IELTSライティング Task 1: バンド5.5 エッセイサンプル — 環境

The diagram illustrates the sequential process through which rainwater is collected from house rooftops and transformed into safe drinking water for use in an Australian town. Overall, the process comprises five distinct stages: collection, filtration, storage, chemical treatment, and finally distribution to households. Each stage plays an essential role in ensuring the water is fit for human consumption. In the first stage, rainwater falling onto sloped rooftops is directed into gutters and channelled through underground drainage pipes that connect all houses in the area. The water then flows into a water filter, which removes physical impurities such as leaves, sediment, and other particles, completing the initial purification phase. Following filtration, the cleaned water is conveyed into a large underground storage tank, where it is held until the next stage of treatment. It is subsequently pumped into a separate water treatment tank, into which chemical substances are introduced to eliminate harmful microorganisms and residual contaminants. Once the chemical treatment is complete, the fully purified drinking water is pumped through a pipe network and delivered to every household, ready for safe consumption.