Stage 1 of the journey (see the site home page): the starting point.
The annual waste report of the Pays Voironnais contains a double page devoted to the territory's flows. It is a process diagram: every link has the same thickness and the tonnages are written alongside, so nothing shows that one flow weighs ten times another. It sits on pages 16-17 of the 2024 annual waste report (in French).
This diagram is the demonstration that opened the conversation: the same story, carried by a Sankey diagram where the width of each flow is proportional to its tonnage.
The full chain of the service, unfolded in finer detail than on the other pages — 78 nodes: household and similar waste, split between household and similar refuse (plastic and metal packaging, paper, household and trade cardboard, glass, food waste, residual waste) and occasional waste (furniture, WEEE, rubble, wood, plasterboard, green waste, bulky waste, scrap metal); the collection modes — kerbside collection flow by flow, bring banks, civic amenity sites, including those in the north of the territory taken separately; sorting, transfer and transit — the composting platform and transfer dock of the La Buisse ecological site, and the Athanor sorting centre; and treatment, with sorting and screening residues made visible at each step.
The level selector folds and unfolds each of these stages, from the most synthetic view down to the detail by material.
This page is a demonstration, predating any commission. It shows what a Sankey adds to an existing process diagram; it did not go through the tonnage validation work carried out later on the other two pages. For the department's published figures, refer to the authority's annual waste report.
Diagram: TerriFlux, with OpenSankey. Public data from the waste department of the Communauté d'agglomération du Pays Voironnais.