Cement Sand Mortar with Alternative Mixing Waters: Comparative Workability and Strength Analysis

Freshwater scarcity and construction-related environmental impacts have increased interest in alternative water sources for cement-based materials. This study evaluated sanitary water, seawater, river water, and canal water as partial and full replacements for potable water in cement–sand mortar. Seventeen mixes were prepared at 25%, 50%, 75%, and 100% replacement levels and tested for workability, water absorption, compressive strength, flexural strength, and failure behavior. Results showed that performance depended on both water type and replacement level. Most non-potable waters improved workability, with river water showing the highest flow response. However, hardened properties varied considerably. Sanitary water generally reduced strength, while seawater and river water showed mixed but promising results. Canal water performed best overall, especially at 75% and 100% replacement, where it produced the lowest water absorption and the highest compressive and flexural strengths.