Also known as: Wang Chu, Thimphu Chhu, Raidak
Beautiful canyon just downstream of Thimphu; Chuzom confluence marked by three chortens; Tashichho Dzong is in Thimphu upstream

Whether there is a river here on your dates, and what kind of water it is.
Himalayan snow/glacier and rain fed; recommended low to medium flow; no gauge. Confirm.
Spring and Fall at low-to-medium flow; monsoon ~Jun-Sep high and dangerous; no gauge, judge visually. Confirm.
Spring and Fall; operators cite Mar-Apr and Nov-Dec. Confirm.
Snow/glacier-fed cold water, drysuit/wetsuit advisable in spring/fall (est)
Monsoon high flows and flood risk; no gauge means visual judgment required
A river changes grade with its level. These grades describe a normal flow - in flood the same run is harder, and often a different run entirely. Check the gauge before you commit.
Class V (Wang Chhu, Class V skills required); Class III+ (Thimphu Chhu reach)
Kayaking (expedition); Rafting (Thimphu Chhu reach)
Less-experienced group runs only the Class III+ Thimphu Chhu (Road Bridge to Chuzom); strong Class V paddlers continue Chuzom to Damchu
Thimphu Chhu III+ suits intermediates and guided rafts; Wang Chhu experts only, must commit to whole run with little road access
Big ugly Stupa Drop V+ immediately below Chuzom bridge (commonly portaged right); huge midstream boulder just below; Alu Dorji's Drop V; non-stop boily water
Stupa Drop V+ commonly scouted/portaged right; blind boulder immediately below; boily aerated continuous water; limited scouting
Wang Chhu - Chuzom to Damchu (Class V); easier Thimphu Chhu - Road Bridge to Chuzom (Class III+)
Solitude/remote; far less commercially run than Punakha rivers; little road access on lower reaches
Sustainable Development Fee USD 100 pp per night (Sep 2023-Aug 2027); visa via licensed operator; lower gorge below Chuzom access restricted by dam construction. Confirm.
Permits and operators change - confirm before booking.
Thimphu Chhu put-in via dirt road to an unnamed bridge (rapids scoutable from road); Wang Chhu put-in at Chuzom road bridge junction; Damchu take-out needs hiking the boat up river-left
Road shuttle along Thimphu-Paro and Thimphu-Phuntsholing highways; Chuzom is a major junction
None documented on-river; short day runs; hotel lodging in Thimphu/Paro
Self-support Class V kayaking gear, throw ropes, scout/portage readiness; Thimphu valley has coverage, lower gorge patchy (est)
Thimphu and Paro; operators (Truly Bhutan, Druk Asia) mostly run Punakha rafting
Continuous boily Class V, blind boulder below Stupa Drop, hard scouting; downstream dam construction (Chukha, Tala) restricts lower gorge; river becomes the Raidak in India
Thimphu Chhu road parallels/crosses run for feasible egress; Wang Chhu limited - commit to whole run; no organized river-rescue noted
Independent travel not permitted for most foreigners - licensed Bhutanese operator/guide effectively mandatory; Class V run needs expert self-supported kayak crew
This profile is desk research, compiled from public sources - not a first-hand river run report. Coordinates are approximate.