The confluence of the Po (flowing south in upper left) with the Yarlung Tsangpo in the Great Bend of the Yarlung Tsangpo. Space Imaging Archives archives (http://www.spaceimaging.com/gallery/ioweek/archive/02-05-19/index.htm)
2002, Yarlung and Po Tsangpo in Tibet
In November, 1998, Wick Walker arrived at Pei, the entrance to the gorge, with a team of four American kayakers who attempted to boat it at a flow around 40,000 cfs, but one of them, Doug Gordon, drowned about 27 miles below Pei, ending their expedition (see link to 1998c).
On another 1998 kayak expedition, this one organized by Steve Currey, Scott Lindgren planned to run the Great Bend, referred to as the Everest of rivers, but cancelled due to high water a week before the Walker team arrived in Pei. Instead, he ran about 10 miles of the Po, a large tributary that enters near the crest of the Great Bend (see link to 1998b, upper Po).
The 2002 expedition, which also began at Pei (29.521640°, 94.881911°) was sponsored by Outside Magazine and Chevy Avalanche. Lindgren planned this trip for February, when flows are lowest, to maximize the possibility of completing the 100 miles or so that Walker's 1998 team had been unable to run at flood levels. The team of seven of the worlds most experienced kayakers was able to boat 44 miles from the put-in at Pei (29.521640°, 94.881911°). This was 17 miles further than Walker's team had boated in 1998 - from the rapid where Doug Gordon drowned, near 29.758318°, 94.970550°, to a half mile above Hidden Falls (29.775063°, 95.186820°). The expedition is better described as kayak packing - they carried their boats a much greater distance than they paddled them. Both the river and the trail were Class 6+.
Flow was estimated to be about 15,000 cfs. The average gradient was about 85' per mile, very high for these flows. The video produced by Outside (Into the Tsangpo Gorge) shows very dramatic footage of some of the rapids.
Knowing they would need to portage Rainbow and Hidden falls via an 11,000 ft pass, the team hired a several Nepali and about 70 Tibetan porters. Unfortunately, the team had problems with the Tibetans, who, according to author Peter Heller (Hell or High Water), felt they were seriously underpaid for the difficulty and hazard of the portage and nearly rioted to get the team to pay them what they considered a fair wage. Even more unfortunately, both the Outside Magazine web site, their print article describing this expedition (July 2002, page 82) and the video leave the reader with a negative impression of the Tibetans porters. If you lived in a culture that had been abused by foreigners for centuries, you'd understand why they felt abused. Even the British invaded and captured Lhasa for a few years (1904-07), killing stone throwing Tibetans with rifle bullets. It takes a lot of effort and patience to overcome this aspect of working with Tibetans, but the result is well worth it. Hopefully future expeditions will learn that even though Tibetans are not accustomed to the income that foreigners enjoy, Tibetans should not be treated as poor people who don't know their worth. They have adapted to living in an environment where most other people would never survive.
After exiting the Great Bend, the team ran the Po Tsangpo to its confluence with the Yarlung Tsangpo (29.875629°, 95.122369°), completing the section Lindgren and Munsey had attempted to run at flood levels in 1998 (see 1998b). However, the flood resulting from the failure of a natural dam on the Yigong (a large tributary to the Po, see Parlung, 1999) had scoured the river banks below the confluence in 2000, making it impossible to scout or portage the Yarlung below the confluence, so this section has not been explored as of 2008.
References: July, 2002 Outside Magazine article, also online at Liquid Thunder. The video "Into the Tsangpo Gorge"may still be available from OM. Michael McRae in his 2002 book, "The Seige of Shangri La," does an excellent job of summarizing the history of exploration of this area. Peter Heller's "Hell or High Water" (2004) describes this trip in detail.