One Drone Survey, Multiple Uses: From Drainage Planning to Landscape Design

Drone mapping is often commissioned to solve one particular problem. However, one of its biggest advantages is that the data collected during a single flight can be processed into several different outputs—each supporting a different stage of a project.

A recent mapping project carried out by Dolphin Media is a perfect example.

The original requirement: understanding the drainage

The initial purpose of the survey was to help investigate drainage around a lake and the surrounding field.

Although changes in ground level can sometimes be seen from site photographs or during a walkover, subtle slopes and low points are much harder to identify accurately from ground level. These small variations can have a significant effect on where rainwater collects, how it moves across the site and where drainage improvements may be needed.

We mapped the area by drone, capturing a large number of overlapping, accurately positioned aerial images. These were then processed to create a detailed digital representation of the site.

From this single flight, we were able to produce several useful outputs, including:

• A high-resolution aerial orthomosaic
• A digital elevation model
• A colour-coded elevation map
• Contour mapping
• Hillshade and slope visualisations
• A three-dimensional model of the field and surrounding terrain

Each output presented the same site data in a different way.

The contour and elevation maps made it easier to understand how the land rises and falls, while the slope and hillshade outputs helped reveal the shape of the ground more clearly. Together, they provided useful information for considering surface-water movement and potential drainage routes around the lake.

The same contour map, used for landscape design

Since completing the survey, we have learned that the contour map is also being used to support the wider landscape design of the site.

This demonstrates the wider value of collecting good-quality mapping data. Contours are useful for far more than drainage. They can help landscape designers understand how proposed features will relate to the existing land, assess changes in level and plan paths, planting areas, terraces, access routes and other features around the natural topography.

Rather than starting again with another survey, the designer already has a clear and measurable representation of the site’s existing levels.

Turning the 3D model into an amphitheatre concept

The three-dimensional model created from the drone survey has also found an additional use.

The landowner is planning to provide the model to a designer, who can use it as the basis for mocking up a proposed amphitheatre at the top of the field.

Because the model represents the existing shape and gradient of the land, the proposed design can be explored within the context of the real site. This should make it easier to consider the amphitheatre’s position, orientation, scale and relationship with the surrounding landscape before any physical work begins.

It also gives the client and designer a much clearer way to communicate ideas. Instead of relying solely on flat plans or photographs, they can visualise how a proposed feature might sit within the terrain.

Capturing the site once, creating value several times

What began as a drainage mapping project has therefore produced information that can support at least three separate areas of work:

1. Understanding levels and surface-water drainage around the lake
2. Supporting the wider landscape design
3. Providing a 3D base model for a proposed amphitheatre

The original drone flight does not need to be repeated for each application. The same underlying dataset can be processed, presented and shared in different formats depending on who needs to use it.

This is particularly valuable on larger or more complex sites, where architects, drainage specialists, landscape designers, contractors and landowners may all need different information about the same piece of land.

More than an aerial photograph

Aerial photography remains a useful part of a drone survey, but it is only one possible output.

With suitable flight planning and processing, drone mapping can create a reusable digital record of a site. It can help answer the immediate question while also supporting design discussions, planning, measurements, visualisations and future comparisons.

This project began with a need to better understand drainage. It has since developed into a useful foundation for landscaping and the visualisation of an entirely new feature within the field.

That is where drone mapping offers its greatest value: capture the site once, then use the data in multiple ways.

If you have a site where levels, drainage, landscaping or future development need to be better understood, Dolphin Media can create accurate aerial maps, terrain models, contour plans and 3D site visualisations tailored to the project.