Determination of drinking water consumption during the construction of houses in a semi-desert area of Chile

ABSTRACT In recent years, water scarcity in northern Chile has increased markedly, leading to an over exploitation of groundwater aquifers. In the construction sector, water is used in large quantities throughout the different activities of the construction projects, this fact makes essential to quantify the water consumption in order to know the real demand for water, and thus to have a clear and precise vision about the volumes of this resource which are used in the different activities of a construction project. In this study, the water consumption coefficients in relation to the different items corresponding to the construction of 219 homes and 2 multipurpose rooms were determined. For this purpose, the theoretical results of water demand obtained by means of calculations of the project, were compared with the results obtained in the real consumption of water in-situ. Results obtained for theoretical and real consumption of the tasks showed that the theoretical water volume to be used in the work was 10,946 m3, this value differs with the real volume of 16,283 m3 of water used in the project, i.e., it was used an additional volume of 5,337 m3. The latter implies an increase of 48.8 % in water consumption, if compared to the theoretical water volume. The main water consuming activities were the following: soil compaction, irrigation to control particles in suspension, curing of concretes and mortars, worker camp, manufacture of concrete and mortars. Within these activities, the one that presented a higher than expected consumption was the irrigation for the control of suspended particles, whose theoretical value was 3,936,000 m3 and the real consumption was 6,010,000 m3, that is 53% higher than the provided. Considering the results obtained in this study, it is possible to estimate that in the construction sector there is higher water consumption, in comparison with the theoretical demand. In this sense, it is necessary to develop detailed studies based in the actual water consumption that guarantee the sustainability of this resource in arid zones.

摘要 近年来，智利北部水资源短缺问题显著加剧，致使地下水含水层遭到过度开采。在建筑行业中，各类建筑项目的全流程均需消耗大量水资源，这一现状使得量化用水消耗量、掌握真实用水需求，进而清晰精准地把握建筑项目各环节的水资源使用体量，成为必要之举。本研究针对219套住宅及2间多功能用房的建设项目，确定了对应各分项工程的用水系数。为此，将通过项目计算得到的理论需水量结果，与现场实际用水监测结果进行对比分析。任务的理论与实际用水量测算结果显示：本工程理论总需水量为10946立方米，而项目实际总用水量达16283立方米，二者相差5337立方米，即实际用水量较理论值增加了48.8%。主要用水环节包括：土壤压实作业、悬浮颗粒物控制洒水作业、混凝土与砂浆养护、工人营地用水，以及混凝土和砂浆拌合制备。其中，实际用水量超出预期幅度最大的环节为悬浮颗粒物控制洒水作业，其理论值为3936000立方米，实际消耗量达6010000立方米，较理论值高出53%。基于本研究结果可推断，建筑行业的实际用水量高于理论需水量。据此，有必要基于实际用水情况开展精细化研究，以保障干旱地区水资源的可持续利用。