Opportunities for Reducing Water Consumption in Concrete Production: The Panama Canal Expansion Case Study

Concrete is the most used material in the world after water. The annual global production of more than 30 billion tons is expected to keep growing at least until 2050. Even though the production of concrete has important environmental impacts, we cannot prevent its use as it is needed for basic housing and infrastructure. Therefore, we need be more efficient during its production. The water footprint is a tool that allows measuring the water use in a product’s life cycle, its potential environmental impacts and helps identifying opportunities for water use reduction. This methodology is in compliant with the ISO standards 14046, 14040 and 14044. The aim of this paper is to identify water reduction opportunities in concrete production. To do so, the concept of water footprint is introduced and applied to a concrete production case study: the Panama Canal Expansion. This study is done from cradle to gate, i.e. from the extraction and production of raw materials to the delivery of the concrete. The water use for the production of 8 concrete mix designs for the Panama Canal expansion is estimated. Approximately, 375000 m³ of water were used only for mixing the concrete. To reduce water consumption in the life cycle of any product, the first thing to do is to gather information on the amount of water that is used and where it is used. The results are relevant for the industry to focus in water reduction opportunities to decrease the pressure in water resources.

Keywords: Cementitious materials. Water use. Water footprint. Life cycle assessment. Sustainable construction.