From Waiotahi Valley Road end follow the Waiotahi River which has numerous benched sections all the way up to a fork where the route leaves the river and heads up a spur. Follow the well marked spur up and over the saddle into the Kaharoa Stream. Follow the Kaharoa downstream to Te U Bivvy on the true left.
Note: At 2013, NZTopo50 BF40 Matahi map shows the ridge section incorrectly.