Yahoo -it's been raining hard and has been for a few days. Organise a couple of strategic 'well' days at work and get to the Whakapapaiti.
From the SH47 bridge, there isn't a lot of time to think about much except how cold it is in the water, and how warm it was in the car. The water is continuous class IV, even-gradient rapids all the way to the confluence with the Whakapapanui. From here to the dam is much bigger, but less technical.
The Whakapapaiti is a faster, more technical run than its eastern cousing the Whakapapanui. Speed, and the river's continuous difficulties, combine to add an extra point to the classification, hence class IV. At some points channel decisions have to be made - and quickly. Once at the confluence with the Whakapapanui the speed eases but the volume increases, as does the size of the hydraulics. Have fun.
Whatever the flow at the Whakapapa Dam, the Whakapapaiti will have 40% of it - for example, if there are 50cu at the dam, the Whakakapapaiti will have roughly 20cu. So it needs slightly higher flows to make it worthwhile.
To get to the put in: find the Whakapapaiti bridge on SH47 just west of the SH48 turnoff to the Chateau. Scramble down the bank to the river. There is a parking area on the river left side of the bridge if you are leaving a vehicle.
To get to the take out: head east on SH47 for about 8km, look for a sign to Whakapapa Intake. Follow the road 8km to its end at the dam.
Egarr_Comments: numerous waterfalls