Every time some short-thinking state decides it would be a great idea to dam up a river and swamp dozens (or hundreds) of square miles of forest land, a kazillion trees are drowned in the backwater. Drowned, but not necessarily wasted. Forests die beneath the chilly water, but remain perfectly preserved for many years, and their lumber is still usable. Until recently, it was not possible to harvest drowned forests.
Triton Logging has created a remote-control submersible called Sawfish. Wielding a pair of giant pincers and a 54-inch chainsaw, the craft grabs hold of a tree at the base, jams a balloon into its trunk and inflates it, and cuts through its trunk in a few seconds flat. The tree floats to the surface, where it’s dropped into a “bunk.” Waterlogged trees are hauled off by barge, hundreds at a time. Wired, in Reservoir Logs:
There are environmental advantages to the Sawfish method as well. Conventional aboveground harvesting contributes to deforestation, a cause of global warming thatâ€™s responsible for the release of 25 percent of the worldâ€™s CO2 emissions. But because underwater trees are already dead, cutting them down doesnâ€™t worsen the situation. And with underwater logging, there are no unsightly clear-cuts and no spotted owls to worry about.
The supply of submerged trees is immense:
Most salvage loggers believe that reservoirs conceal 200 million to 300 million trees worldwide. â€œThatâ€™s a low estimate,â€ Godsall says. â€œWeâ€™re continually discovering reservoirs with trees in them. Thereâ€™s one in Brazil called Tucurui with $1 billion worth of timber.â€