Dear neighbors,

Following the line of transparency and technical analysis initiated with the budget review report, I want to share with you a second report, this time focused on the physical and orographic reality of our urbanization.

I am Antonio Marco, systems engineer and co-creator of this analysis. My specialty is data analysis and software simulation. Given the lack of detailed information in the official project about which specific plots will be affected and will not be able to drain by gravity due to elevation problems (being below the street level), I decided to apply Geolocation and Digital Terrain Modeling tools to provide preliminary data on this crucial issue.

Simulation Methodology

This study is not based on opinions, but on a computational model based on available public cartographic data. To prepare this preliminary report, we cross-referenced the information using:

  • Official Sources: Cartography from the Cartographic and Geological Institute of Catalonia (ICGC) and the VISSIR viewer.
  • Digital Elevation Models (DEM): We extracted the contour lines to calculate the theoretical height difference between each plot's platform and the projected street grade.
  • Cross Validation: Comparison with satellite images and drainage plans available from the GESA project (2024).

Simulation Results

25% OF PLOTS COULD REQUIRE PUMPING

The simulation estimates that approximately between 80 and 120 homes have a compromised drainage elevation with respect to the projected collector.

Technical and Economic Implications

The official project recognizes the existence of plots that will need pumping, although it does not specify the definitive list in the public report. If a home is in this situation, the conventional sewerage project implies additional considerations:

  • Installation Cost (CAPEX): Need to install a domestic pumping station, tank, and electrical adaptation.
  • Maintenance Cost (OPEX): Recurring energy expense and maintenance of an active mechanical system for life.

Conclusions and Recommendations of the Study:

  • The sources used (ICGC, IDEC, Google, IDEC–ICGC viewer) are official and valid for relief estimates, although they do not replace the precise topographical data of the executive project in situ.
  • It is strongly recommended to publish the topographical surveys and definitive connection elevations to allow independent verification by each owner.
  • Until such official data is available, this report constitutes a preliminary technical evaluation aimed at identifying risks and costs derived from the local orography, so that decision-making is as informed as possible.

Antonio Marco
Systems Engineer
Co-creator of Report Ref. IT-TOP/AVALL-2025/02