Academic Writing Task 1 · process diagram

The process of collecting and treating rainwater for domestic drinking water: IELTS Writing Task 1 sample answer

An IELTS Writing Task 1 process diagram question with a Band 8 sample answer, the chart redrawn with its data, the vocabulary that lifts the report and how to write about process diagrams.
  • 189 words
  • Process diagrams
  • Academic
  • 20 minutes

The question

The diagram below shows how rainwater is collected and then treated to be used as drinking water in an Australian town.

Summarise the information by selecting and reporting the main features, and make comparisons where relevant. Write at least 150 words.

Rainwater collection and treatment process
  1. 1.Rainwater is collected from house roofs via drains
  2. 2.Water is transported through a pipe network to a central filtration system
  3. 3.Filtered water is sent to a storage tank
  4. 4.Water is moved from storage to a treatment tank
  5. 5.Chemicals are added to the water in the treatment tank
  6. 6.Treated water is distributed back to houses for drinking

Chart redrawn by BandLadder from the data in the original IELTS practice task. Many IELTS practice tasks come from the Cambridge IELTS series (Cambridge University Press & Assessment); all rights in the original tasks remain with their owners.

Model answer

Band 8 sample answer

Band 8189 words. Every figure in the answer comes from the chart above.

The provided diagram illustrates the systematic process of collecting, treating, and distributing rainwater for use as drinking water in an Australian town. Overall, the system operates as a closed loop, beginning with the collection of precipitation from residential rooftops and concluding with the delivery of treated water back to the houses.

In the initial stage, rainwater falling on the roofs of houses is captured by drains. These drains feed into a network of pipes that transport the collected water towards a central filtration unit. Once the water passes through the filter, it is directed into a large storage tank. This stage ensures that debris and larger impurities are removed before the water undergoes further processing.

Following storage, the water is transferred to a treatment tank. Here, chemicals are introduced to the water to ensure it meets safety standards for human consumption. Finally, the treated water is pumped through a distribution pipe network back to the individual houses, where it becomes available as drinking water. The entire cycle demonstrates an efficient method of water management, ensuring that natural rainfall is repurposed to meet the domestic needs of the town's residents.

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Process diagrams

How to write about process diagrams: tips and vocabulary

  • →Say how many stages there are and where the process starts and ends.
  • →Use the passive and sequencers: first, after this, once, finally.
  • →Keep every stage; a missing step costs task achievement.
  • systematic

    done according to a fixed plan or system

  • closed loop

    a system that is self-contained and circular

  • harvested

    collected or gathered for future use

  • impurities

    substances that make something dirty or impure

  • repurposed

    adapted for a different use or purpose

  • distribution

    the action of sharing or supplying something

Frequently asked questions

What should the overview say?+

The process illustrates a cyclical system where rainwater is harvested from residential roofs, filtered, stored, chemically treated, and finally distributed back to households for consumption.

How many words and how long for IELTS Writing Task 1?+

At least 150 words; 170 to 200 is the safe range. Spend about 20 minutes on it and leave 40 for Task 2, which carries twice the marks.

How is IELTS Writing Task 1 scored?+

On four criteria: task achievement, coherence and cohesion, vocabulary, and grammatical range and accuracy. A clear overview of the main features is what most separates Band 6 from Band 7 and above.

How do I describe process diagrams?+

Say how many stages there are and where the process starts and ends. Use the passive and sequencers: first, after this, once, finally. Keep every stage; a missing step costs task achievement.

Keep practising

More process diagrams

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