Performance of Concrete Mixed with Non-Potable Water Sources: A Compressive Strength Investigation

With growing concern over freshwater scarcity, this study explores the feasibility of using non-conventional water sources rainwater, underground water, mosque wastewater, and agricultural runoff as alternatives to potable water in concrete mixing. Five types of water were sourced locally and used in concrete mixtures designed using the ACI 211.1- 91 method with a constant water-to-cement ratio of 0.475. A total of 45 cylindrical specimens were tested for compressive strength at curing ages of 7, 14, and 28 days. The control mix using potable water achieved the highest 28-day strength (16.3 MPa), while concrete made with mosque wastewater and underground water reached 15.2 MPa and 14.7 MPa, respectively, demonstrating strong performance. Agricultural runoff showed acceptable results (14.1 MPa), suitable for non-critical applications. Rainwater, however, resulted in the lowest strength (8.5 MPa at 28 days), indicating potential issues with its chemical composition. The findings suggest that mosque wastewater and underground water are promising substitutes for structural-grade concrete, offering sustainable water reuse options in construction. This study provides practical insights for implementing alternative water strategies in water-scarce regions and underscores the need for further chemical and durability evaluations to support broader application.