and many other applications.
Contour maps can be developed from aerial orthogrammetry (images captured using a drone and stitched to create a 3D model of the land), or from Lidar data if available in your area (Lidar data is available across most of South-East Qld and Northern NSW).
Aerial photogrammetry mapping is better for sites up to 120 Ha with low-medium vegetation as it can produce more closely-spaced contour maps (down to 25 cm) with high geospatial precision (1.5-2.5 cm). Trees and other vegetation can be removed through point cloud classification to provide a virtual bare earth contour model.
Lidar mapping is better for larger and more heavily vegetated sites as multiple ground returns allow more precise classification and removal of vegetation, but we can only produce contours to 1m spacing with 30-40 cm accuracy.
We can work independently or in close collaboration with your surveyor, engineer or building designer. We are not surveyors, but our outputs can be certified by your surveyor if required.
Aerial contour mapping using photogrammetry
For relatively open and bare earth sites, we recommend drone-based mapping in conjunction with precision ground control points (GCPs) for maximum contour precision and maximum flexibility in how the outputs can be used to enhance your workflow.
Our drone-based mapping uses a 20 megapixel RGB camera which can provide an effective ground sampling distance (GSD) of less than 1 cm per pixel. To put this in context, an object the size of a beer bottle cap can potentially be identified in the imagery.
To enhance the precision of our aerial contour maps, we utilise satellite-based geolocation equipment which can precisely position ground control points to an accuracy of 5 cm horizontal and 10 cm vertical (depending on location and availability of satellites on the day).
These GCPs allow us to very detailed contour maps (1 m, 0.5 m or 0.25 m spacing as needed) as well as create 3D models and point clouds with geolocation precision below 30 cm. We can also provide digital terrain models (DTMs), digital elevation models (DEMs), digital surface models (DSMs) and calculate cut/fill volumes from this data.
Queensland Drones can also provide boundary point mapping (precise locations for every node in a property boundary), contour boundary point mapping (precise geolocation for each point where a contour crosses a property boundary) and drainage line locations (precise path for primary and secondary water flows across a property).
Aerial contour mapping using Lidar data
Where drone-based contour mapping is not feasible, either because of land size, heavy vegetation cover, weather conditions, time constraints, distance constraints, etc., Queensland Drones can create contour maps using Lidar data captured from light aircraft.
We can deliver Lidar contour maps in most areas using existing high-definition aerial data typically less than 12 months old, so we are not constrained by distance or weather conditions. We can typically deliver 1m contour mapping with 30cm or better precision in the following areas within 2-3 business days:
- Gold Coast
- Sunshine Coast
- Moreton Bay
- Scenic Rim
- Lockyer Valley
We can also deliver 1m contour maps in parts of Toowoomba, Western Downs, Southern Downs, Somerset and Noosa regions. We are constantly adding to our available map data, so please ask us about availability of mapping data for your area.
These 1m contour maps based on topographical data are useful for most planning purposes.
Contact us for an obligation-free quote
For more information about contour mapping and topographical mapping, please contact us by phone or email.