Amsterdam University of Applied Sciences

Students work on water supply in Bangladesh

20 Jun 2014 00:00 | Communication

Three AUAS Civil Engineering students plan to improve the water supply in a slum area in Bangladesh. On behalf of development organisation Simavi and water supply company Vitens, the students travelled to Dhaka in May to see the situation for themselves. Although the living conditions came as a shock to the students, the conditions also inspired them to come up with solutions to make the drinking water supply and the waste water cleaner.

Students Theo, Dennis and Hylkje (Civil Engineering) spent three weeks in the slums of Jheelpar in Dhaka, to study the water supply as a final thesis assignment. Dennis studied the system for drinking water, which is tapped illegally. Dennis explains: “Homeowners rent the corrugated iron shacks to families in the slums. They obtain drinking water by secretly drilling holes in the water pipes and tapping it off with hoses. These plastic hoses run right through piles of waste and excrement, so the small amount of water that comes out is no longer clean.”

Collecting rainwater

Dennis came up with the alternative of collecting rainwater. With a rainy season lasting seven months, there is plenty of rainwater in Bangladesh. Dennis presented two versions. The first is a cheap system: bamboo pipes on the roof drain the water into the plastic bottles of a water cooler. A ceramic filter is used to purify the water. The filter has a layer of baked clay. Although it sounds simple, it is a tried and tested method of purifying water – most of the bacteria remain in the clay.

There is also a more expensive version: a PVC system (rooftop harvesting) collects the water from multiple roofs. The rainwater flows into a concrete tank with a sand filter. If it rains hard, the excess water flows into the ground, right through the 25 metre clay layer via a deep tube. Groundwater lowering is a major problem in Bangladesh.

Hanging toilets

Dennis’ fellow student Theo took on another pressing issue: wastewater. “The toilets there are small huts suspended above the lake. All of the ‘wastewater’ drops right into the lake, as a result of which it is highly polluted,” explains Theo. He has been charged with finding a solution to the wastewater problem, but it has to be realistic for the desperately poor inhabitants of the slums.

Peepoo

Theo presented two solutions. For the short term he recommends Peepoo bags – “the name speaks for itself” – which are then brought to a central depository. The bags are made of biodegradable material and can be used as fertiliser within a few weeks. However, because the bags are too expensive for the inhabitants, an investment by Dutch or local businesses is required. Theo’s long-term suggestion is the installation of a septic tank beneath the toilets. An additional problem is that the streets in the slums are too narrow for lorries. Therefore, Theo recommends having the tank emptied by a boat each year.

Useful culture shock

Lecturer Rutger van Hogezand of the Water Management programme thinks the students’ trip to Bangladesh was very useful: “This is a great lesson – experience teaches you so much more than simply learning from books. The students witnessed the severe living conditions with their own eyes, and now realise the importance of drinking water and clean toilets. They now truly understand that it is a basic necessity of life. That’s why I do it.”

Vitens/Evitens International has investigated a number of possibilities of dredging a polluted canal beside the slums. On behalf of VEI, student Hylkje is studying how the water quality of the canal beside the slums can be improved. She is also studying how the dredged materials can be processed and reused. Hylkje will present the results of her research after the summer.