Bare-Earth Mapping

Accurate Terrain Models Beneath Vegetation

At LiDAR Drone Australia, we provide high-resolution bare-earth mapping using drone-mounted LiDAR to reveal the true shape of the ground beneath vegetation, tree canopy and other surface features.

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For projects where conventional aerial imagery cannot clearly see the terrain, LiDAR offers a powerful alternative. By recording multiple laser returns through gaps in vegetation, we can identify and classify ground points to create an accurate representation of the underlying land surface.

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The result is a detailed terrain dataset that can support surveying, engineering, civil design, environmental assessment, drainage analysis, infrastructure planning and land management.

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See the Ground, Not Just the Canopy

Traditional aerial photography and photogrammetry generally record what can be seen from above. In heavily vegetated areas, this often means the visible surface is the tops of trees, shrubs and ground cover rather than the actual terrain.

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LiDAR works differently.

A LiDAR sensor sends thousands of laser pulses toward the ground every second. Many of these pulses produce multiple returns as they interact with leaves, branches, understorey and the ground below.

Where sufficient openings exist within the vegetation, some laser pulses reach the ground surface. These ground returns can then be identified during processing and separated from vegetation and other objects.

This allows us to develop a bare-earth terrain model that represents the land beneath the vegetation as accurately as the available LiDAR returns allow.

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What Is Bare-Earth Mapping?

Bare-earth mapping is the process of removing above-ground features from a LiDAR point cloud to produce a model of the underlying terrain.

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Features that may be filtered or classified separately include:

• Trees and vegetation

• Shrubs and understorey

• Buildings

• Vehicles

• Temporary site features

• Other above-ground objects

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The remaining ground-classified points are used to create a continuous terrain surface.

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This terrain information can then be converted into a range of useful deliverables including:

• Digital Terrain Models (DTM)

• Digital Surface Models (DSM)

• Contours

• Triangulated Irregular Networks (TINs)

• Ground-classified LAS / LAZ point clouds

• Hillshade models

• Cross-sections and profiles

• CAD-ready terrain data

• GIS-compatible datasets

• 3D terrain models

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Digital Terrain Models — DTM

A Digital Terrain Model represents the underlying ground surface after vegetation, buildings and other non-ground features have been removed from the dataset.

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DTMs are commonly used for:

• Engineering design

• Drainage modelling

• Flood studies

• Road and infrastructure planning

• Earthworks assessment

• Catchment analysis

• Environmental investigations

• Access planning

• Slope and terrain analysis

• Preliminary design and feasibility studies

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In vegetated environments, a LiDAR-derived DTM can provide significantly more useful terrain information than a surface model produced from aerial photography alone.

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Digital Surface Models — DSM

A Digital Surface Model represents the uppermost surface detected by the LiDAR system.

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This can include:

• Tree canopy

• Vegetation

• Buildings

• Structures

• Ground surfaces

• Other visible features

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By comparing a DSM with a bare-earth DTM, valuable information can be obtained about the height and structure of objects above the ground.

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This is useful for applications such as vegetation height analysis, canopy assessment, infrastructure studies and environmental monitoring.

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Contour Generation

Once the terrain surface has been created, we can generate contours at intervals appropriate to the project and the quality of the source data.

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Contours can assist with:

• Site planning

• Civil design

• Drainage assessment

• Road alignment

• Development investigations

• Landscape design

• Environmental planning

• Earthworks

• Access and construction planning

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Contour intervals should always be selected with consideration for the accuracy, terrain, vegetation and intended use of the data. Our focus is on supplying realistic, project-appropriate outputs rather than overstating what the dataset can support.

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Triangulated Irregular Networks — TINs

A TIN, or Triangulated Irregular Network, is a three-dimensional representation of the terrain created by connecting elevation points into a network of triangles.

TIN surfaces are widely used in engineering, surveying and civil design software because they provide an efficient way to model changing terrain.

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LiDAR-derived TINs can support:

• Civil design

• Road and drainage design

• Cut-and-fill calculations

• Earthworks modelling

• Surface comparison

• Long sections and cross-sections

• 3D visualisation

• Engineering assessment

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Where required, terrain models can be prepared for integration into common CAD, GIS and engineering workflows.

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Bare-Earth Mapping in Dense Vegetation

One of the primary reasons clients choose LiDAR is its ability to obtain ground information in areas where aerial photography alone may be ineffective.

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These environments can include:

• Dense bushland

• Forested areas

• Riparian corridors

• Overgrown development sites

• Road reserves

• Powerline corridors

• Rail corridors

• Creek lines and drainage reserves

• Steep escarpments

• Rural properties

• Environmentally sensitive areas

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However, it is important to understand that LiDAR does not see through vegetation in the same way that X-ray imaging passes through an object.

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The laser pulses must still find openings within the canopy and vegetation structure to reach the ground.

For this reason, vegetation density, canopy type, understorey, flight altitude, flight speed, scan geometry and point density can all influence the number of usable ground returns.

We take these factors into account when planning each survey.

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High-Density LiDAR for Better Ground Definition

When bare-earth terrain is an important project requirement, survey planning becomes critical.

​We can adjust flight parameters to increase the opportunity for ground returns by considering factors such as:

• Flight altitude

• Aircraft speed

• Flight-line spacing

• LiDAR scan settings

• Multiple flight directions

• Terrain variation

• Vegetation density

• Required point density

• Survey extent

• Desired final deliverables

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High-density capture can provide more opportunities for the LiDAR system to record ground returns, particularly in complex vegetation.

The objective is not simply to collect the largest possible point cloud. It is to capture the right data for the required terrain model.

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Applications for Bare-Earth LiDAR

Bare-earth mapping can be valuable across a wide range of industries and project types.

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Engineering and Civil Works

Detailed terrain information can support preliminary design, drainage, access roads, earthworks, subdivisions and infrastructure planning.

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Roads and Transport Infrastructure

LiDAR can assist with mapping road corridors, embankments, cuttings, surrounding terrain and vegetated areas adjacent to existing infrastructure.

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Environmental Projects

Bare-earth models can help identify drainage patterns, creek lines, erosion features, landscape form and terrain beneath vegetation.

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Flood and Drainage Studies

Accurate terrain information is an important input for hydrological and hydraulic modelling, catchment investigations and drainage planning.

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Powerline and Utility Corridors

LiDAR can provide terrain and vegetation information across long linear corridors and difficult-access areas.

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Property and Development Investigations

For undeveloped or heavily vegetated sites, LiDAR can provide a clearer understanding of the terrain before detailed planning and design work begins.

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Forestry and Land Management

Bare-earth terrain data can assist with access planning, slope analysis, drainage, rehabilitation and environmental management.

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Detailed Data Without Walking Every Metre of the Site

Many sites that require bare-earth mapping are also difficult to access.

Steep slopes, thick vegetation, waterways, unstable ground and large survey areas can make traditional ground-based data collection time-consuming and potentially hazardous.

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Drone LiDAR allows large areas to be captured from the air while reducing the need for personnel to physically access every part of the site.

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Ground surveying may still be required for control, verification or specific project requirements, but LiDAR can significantly increase the amount of terrain information available across the overall project area.

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Our Bare-Earth Mapping Deliverables

Depending on your project requirements, LiDAR Drone Australia can provide:​

• Raw LiDAR point clouds

• Classified LiDAR point clouds

• Ground-only point clouds

• LAS and LAZ files

• Digital Terrain Models

• Digital Surface Models

• Contours

• TIN surfaces

• Hillshade models

• Elevation rasters

• Cross-sections

• Longitudinal profiles

• 3D terrain models

• CAD-compatible files

• GIS-compatible files

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We can also coordinate deliverables with your surveyor, engineer, environmental consultant, designer or GIS team so the information is supplied in a practical format for the next stage of the project.

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Practical and Professional Approach

At LiDAR Drone Australia, we believe good LiDAR work starts with understanding what the client is trying to achieve.

Every site is different.

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A lightly vegetated construction site requires a different approach from dense bushland, a steep escarpment or a long infrastructure corridor.

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Before we fly, we consider the terrain, vegetation, project purpose, required outputs and the level of detail needed. We then plan the capture methodology around those requirements.

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Our goal is to provide reliable, useful and well-processed terrain information, while being clear about the capabilities and limitations of the technology.

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Discuss Your Bare-Earth Mapping Project

If you need to understand the terrain beneath vegetation, LiDAR Drone Australia can help assess whether drone LiDAR is suitable for your project.

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Send us your:

• Site address or location

• KML or KMZ project boundary

• Approximate survey area

• Required deliverables

• Intended use of the data

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We can review the project area and discuss the most appropriate LiDAR capture and processing approach.

LiDAR Drone Australia

High-density LiDAR capture for accurate bare-earth terrain mapping.

DTM. DSM. Contours. TINs.

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Classified Point Clouds. Practical terrain data for real-world projects.