See, understand, anticipate, act: GIS at the heart of forest management

At the Nature and Forests Department of the Public Service of Wallonia, GIS plays a central role in managing public forests. This summer's wildfires in the High Fens demonstrated just how valuable it can be in an emergency.

When wildfires swept through the High Fens in the summer of 2026, the Nature and Forests Department (DNF) of the Public Service of Wallonia (SPW) faced a situation still relatively unfamiliar in Belgium. “Like many regions in northern Europe, we have relatively little experience of managing wildfires in Wallonia,” acknowledges Boris Delfosse, Head of Cartography at the DNF.

The scale of the fires prompted the Department to seek expertise from France, particularly in forest fire prevention and protection. Fortunately, the DNF already had a crucial resource at its disposal: detailed knowledge of its forests, built up and organised over several years within its geographic information system (GIS). And the value of that information extends far beyond wildfire management.

Much like France's National Forests Office (ONF), the DNF is responsible for managing Wallonia's public forests. Its remit, however, is considerably broader, encompassing hunting, fishing and nature conservation, including the day-to-day management of nature reserves. The Department employs around 700 people, working across its central office in Namur and eight regional directorates, which are further divided into local forest management districts and sectors. Wallonia's forests are split almost equally between public and private ownership, with the DNF managing approximately 270,000 hectares of publicly owned forests and open habitats. 

With operations spread across such a large geographical area, the Department relies on a network of around 50 GIS specialists, with a dedicated cartographer in each district and regional directorate. Their primary responsibility is to maintain forest management plans. Every forest stand is mapped and described in detail, including tree species, plantation age, species mixtures, parcels and ownership. This information forms the geographic foundation for day-to-day forest management. Boris Delfosse coordinates this network from the Forest Resources Directorate in Namur.

GIS is nothing new to the DNF, but the way it is organised has changed significantly in recent years. Until 2019, mapping data was distributed across regional offices and managed using a different software environment. The Department then embarked on a major centralisation project, gradually transitioning to Esri technology, initially with ArcGIS Desktop.

With support from NSI, a major systems integrator and Esri BeLux partner, the DNF also developed Python tools to synchronise its GIS database with its longstanding operational database, automate data validation and generate the various maps required for forest management. Topology rules, attribute completeness and checks for overlapping features all help ensure data quality from the moment information is created.

The forest stand layer serves as the starting point for automatically generating different management maps, covering parcels, ownership and forest compartments.

A further milestone was reached in March 2026, when ArcGIS Pro became the Department's operational GIS environment. Data layers are now published as web services through the SPW's enterprise portal, and the DNF has introduced branch versioning.

“We have centralised all our parcel data,” explains Boris Delfosse. “Each cartographer works within their assigned geographical area, while the system allows us to manage any editing conflicts.”

The Esri platform is gradually supporting the entire workflow, from creating and updating data in ArcGIS Pro to making that information available to operational teams.

The migration also provided an opportunity to modernise the geographic reference system itself. The DNF moved from Lambert 72 to Belgian Lambert 2008, a coordinate reference system aligned with the European reference framework. This is far from a minor technical adjustment: Belgian public authorities are expected to make this transition progressively. By incorporating it directly into the geodatabase migration, the DNF can now avoid coordinate transformations that might otherwise introduce errors into its data. 

GIS is not, of course, reserved for cartographers. A central database feeds web GIS applications that make information available to the Department's 700 employees. Forest rangers and district managers can consult parcel data and combine it with other geographic layers relevant to their work. Cartographers have access to additional services, allowing them to create and print their own maps.

Making this information more widely available is an important step forward, gradually turning the forest data repository into a shared foundation for the DNF's many areas of responsibility.

This summer's fires in the High Fens brought a new dimension to years of work behind the scenes. Navigating these vast peatland landscapes is not always straightforward, even for staff who know the terrain well.

The DNF was therefore able to support firefighters with its detailed knowledge of the area and, crucially, its geographic data.

“Our role is to support the emergency services with our expertise and knowledge of the terrain,” explains Boris Delfosse. “Our forest stand maps can, for example, help identify the areas that need to be protected first. Firefighters were able to focus part of their efforts on these areas to prevent the fire from spreading.”

GIS was also used to monitor the fire's geographical progression. Fire perimeters provided by the emergency services were incorporated into the system and subsequently published on Wallonia's Geoportal.

This made it possible both to track the changing extent of the fire and to inform the public quickly about areas closed to access within the approximately 3,300-hectare operational perimeter. 

For the DNF, the crisis has above all accelerated its plans.

“We had been aiming to be ready by 2030. Nature moved faster than we had anticipated,” observes Boris Delfosse.

The Department now wants to establish a more structured approach to using ArcGIS Pro during emergencies, drawing on France's experience in forest fire prevention and protection.

Its forest data repository must be able to provide emergency responders with essential information about forest stands, roads, access routes and water sources.

Another priority is assessing how effectively forest areas can be defended against fire. Some forest tracks had already been reinforced following a major wildfire in 2011, but further improvements now need to be considered.

This detailed geographic knowledge will also be essential after the fires have been extinguished. Cartographers will need to progressively update management plans for affected areas, supporting restoration work, any necessary tree felling and the regeneration of forest stands. 

GIS is therefore becoming as important for monitoring the emergency itself as it is for guiding the forest's recovery.

Another major development is taking GIS directly into the field through the gradual deployment of ArcGIS Field Maps and Survey123.

The aim is to enable DNF staff not only to access geographic information on site, but also to collect and update data directly in the field. Centralising this information should shorten the time it takes for data to move between forest rangers, cartographers and central services.

The potential applications are extensive.

Forest management is already having to contend with the effects of climate change, from declining oak stands to outbreaks of bark beetles affecting coniferous forests. GIS helps locate affected areas, plan interventions and organise forest regeneration. 

“In the longer term, mobile tools could make it even easier to report diseased trees and share information with the teams and machinery working in the forest,” the GIS specialist explains.

Drones represent another area of development. Although their use within the DNF is still at an early stage, the High Fens fires have accelerated discussions about their potential.

Equipped with infrared sensors, drones can identify hotspots that could cause fires to reignite. More broadly, they could provide rapidly updated imagery of areas affected by fire or forest decline, without having to wait for conventional aerial orthophotography surveys.

“It's about supporting our mapping work: quickly assessing the extent of affected areas and updating our maps accordingly,” explains Boris Delfosse.

The DNF is also considering greater use of remote sensing, satellite imagery and, eventually, automated detection systems.

A potential agreement with Entente Valabre, a French organisation specialising in wildfire prevention and response, could lead to trials of sensors designed to detect fires at an earlier stage.

In just a few years, the DNF's GIS has evolved from a collection of maps managed by individual regional offices into a centralised, shared geographic data repository that is gradually becoming accessible directly in the field. 

This summer's wildfires demonstrated its value under the most demanding circumstances, while also highlighting what needs to happen next.

As climate change brings growing risks to forest landscapes, knowing the forest in detail is no longer enough. That knowledge must be kept up to date, shared across teams and made immediately available when conditions on the ground demand it.