Mantes-en-Yvelines (CAMY), Yvelines, France

What was done

The Communauté d'agglomération de Mantes-en-Yvelines (CAMY, France) launched a hen operation in October 2015 under its Local Waste Reduction Programme, which targeted a 7% per-capita waste cut by 2016.

59 volunteer households each received two free laying hens and a coop. The design was a monitored one-year pilot: households committed to sending the CAMY monthly tracking data — the volume of food waste fed to the hens and the number of eggs laid — for the full year.

Results (monitored monthly data)

• October 2015: 633.78 kg of food waste diverted across the 59 households (average 10.7 kg/household that month); 950 eggs laid.
• November 2015: 796.68 kg diverted (average 13.5 kg/household); 1,879 eggs laid.
• Projected over the full year: close to 18 tonnes of waste kept out of treatment across the 59 households.
• Stated aim: prove the practice is replicable and persuade the wider population to adopt hens.

What a replicating authority should know

• Monthly self-reported tracking is workable at ~60 households. CAMY got usable month-by-month diversion and egg data simply by asking participating households to report — a low-cost monitoring method.
• Expect seasonal variation. Diverted volume rose from ~10.7 to ~13.5 kg/household between October and November — month-to-month figures vary, so annual projections should not be built on a single month.
• Use the pilot explicitly as a demonstration. CAMY's stated goal was to use the 59 households as proof to convince others — the data exists to be communicated, not filed.

Honest reading

Outcome recorded as success for a monitored pilot that produced real monthly data. The ~18 t/year figure is a projection from early-months data across the 59 households, not a closed-out audited annual total — a credible estimate, but an extrapolation.