Slide 6.   Gravity feed of water from an on-farm water impoundment ("ring tank") into the on-farm water distribution canal.  The rink tank in this photo from Colly Farms, near Moree in Northwest New South Wales, has a capacity of approximately 1500 megaliters.  The volumes of water involved in filling distribution canals and ditches, before ever delivering a drop of water or gram of dissolved chemicals to the cropped fields, provides a significant barrier to use of canal dissolution of chemicals, like PAM, for application to the fields, particularly given the high rate of PAM adsorption to surfaces and solids.  When applying PAM to this water distribution system in the ditch the efficiencies of PAM delivery to the target fields has been low, significantly raising the PAM application cost.  New efforts are underway to adapt American direct field application strategies, to the larger, and more automated field management schemes on farms such as these in Australia.