Project Title

Industrial and Environmental Risk Clusters in the Gironde Region

This project examines the spatial distribution and concentration of industrial and environmental risks in the Gironde region. The analysis focuses on regulated industrial facilities (ICPE), pollutant-emitting installations (IREP), hazardous-material pipelines, and former industrial sites to identify zones of cumulative environmental risk.

Research Goals

The objectives of this research are to:

Research Questions

The project addresses the following four research questions:

  1. Spatial Distribution
    How are industrial and environmental risk facilities (ICPE, IREP, and pipelines) distributed across the Gironde region?

  2. Clustering and Proximity
    Do pollutant-emitting facilities tend to cluster spatially within existing industrial zones and infrastructure corridors?

  3. Historical Overlap
    Is there a spatial overlap between current pollutant-emitting sites and former industrial activity?

  4. Risk Density and Discharges
    Do communes with higher densities of ICPE and IREP facilities also report greater environmental discharges?

Research Data

This project relies exclusively on publicly available open-data sources related to industrial risk and environmental infrastructure in the Bordeaux–Gironde region.

1. Former Industrial Sites (CASIAS)

Geolocated dataset of former or potentially contaminated industrial sites.
Source: Bordeaux Métropole Open Data
https://datahub.bordeaux-metropole.fr/

2. Hazardous-Material Pipelines

Spatial dataset describing underground and above-ground pipelines transporting hazardous fluids.
Source: Bordeaux Métropole Open Data
https://datahub.bordeaux-metropole.fr/

3. Pollutant-Emitting Industrial Facilities (ICPE + IREP)

National datasets listing regulated industrial installations reporting emissions to air, water, or soil.
Source: Géorisques (France)
https://www.georisques.gouv.fr/

4. Administrative Boundaries

Departmental and communal boundaries for spatial aggregation and visualisation.
Source: GADM
https://geodata.ucdavis.edu/gadm/

Datasets Used

  • Former industrial sites (historical activity)
  • Hazardous-material pipelines (linear infrastructure)
  • ICPE facilities (regulated industrial installations)
  • IREP facilities (pollutant-emitting installations)

Data Processing and Methods

The analysis includes:

Data Visualisation Overview

The results are presented through three complementary visualisations:

  1. Base Map of Industrial Risks
    Showing ICPE sites, pollutant-emitting facilities, former industrial sites, and pipelines.

  2. Industrial Activity Hotspot Map
    A kernel density map illustrating cumulative industrial presence.

  3. Density vs Discharge Scatter Plot
    Relating ICPE + IREP facility density to reported environmental discharges at the commune level.

Each visualisation supports a specific research question.

Question 1

How are industrial and environmental risk facilities distributed across the Gironde region?

Industrial risk facilities in Gironde exhibit a strongly clustered spatial pattern rather than a uniform distribution.

The base map reveals that the Bordeaux metropolitan area constitutes the dominant industrial core of the region. ICPE sites, pollutant-emitting installations, former industrial locations, and pipelines are densely concentrated in and around Bordeaux, reflecting its historical role as a major industrial and logistical hub.

Outside the metropolitan core, industrial facilities become increasingly sparse and fragmented. Rural and peripheral communes contain fewer sites and contribute less to overall regional risk. Pipelines follow a predominantly north–south alignment and intersect the most industrialised zones, reinforcing existing spatial concentrations rather than creating new ones.

Overall, the spatial distribution highlights a clear core–periphery structure driven by historical land use, infrastructure availability, and industrial path dependency.

Question 2

Do pollutant-emitting facilities cluster spatially within industrial corridors?

The kernel density hotspot map provides clear evidence of industrial clustering. Using a 1 km KDE radius, cumulative industrial presence peaks sharply in the Bordeaux metropolitan area.

Hotspot intensity declines progressively with distance from the urban core, forming a pronounced spatial gradient. Secondary hotspots are visible along major transport and estuarine corridors, indicating industrial expansion along infrastructure axes rather than random dispersion.

The clustering pattern suggests intentional co-location of industrial activities, where firms benefit from shared infrastructure, transport access, and zoning compatibility. This spatial concentration increases the likelihood of cumulative environmental impacts in hotspot areas.

Question 3

Is there a spatial overlap between current pollutant-emitting sites and former industrial activity?

Overlay analysis shows substantial spatial overlap between current pollutant-emitting installations and former industrial sites.

This overlap is most pronounced in the Bordeaux metropolitan area, where historical industrial land use has persisted through continued operation or redevelopment. Areas with high historical industrial density also exhibit high present-day industrial intensity.

Peripheral former industrial sites are more dispersed and generally associated with lower current emission densities, suggesting partial industrial decline or land-use transition. The observed pattern indicates strong continuity of industrial land use over time.

From a risk perspective, this overlap implies cumulative and layered environmental pressures, where historical contamination may coexist with ongoing emissions.

Question 4

Do communes with higher facility density report higher environmental discharges?

The scatter plot relates ICPE + IREP facility density per km² to total reported environmental discharges, both expressed on log₁₀ scales.

A clear positive relationship is observed: communes with higher facility densities generally report higher total emissions. Very high-density communes cluster in the upper-right portion of the plot, indicating both high industrial concentration and high environmental burden.

However, variability around the regression line shows that facility density alone does not fully explain emission levels. Some moderate- density communes exhibit disproportionately high discharges, reflecting the presence of large or highly polluting facilities. Conversely, some high-density communes report relatively lower emissions, possibly due to cleaner technologies or sectoral differences.

Overall, environmental pressure in Gironde is shaped by both the number of facilities and their emission intensity.

Integrated Interpretation

Taken together, the three visualisations demonstrate that industrial and environmental risk in Gironde is spatially concentrated, historically structured, and infrastructure-dependent.

Risk is greatest where industrial density, legacy land use, and emission intensity intersect, most notably in the Bordeaux metropolitan area. The findings emphasise that environmental exposure is cumulative and place-based rather than evenly distributed, supporting the need for targeted, spatially differentiated environmental risk management.