The lower Whakapapa is an underarted gem. Overshadowed by the awesomeness of the upstream reach. It is well worth a look. Below Owhango 42 Traverse Bridge there are a few hours of II+ to Kakahi and then a few more hours Class II on the Whanganui down to Pariaka.

Shuttle
Put-in
The Put-in is at Ohinetonga Road on the 42 Traverse near Owhango. Downstream of this there is a take-out at the end of Te Rena Road Kakahi (7.5km down river from Owhango).
Take-out
The usual take-out is at Pariaka Power Station on the Whanganui downstream of the outflow.
On the River
It is fun to lower boats from the bridge on true right and then scramble down the narrow track to put-in below the Class III+ / IV rapid upstream of the bridge.
The river starts with fun Class II boulder gardens for a kilometre or so. This is followed by three meatier rapids of Class II+ / III.
It can take a few hours to cover the short distance to Kakahi and also faffing at the put-in so allow plenty of time.

Boat scout diligently and, where you can’t see clearly, shore scout as required. Always think about portage if the flow is low enough to expose a lot of bone breaking boulders.

There are some fun ledges on the Whanganui in the last 2km before the intake.
About a kilometre from the take-out there is a weir for the power station – climb carefully down the channel that looks like it has the most water. Please don’t cross the private land to short cut this last hurdle.
Allow 5 hours in total down to Pariaka.
There is a camping area that can be rented out on the true right just before the river is ponded behind the intake (Pukeko Nest – Suzanne Mickleson). Associated with the same property is a cottage for rent.
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Gauge
The gauge is the Whakapapa below intake
It has been scratched down at 3 cumec by keen packrafting trout anglers. A better minimum flow would be 7 cumec. Release flows require a natural flow of 16 cumec and are often called off.
Flash floods down this catchment are not unlikely so go after rain not during and be very mindful of the forecast.