When tourists come here, they should follow the guidelines about what to do with their rubbish. They shouldn't ask for hot showers they don't need — those cost a lot of precious firewood. Foreign trekkers put a heavy demand on the wood supply; in places along the trekking routes, household fuel consumption more than doubles during the season.
Every campsite we've inspected in recent years shows some degree of pollution and damage — rubbish left by trekking groups or their support staff, uncovered toilet pits, drainage channels dug wherever it was convenient.
The hot spots of environmental degradation are the camp areas in the sub-alpine and alpine zone — fragile, easily trampled, and often right next to water that can't handle soap, shampoo, or human waste.
There's rubbish everywhere; people just throw things wherever they stand. But it's not always the tourists who leave it behind — more often it's their support staff. What tourists can do is set an example. They should explain to local people why keeping the environment clean matters, not just leave it to us to say.
The damage isn't caused by trekkers alone — but it still falls on the mountains to carry it.