The Lower Moeraki River Walk is clearly marked on NZ Topo Map as a public loop accessed from the whitebaiters’ access road. In practice, the northern end is easy to follow but the southern end is somewhat obscure. It may even be hidden in places.
Having said that, it is worth the trouble with several points of interest. You will also notice a number of blue letter markers as you wander along the track. Wilderness Lodge Lake Moeraki maintains these to designate interesting flora. You need to be a guest there to get the matching guide notes.
Start on the Monro Beach Walk, but keep going on the access road to the parking area. There is access to a lagoon connected by a stream to the Moeraki River. The track is to the left and follows the stream before heading southwest to a private white bait facility. This is complete with a rather noisy power generator. Along this section, watch out for the letter “U”. The big tree in front of you when you see it is recorded as having over 100 kinds of other flora species growing on it, apparently a record.
Further along, the track runs close to the Moeraki River, which you can access in places. Then there are another couple of well-kept white baiters huts. After this, the track becomes less distinct, but continues on near the river to the signposted Rimu View Lookout. Right there are two ancient giants of the forest – a rimu tree and a kahikatea. It’s a few steps to a view down the river towards Wilderness Lodge Lake Moeraki.
Continue along the track for a few minutes to the exit to the Monro Stream. You should be able to see an unmarked turn-off. Follow this until you get back to the access road. Go left on the road and you will see the Monro Beach Walk return over the swingbridge. Worst case, walk onto the gravel above Monro Stream, turn left, and follow this back to where the road fords the stream. There may be some storm debris and you might get your feet wet with this option.