Promoting Water Efficiency in a Municipal Market Building: A Case Study

Abstract

This study aimed to determine the water demand of a Municipal Market building to propose water use efficiency measures. The flushing cisterns have the highest water consumption (63.15%), followed by washbasins, restaurant and coffee shop taps, and hairdresser’s showerhead (31.64%). Therefore, the implementation of two main categories of solutions: reducing water consumption through the adoption of efficient devices and installing a rainwater harvesting system (RWHS) when drinking water quality is not required, was evaluated. These solutions were organized in four distinct scenarios: (1) Flushing cistern replacement by dual-flush ones; (2) washbasins, restaurant, coffee shop taps, and hairdresser showerhead replacement; (3) scenario 1 combined to a RWHS for recharging the replaced flushing cisterns and (4) combining scenarios 3 and 4. Under scenarios 1, 2, 3, and 4, the expected water consumption reduction was 28.36%, 17.06%, 57.36%, and 74.41%, respectively. As a result, the annual water bill reduction was €3835.81 (scenario 1), €2307.07 (scenario 2), €7757.65 (scenario 3), and €10,064.73 (scenario 4). Furthermore, to ensure the harvested rainwater attains the required standard for recharge flushing cisterns, it is advisable to dispose of the first-flush rainwater collected after a long dry period.