Forestry Department amphibious dredge

This amphibious dredge was a one-off machine built around 1960 for a US Department of Forestry to clean salmon spawning beds. It was offered on eBay in 2002 from Grass Valley, California, described as able to travel on both land and water.

The dredge was built mostly of aluminium, including the hull. It carried two Buick V6 engines, two large pumps, four hydraulic winches and numerous water connections. It was completely rebuilt in 1983 at considerable cost and then used for a year on domestic holding ponds, after which it stood unused from 1984. At the time of sale it was described as rebuildable, complete except for its monitor (water cannon).

The same machine is shown in a French web history of Borg-Warner's Airoll tyre-chain track system, which says it used the Airoll mode of propulsion.