Park at 21 18.640 157 46.918. You must take a short walk through a
residential area to get to the trailhead, which starts just after
the pumping station. The road will narrow quickly to a trail (keep
to the left to ensure you do not go on private property), and you
must now follow the Bonzai Pipeline. You will cross the stream
several times, be careful on the rocks, they are slippery, and your
socks could get wet!
When you get to 21 18.932 157 46.694 you will have a decision to
make. You can either take a switchback trail up the ridge or climb
up the waterfalls with the assistance of ropes. To take the
switchbacks, cross over the pipeline and head to the left. Follow
up this trail, and it will eventually lead you to the Ka’au
Crater rim. You will need to take a right when you get to the rim,
and follow the trail down until you reach the point where the water
exits Ka’au Crater. This route would probably rate a terrain
difficulty of 3. To climb the waterfalls, continue straight at the
waypoint and follow the likely trail. At the base of the 2nd
waterfall, you will see the start of the ropes to help you. As
always, test ALL ropes with your full weight before using. And if
you are unsure, you can always turnaround -- no cache is worth
major injury. This route is better attempted on a relatively dry
day.
Stand where the water exits the crater, and face into the
crater. You will need to climb a steep bank to the right of this
spot. You are almost there!