We’ve nearly finished an earthbag water tank with narrow tubes that cost $200 in materials. Plastic tanks this size retail for around $1,350 in Vanuatu, so this design costs far less than the main competing product. It won’t blow away in a hurricane, break down from UV rays or taint the water with plastic chemicals. Our water tank includes a domed ferrocement top that’s exceptionally strong. It can be built in 2-3 days by four workers with minimal skill, although plastering skill is very helpful. There’s a huge water shortage on the islands here in Vanuatu, as well as many other places. Those who learn this method could make a lot of money selling water tanks since demand is high and cost of labor is cheap.