Engineers Without Borders

Last week a group of UNSW students who are part of the Engineers Without Borders initiative worked with our Year 8 Science classes on solving a problem that related to an issue faced by people living in poorer regions of our planet.

The challenge involved building a house that would float on a lake. The type of scenario faced by people living in The Tonle Sap in Cambodia.

The Tonle Sap is a large body of freshwater in central Cambodia that is home to unique wildlife.  Over a million people rely on the lake to survive. Many Cambodians rely on the river’s fish for food and a source of income, and the banks of the water systems are used for rice fields.

Several rivers flow into the Tonle Sap. The primary river is the Mekong River which carriers vital nutrients into the lake before flowing into the ocean.

During the dry season the Tonle Sap occupies an area of approximately 3,000 square kilometres at an average depth of 1m, but during the wet season the flow in the Mekong River and the other rivers increases greatly. This causes the lake to become 5 to 6 times larger than it is in the dry season, and deepens to 10m or more.

During the wet season the lake area can occupy 32% of the entire country. This flooding makes it hard to build traditional houses on land near the lake. Some people do live in houses on the banks of the lake during the dry season, but when the flooding occurs they need to abandon their houses for higher ground before they become submerged.

After an introduction to the challenge by the engineering students they were given a few basic items to use in their construction. The aim was to build a floating house that can hold the greatest number of marbles. Each team had a budget of 5 units.

Each of the following things cost 1 unit:

  • 1 X cup (foam) OR 1 X balloon or 1 X A5 cardboard
  • 4 X straws OR 4 X paddle pop sticks OR 4 X rubber bands
  • 30cm sticky tape OR 30cm aluminium foil

It was wonderful to see the creative energy produced by teams as they worked together to create a construction that would prove to be the most successful in the test at the end of the session. This was a wonderful authentic STEM project and one we hope to provide our students with again in the near future.