Water conservation and the common pool problem: can pricing address free-riding in residential hot water consumption?

Water is an increasingly scarce resource. It is often distributed such that consumers do not face any marginal cost of consumption, creating a common pool problem. For instance, tenants in multi-family buildings can often consume both hot and cold water at zero marginal cost. Using high-frequency data over many years, we analyze how the introduction of apartment-level metering and billing (IMB) affects hot water consumption. We find that introducing a marginal cost, reflecting the market price, decreases consumption drastically by 26%. Hence, price interventions can curb free-riding behavior and help the conservation of cheap but precious resources. Our results also show that heavy water users in the top consumption quartile account for 72% of the reduction. Moreover, cost-benefit calculations indicate that IMB for hot water is a cost-effective policy tool for reducing water and energy consumption.