Academic Writing Task 1 · process diagram

Comparison of Present and Future Water Supply Systems in Australia: 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.
  • 193 words
  • Process diagrams
  • Academic
  • 20 minutes

The question

The diagrams below show the water supply system in Australia at present and in the future.

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

Present Water Supply System
  1. 1.Dam/Storage supplies pure water to City
  2. 2.City households, factories, and shops generate waste water
  3. 3.Waste water is sent to Water Treatment Plant
  4. 4.Water Treatment Plant discharges waste water into River
  5. 5.City discharges storm water into River
Future Water Supply System
  1. 1.Dam/Storage supplies pure water to City
  2. 2.City households, factories, and shops generate waste water and storm water
  3. 3.Waste water and storm water are sent to Water Treatment Plant
  4. 4.Water Treatment Plant recycles and supplies treated water back to City

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 8193 words. Every figure in the answer comes from the chart above.

The provided diagrams illustrate the current water supply infrastructure in an Australian city and compare it with a proposed future model. Overall, the transition represents a move from a linear system, where water is used and discarded into the environment, to a closed-loop system that emphasises recycling and resource recovery.

In the present system, water is sourced from a dam or storage facility and supplied directly to the city, which comprises households, factories, and shops. Once used, the resulting waste water is transported to a treatment plant, from where it is discharged into a nearby river. Additionally, storm water from the city is released directly into the river, representing a significant loss of potential water resources.

In contrast, the future system introduces a more sustainable approach. While the initial supply from the dam remains the same, the management of output is fundamentally altered. Both waste water and storm water are redirected from the city to the water treatment plant. Crucially, instead of discharging this water into the river, the plant treats and recycles it, supplying it back to the city. This circular process significantly reduces reliance on external storage and minimises environmental impact.

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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.
  • linear

    a system where resources are used and discarded

  • closed-loop

    a system where resources are recycled and reused

  • infrastructure

    the basic physical systems of a city's operation

  • redirected

    changed the path or destination of something

  • minimises

    reduces something to the smallest possible amount

  • fundamental

    forming a necessary base or core of something

Frequently asked questions

What should the overview say?+

The diagrams illustrate a shift from a linear disposal-based water system to a circular, sustainable model that prioritises water recycling.

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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