A Lightweight, Deployable Water Purifier – Captain Dael Liddicoat
I have an idea for producing high-quality drinking water at very short notice in support of soldiers engaging in disaster relief efforts. It will significantly reduce the need for ongoing resupply and the extremely high cost associated with moving bulk water. The solution is a lightweight water purification unit.
Contaminated water supply during natural disasters is a serious concern that quickly falls to assist organisations such as the Australian Defence Force (ADF) to combat. Deployment of the existing Reverse-Osmosis Water Purification Units (ROWPU) takes time, and does not solve the distribution problem which can often lead to increased tasking for rotary wing and surface assets. My idea is to decentralise water production through the distribution of a number of my lightweight water purifiers, allowing purification of water at the point of need. This would significantly reduce the continued logistics burden of moving water, reduce the likelihood of contaminated water being distributed and allow for extensive and robust planning to be conducted to optimise the positioning of long term water production plants such as the ROWPU.
The NQLD flood assist mission saw several communities isolated and not accessible by land. The only solution was aerial delivery of bottled water. During this period shopping centres were quickly emptied out and water needed to be brought into the region by C17 and then redistributed using MRH90. At this time 5 AVN had a functioning water purifier designed for the production of ‘technical’ grade water. The need for a similar device that could be easily and quickly deployed and would fill the gap between the 10,000L / day ROWPU and delivery of bottled water became very apparent. Imagine the alternative to delivering tonnes of bulk water every day as a once off delivery of 2-3 small, solar powered purifier units capable of producing up to 1000L of clean drinking water each day. No resupply, one-time delivery, and self-sustaining communities at extremely short notice.
The device will produce sufficient water to sustain up to 250 people at 4L/day or equivalent to two military companies. The obvious limitation is the requirement for an accessible water source. However, with this system the water source can be a dam or creek and there is no requirement for a large support organisation in location to run and maintain the device.
The first version of the purifier was developed in response to an existing and insufficient solution to the constant requirement for high purity water to service army aircraft and was this year deployed as the primary source of purified aircraft water to the Solomon Islands. Consistently converting 30-40 parts per million (PPM) total dissolved solids (TDS) water to 0 PPM TDS water at approximately 1000L/day. It received significant interest from the Royal New Zealand Air Force (RNZAF), Helicopter support and Solomon Airlines who all currently utilise the slow water distilling units which appear to be the standard industry solution. Lessons learnt from this deployment have been used to develop version 2 of the water purifier.
Version 2 is much smaller and features a higher quality suite of filters which are now capable of removing bacteria, parasites and viruses from the water source. The device can be powered by vehicle or mains power and with further development can be configured to utilise a solar and battery combination, becoming totally self-sustaining. Version 2 has been developed to use a combination of commercial-off-the-shelf (COTS) filters and a pump that can safely run dry without damage. The configuration of filters can be altered to achieve a wide range of forecasted purposes and favour high volume or high quality, depending on the requirements. Slight increase to size would also allow for a number of filters to be run in parallel, effectively doubling the output. This concept is easily scalable with capacity to produce several units using COTS materials. It weighs less than 10kg, requires very little operator training and has been designed to be robust. Filter replacement time frames can be established through further testing and a non-technical servicing stagger can be used to ensure that the purifier is always working at optimum capacity.
I propose further development and scaled production of my lightweight water purifiers such that they become an integral part of deploying vehicle complete equipment schedules (CES). The ability to produce 20L/hr of clean drinking water from any source will allow the decentralisation of water distribution and enable significant reduction to the logistics burden that is water transport and supply. The need for such a device has previously been identified by the US Army special operations; a requirements analysis was conducted and potential solutions assessed. The COTS options ranged from 35 – 55kg and could produce from 90 – 292L/day. The benefits of decentralised water production are real and the technology to do it at low cost exists.
Perhaps the next major HADR task will see MRH90 deploying suitcase water purifiers in place of bulk water, allowing communities to produce safe drinking water without a constant requirement for resupply.
by Captain Dael Liddicoat
The views expressed in this article and subsequent comments are those of the author(s) and do not necessarily reflect the official policy or position of the Australian Army, the Department of Defence or the Australian Government. Further information.