Since I knew nothing of these units I snipped something here for those in the same boat,
...taken from......http://www.sfu.ca/casr/ft-column1.htm
The security component of DART will be needed to protect the large ROWPUs. Such an advanced water purification unit would be a valuable prize for any leader of a militant group trying to win the hearts and minds of local Sri Lankans.
There is a theoretical efficiency to having a large, centralized source of water with an output that is absolutely pure, and a flow-rate of tens of thousands of litres per day. Such a unit would make most sense if it were to be set up in downtown London, Ont.
For the current purposes, however, we must take other factors into consideration. DART's initial deployment required two of the largest cargo planes on the planet. The ROWPU components must be housed in ISO containers â “ the 20-foot long steel shipping boxes more commonly seen being hauled by a train, rather than by a truck.
Trucks must haul their technologically vulnerable cargo over inadequate roads. Then, after each large ROWPU
is set up, it requires three technicians to keep it running. The CF also uses the so-called Mini-ROWPU which can be broken down into three separate loads for shipping. The volume of water processed by Mini-ROWPU is less than a large ROWPU but, once set up, the Mini-ROWPU require only a single water technician to keep it working.
In view of the difficulties of deploying 'full sized' ROWPU, the trade-off of a reduced output from Mini-ROWPU seems acceptable. If larger numbers of the Mini-ROWPU made up the DART water purification component, greater flexibility in both shipping and 'in-country' location could be realized. Each smaller unit could be set up and left with one qualified technician and a CF security team to protect the installation. Then the rest of the convoy could move on to the next logical location, set up another Mini-ROWPU, and so on. Transport problems (and scale) could be reduced while the requirements for qualified water treatment technicians would remain the same.
In the long run, Canadian personnel (either CF or CIDA) could train local technicians to maintain the Mini-ROWPU which could be left in place. Who knows? It could act as an incentive to order more Mini-ROWPUs from Canadian industry for the future. The whole world needs water. There is a long-term market for ROWPU technologies.
...EDIT..and here is the company alledgedly suing the Govt.
http://www.zenon.com/markets/military_minirowpu.shtml