The Lend-Lease Act of February 1941 was enacted by Roosevelt to supply war materiel to the Allies at little cost, or with some reciprocal payment or services, to aid the Americans. Once America entered WW2, the reciprocal services to the Americans took on a more important tone. For example, Australia made 3 new civilian hospitals available to the U.S. forces, to the exclusion of Australian civilians. Much free housing, free food, and sizeable buildings were given to U.S. forces for their use whilst based in Australia. This was regarded as a sizeable level of reciprocal payment by the U.S. for Australian L-L equipment.
When Roosevelt proposed Lend-Lease, he explained to the public and the press that his plan was comparable to one neighbor lending another, a garden hose to put out a fire in his home.
Roosevelt said, "What do I do in such a crisis? I don't say - 'Neighbor, my garden hose cost me $15; you have to pay me $15 for it' - I don't want $15 - I want my garden hose back after the fire is over."
This indicates that Roosevelt fully intended serviceable items to be returned to the U.S after the War.
However, a substantial number of heads of American industry, pressured both senior politicians and important senior military leaders, to ensure that no Lend-Lease equipment was ever returned to the U.S - as they feared the massive supply of war equipment being returned to America would depress new equipment demand, and prices - for perhaps 10 years of more.
There was one final important factor that few foresaw - a desperate shortage of shipping at wars end. Practically every ship that could carry personnel and cargo, was pressed into service to carry nothing but military personnel, who were desperate to return home, seeing as the War was over - and many had been away from family and friends for 3 to 4 years or more. As a result, a lot of L-L equipment was often abandoned where it lay, as troops had only one desire - to go home and enjoy their well-earned peacetime.
As a result, the combination of pressure from industry heads and the shortage of shipping, saw vast amounts of U.S equipment dumped.
Having spoken personally to many WW2 veterans when they still had fresh memories, many spoke of the large amount of L-L equipment dumped.
The dumping, however, was often frantic, dependent on the attitude of the local CO, and ill-thought-out. Much L-L equipment was poorly stored and deteriorated rapidly after Wars end. A lot was simply stolen as soldiers abandoned areas they had occupied, and there were few people left to guard it.
In the Northern Territory of Australia, Willys Jeeps were driven into deserted semi-jungle areas, the engine oil drained and they were left running with a brick on the accelerator.
Trucks, items of plant, and other types of machines met a similar fate. Some were simply burnt where they stood. However, after all the Americans left, locals merely retrieved salvageable equipment and repaired it to working condition.
Many of these items of equipment were well-worn, having endured at least 2 and sometimes, 4 years of war use. However, there was a lot of new L-L equipment, that was in storage in warehouses.
Some of this was destroyed by dumping, a lot was just abandoned to the care of the Australian Govt. Where ships and crew were available, L-L items were taken from stores and warehouses, and dumped overboard in deep water.
The Perth Canyon, West of Fremantle, Western Australia, is one resting place for quite an amount of new L-L equipment. My father spoke of witnessing the loading of substantial amounts of L-L equipment in Fremantle Port during late 1945 and early 1946. There were a lot new Jeeps and trucks dumped, many still in corrosion-resistant coverings and coatings. The water depth in the Perth canyon varies between 700 metres and 4000 metres, and much of the underwater landform is very steeply-sloped.
However, the Australian Govt decided (possibly before the Wars end) to acquire as much of the useable L-L equipment that had survived the War, to assist in the post-War recovery and development of Australia.
There was also the issue of U.S military-owned equipment that had been abandoned in Australia at the end of the War - and the Australian Govt set out to purchase this as well.
Australian Govt representatives spent a great deal of time in the U.S in late 1945 and early 1946, endeavouring to come to an agreement for the purchase by the Australian Govt, of all the residual and salvageable L-L equipment and stores, as well as the U.S military-owned equipment and stores left on Australian territory.
The Americans demanded a huge sum initially for all this equipment and stores - much to the despair of the Australian Govt representatives. However, after an extended period of bargaining, the Americans dropped their asking price for the equipment and stores to a figure that was around 5-10% of the initial asking price.
The Australians then agreed to pay this purchase price, and once this agreement was in place, the Australian Govt then arranged to sell the equipment through the Commonwealth Disposals Commission, which had been instigated in 1944 to oversee an orderly disposal of War equipment.
This Govt agency oversaw the auctioning and placing out to tender, of every item of War Surplus, as well as Australian Govt items deemed as no longer needed in peacetime.
The CDC sales operated on a regular basis from 1945 to 1949.
Military aircraft and items such as weapons were deemed to be a major problem as regards disposal to an Australian civilian population, and thus, nearly all were either destroyed and sent to scrap dealers to be melted down - dumped at sea - stripped for valuable scrap metals and components - or just plain burnt.
As far as items on the seabed being in "good condition" after 70 years in that location - then ones definition of "good condition" must be stretched quite substantially to believe that.
Sea water is exceptionally corrosive and little remains but the outline of frames after 70 years on the seabed, even in "favourable" underwater conditions.
Demobilisation of the Australian military after World War II - Wikipedia, the free encyclopedia