The volume of freight and grain moving through the Snake River dams increases every year, and rumors to the contrary are wrong, members of a federal advisory committee say. "I think that is a misconception that is out there that should be debunked," the chairman of the committee, Spencer Murphy, said. "To replace that amount of tonnage would require over 162,000 trucks or 42,000 rail cars." Moving goods off the water onto truck or rail would lead to more air pollution, carbon dioxide emissions, diesel fuel consumption and more traffic fatalities and personal injuries. Moving goods by water is the safest and most efficient means available. "If you are trying to make an environmentally conscious decision of how best to move freight ... you should be putting as many goods on the water as possible and removing them from truck and rail, and not the reverse," he said.