After World War II, in the outskirts of Milan a new town, Cologno Monzese, grew out of a small borough of peasants and craftsmen, with an impressive progression of urbanization linked to a similarly relevant demographic increase; this happened while Italy was experiencing its economic "miracle" and internal migrations were also booming. Thus, the uses of soil were radically transformed: in few years new urban quarters were built on lands that had long been mainly rural. And this had a strong impact on the thick network of irrigation originating from fontanili, springs typical of this part of the Po Valley. The roofing of the ditches is here seen as an indicator to understand environmental changes. And it allows us to grasp the priorities of the municipality, faced with the necessities set by the growth: as it was repeatedly chosen to postpone the construction of a sewage system, the canals were quickly transformed into dumping for civilian and industrial waste. Moreover, through the lack of conflicts linked to this course of events we are shown how deeply culture and mentality were also changing. Physically and visually vanished, water is nevertheless a key element in the inhabitants’ collective memory.
Keywords: Irrigation, sewage systems, Cologno Monzese, urbanization, urban planning