IELTS WRING TASK 1

The diagrams below show how houses can be protected in areas which are prone to flooding.

LINK GRAPH: https://drive.google.com/file/d/0B83RoTw6yY1AMkZsWTR4cldQSjA/view?usp=sharing

The diagrams illustrate two different methods to protect houses in the areas which are easily flooded.

Overall, the key distinction between two diagrams is the flood protection with or without the existence of a stopbank. In addition, in each case, the level of house floor is always above ground level.

The first diagram shows the way stopbank is used to prevent the river water from flooding the area. The stopbank is a mound of land locating near the berm which is always higher than the 100-year flood level. The difference between this level and the highest point of the stopbank called the ‘freeboard’. Beneath the stopbank, there is a floodgate used to adjust the water level of internal ponding. Building the house on stills is also an additional measure to deal with flooding in this case.

The second diagram illustrates how to protect houses without the help of a stopbank. There will be nothing to stop the river from flooding, so the solution is raising the floor level by putting the houses on stills. The height of stills is calculated so that the floor level in this case is 300 mm above the 100-year flood level. This measurement is also known as the ‘freeboard’.