Bags of water
A waterbag is a flexible container system for freshwater transport. The Refresh project consortium chose to test their water bag prototype in Crete. The technology is not new, but the team have developed a new approach.
Engineer Samuele Ambrosetti explained: “You can see here a water bag made from supple PVC, which is used for transporting fresh water by sea. It’s used to supply fresh drinking water to islands and coastal communities without a regular supply of fresh water – in summer for instance.”
The General Manager of Ziplast, Gianfranco Germani, said: “For this project we had to develop a new zip that is strong enough to resist the lateral pressure, that is water-proof, and that can resist the hydraulic pressure that can build up in the water bag.”
The zip is one of the key elements of this new generation water bag. The container is made up of several modules which means its capacity can be adjusted according to demand. The different sections are also designed to form a compact shape while under tow.
“This is a medium-sized prototype,” Ambrosetti went on. “It can contain 200 cubic metres of water, which is already considerable. But we think that on a commercial scale our water bag could contain ten times that – in other words, 2,000 cubic metres.”
This type of water storage and transport is also cheap to run. The waterbag is peppered with sensors to warn of any deformation of the container while underway at sea.
The tests conducted in Crete have borne fruit. Once empty, the modular waterbag is easier to disinfect and to transport.
Germani explained: “Lastly, dismantling the waterbag has proved simple, thanks to the way the teeth of the zip undo. That is the removal of the locking mechanism in the middle of the zip. Internal pressure is enough – no need for human intervention.”