Montchoisi - a mixed-use neighbourhood in Lausanne with 3'766 residents, cafés, essential services and generous green spaces - already separates waste on an established schedule, yet its most abundant streams remain bio-waste, green waste and wood off-cuts. Kitchen scraps from households, cafés, and supermarkets are still routed to TRIDEL’s energy-from-waste plant; weekly bundles of garden trimmings and seasonal tree prunings leave the district as “green waste”; and reclaimable timber from parks and renovations is dropped at mobile or fixed déchèteries for eventual incineration or recycling. By tracing these three waste flows, we uncovered a missing, decentralised loop that could return nutrients and biomass directly to the neighbourhood, while paper, plastics and metals already follow efficient city-wide circuits.
Our proposal, “From Waste to Harvest,” turns the area into a continuous green corridor. Each of Montchoisi’s three main roundabouts is re-landscaped as a pocket park where compact, odour-sealed compost modules process local bio-waste and shredded wood chips. Therefore, connecting streets becomes a “sponge ribbon” of lane- narrowings, raised crossings and permeable paving; traffic calms below 30 km/h while bioswales capture storm-water and feed roadside planters. At the district’s primary and secondary schools, plug-in compost drums and raised beds give pupils direct responsibility and hands-on engagement with community gardening. Guided by the participatory ethos of the EnVie Montchoisi Association, seasonal workshops, seed exchanges and community harvest days weave these physical interventions into neighbourhood life, turning waste management, road safety and environmental education into one visible act of shared urban consciousness.