Joint with Germà Bel, IREA working paper.
Municipalities increasingly cooperate with one another to improve their public services. We estimate the causal effect of Inter-Municipal Cooperation (IMC) on the environmental performance of waste collection in Catalonia. Using a difference-in-differences framework and conditioning parallel trends on drivers of selection into treatment, we find that joining an IMC causes a decrease in unsorted waste. The effect is driven by municipalities joining IMCs in 2016 or later, where joining IMC decreases non-separated waste by more than 13%. This results in an increase in the waste separation rate of 4.9 percentage points or 13% compared to the 2014 baseline. We show that IMCs caused this improvement by adoption of the Door-to-Door waste collection policy. Thus, they aimed to reduce local environmental hazards from landfills. IMCs have taken on their environmentally beneficial role only over time, possibly because a general increase in environmental issue salience made hazards from landfills tangible enough to warrant action..
Find the complete working paper here.