Ohau Valley

18 Ohau River

Access: Take SH57, the Shannon Road to Palmerston North, along McLeavey and Arapaepae Rds then swing R along Tararua Rd to Gladstone Rd. The Ohau Pipe Bridge is 5.9 kilometres from the Arapaepae – Tararua Rd intersection; it is the second bridge across the Ohau and carries prominent notices. The actual Pipe Bridge itself (unmarked on the 2002 map edition) is a few metres upstream of the vehicle bridge. A new Bailey bridge replaces the older suspension bridge, and light vehicles may be taken over this then past the water tanks to a small car-park at the end of Poads Road – 1.3 km beyond.

Overview: The Ohau Valley has one major sidestream, the Blackwater, and a couple of lesser headwaters. This terrace vicinity near the junction of Ohau and Blackwater is referred to here as żBlackwater Junction.

The Ohau is gorgy over much of its length, and most of the travel is in the streambed. This catchment was one of the most severely damaged in the 1936 storm, and off-track travel is still difficult. Trails from this road-end lead to the Makaretu, Ohau River, Waiopehu Hut, and the higher peaks of the Northern Tararuas. This entrance crosses private land but over which an access agreement has been negotiated. At the farm gate is an intentions book to be filled in. Dogs must be on a lead and firearms unloaded when on private property.

Inwards: The routes to the Ohau Valley and Waiopehu Hut start at the end of Poads Rd. A stock-proof gate on the L leads behind the barn and follows a pole-marked route down across the fields to steps alongside a gate. You may find the fragrant Pennyroyal, the small purple-flowered peppermint, across these paddocks. Through the gate, marker poles lead to a culverted stream. Keep to the high terrace here, and at the far end more steps cross the fenceline at the Park boundary.

These bush-edge steps mark the junction of three routes. Just inside bush-edge is the track to the Blackwater Junction and beyond; and 75 metres along this the track to Waiopehu Hut branches off uphill. Fifty metres before the steps, on the lower terrace, the track and concrete steps coming from the Levin Water supply intake will be found, with a vehicle track further to the L again. These both lead to the river and are used if one travels to or from Blackwater Junction by way of the river, rather than the track. This takes about the same time as the track, and as only a couple of the stream crossings (almost) require a swim, provides a pleasant alternative in summer's heat.

18.1 Ohau road-end to żBlackwater Junction QFG

Inwards: Inside the Park boundary, the track is level and well defined and crosses three minor streams before crossing Blackwater Stream on a suspension bridge. One minute past this lies the high terrace site of the old Ohau Shelter. Beyond the terrace you reach the Ohau River in a couple of minutes. From farmhouse to Blackwater Junction, a good hour. The rocky open section is about halfway along the track. Blackwater Stream itself may be reached from the TL of the Blackwater Bridge.

18.2  Waiopehu Hut and Waiopehu QFG

Seventy-five metres inside the bush from the Park boundary steps, the track to Waiopehu climbs steeply for a few minutes to gain the spur-crest, then somewhat more gently thereafter. The branch track coming directly from the Blackwater Junction is passed after 50 minutes, and 30 minutes further brings a stream crossing. This was the site of an old track-work camp – 75 m along the spurlet on the TR. A good hour from the track-work stream passes the site of Edwards Shelter. There is a water tank here but this welcome little shelter fails to meet modern standards, thus its future is in doubt. Beyond here the ridge undulates through the forest to reach an open spot on the spur; the site of two previous huts, in about 80 min. The earliest hut was blown off the ridge in the 1936 storm, and its replacement was snuggled in the ridge-side hollow. A fringe of bush gives way to healthy scrub, and a good 30 min brings the new Waiopehu Hut. This light and spacious new hut sleeps 20 comfortably, and is about (NZMS260 S25 091 507). Like other unheated huts above bushline, it may be cold in some seasons.

From Waiopehu Hut a fringe of bush gives way to scrubby tussock and the top of Waiopehu in 25 minutes. This fine viewpoint gives excellent views of the Northern Tararuas and the Horowhenua and is well worth the climb. The track sidles the actual summit of Waiopehu, somewhat softly, and just beyond the top a flat area on the right with a tarn marks the junction of the Oriwa Ridge. [An old Māori trail traversed Waiopehu and this tarn may well have been Pehu's water.] This trail may be re-routed over Waiopehu and away from the boggy sidle. From Waiopehu’s summit, choose your short-cut back to the sidle with care.

18.3 Waiopehu Hut to Te Matawai Hut QOT

From Waiopehu poles mark the route to Twin Peak, with its memorial trig, and a deepish saddle leads to Richards Knob, a good hour from Waiopehu Hut. (From here the Gable End Ridge leads to Blackwater Junction, an important escape route from Te Matawai if the rivers are too high.)

Beyond Richards Knob the track leads down through the bush of Butcher Saddle, 50 minutes distant; then a 25-minute climb to knoll 810 on the Ohau – Te Matawai Track. Forty minutes from this junction brings the huge helicopter clearing just before Te Matawai Hut. This hut sleeps about 60, has water tanks and a toilet.

Blackwater Junction vicinity

18.4 Blackwater Junction to South Ohau Hut QOT

Beyond Blackwater Junction the track continues over terraces for a few minutes to emerge on a bouldery beach. Note this entry point for the return journey. From here to the junction of the North Ohau, travel is up the stream-bed with several crossings, a few of which are swift even in moderate water. At night and by torchlight, it has been known for parties to travel up the North Ohau rather than the South.

From the Junction, a short gorge in the South Ohau is passed almost immediately, then 30 minutes of easy river travel gives way to 30 minutes of bouldery gorge travel. Once past a small stream from the TR the going becomes easier for the final 20 minutes to South Ohau Hut site: 2 hours from Blackwater Junction. Sleeps 12, water from the stream, has a toilet.

18.5 North Branch, Ohau River QOT

From the junction of North and South Ohau, a short gorge section leads to easier going in the North Ohau and to the old biv site (NZMS260 S25 133 547) in a good hour. The upper reaches and eastern faces of this stream were seriously damaged by the 1936 storm, and much of the spur travel remains rough.

18.6 Deception Spur to Avalanche Flats QBN

Inwards: Deception Spur lies between the North and South branches of the Ohau, 40 minutes above Blackwater Junction. This spur is nowadays a route only, though it was a common track before the 1936 storm. This route to the Mangahao may be re-opened some day. Quite rough low down, the spur soon becomes a steep climb through windthrow and lawyer, and passes a couple of minor saddles before emerging on the main ridge near 865, just past an open stretch. About 2˝ hours.

From here to Avalanche Flats it is perhaps best to travel SE along the ridge until 200 metres past a small open slip on the R, from where a NE spur provides good going right to the Mangahao Valley, just above the old Avalanche Flats Hut site. About 4 hours from the Ohau junction. The new Mangahao Flats Hut is downstream a good 50 minutes on the TR at (NZMS260 S25 159 543). But Avalanche Flats is always a nice camping spot.

Outwards: On the outward journey, this spur is picked up on the TL of the Mangahao, upstream of a tiny creek, just up from the old Avalanche Flats hut site. Deception Spur will provide no problem to those adequately versed in bushcraft.

18.7 Gable End Ridge QOT

Up: Just beyond the high terrace at Blackwater Junction this track heads steeply up a small rocky step to the bushed spur, which moderates after 20 minutes or so. Beyond this it rises steadily over Mayo Knob to exit the bush-edge just before Gable End, about 2˝ hours from the Blackwater Junction. Beyond Gable End the track is essentially in the open tussock and scrub, and reaches Richards Knob in another hour. There are fine views en route of North Ohau River and of the tops of the Northern Tararuas.

Down: Richards Knob, about 50 minutes from Butcher Saddle, is not far above bush-edge, and the track junction is obvious. The track is well padded though a little obscured by long grass at times, and travels over a couple of knobs to reach Gable End and the bush beyond: about an hour from Richards Knob. The track then drops through the bush, past a longish flat section and over bushed Mayo Knob, followed by a steeper drop down to the Blackwater Junction. Like many tracks in this area, it may have some soft going.

18.8 Blackwater Junction – Waiopehu Hut QOT

From the TL of the Blackwater bridge a trail will be found leading upstream for 100 metres to the Blackwater itself. About 2 hours will find you in the small stream just E of Bush Corner on the Waiopehu Track. Near (NZMS260 S25 090 520) is a small waterfall, easily scrambled up, and a few minutes upstream of this is a steep re-vegetating slip on the TL. Climb this and the bush spur beyond to gain the Waiopehu Track about 15 minutes below the old hut site.

18.9 Blackwater Junction to Poads Road-end QFG

Outwards: Travelling from Blackwater Junction to the road-end, the track first leads up the Blackwater to cross the suspension bridge. Between here and the farmland it passes three small streams and is well padded. At the bush-edge steps, follow the marked route across the paddocks and behind the barn to the gate at the road-end. Fill in the intentions book at the farm gate as good practice. One hour from Blackwater Junction to the farmhouse is a good time.

A most pleasant alternative to the track on a fine day is to travel down the river to the farmland. This route takes about the same time as the track, and there are only a couple of minor swims en route. Gain the river, either from the track 4 minutes beyond the high terrace or via the track upstream of the TL of the Blackwater bridge. The exit at the Ohau (Levin) water intake is obvious and leads up the concrete steps to the grass flats just by the bush-edge stile. Take care to not pollute the water supply and keep clear of the intake structure.

18.10 Blackwater Junction to Waiopehu Ridge QOT

From the TL of the Blackwater bridge, this trail climbs almost immediately to reach the Waiopehu Ridge in an hour, about 15 minutes short of the camp stream. This is labelled as "6-disc track" at the top.

South Ohau Hut vicinity

18.11 South Ohau Hut to Te Matawai Hut via Girdlestone Saddle QOT

Up: From South Ohau Hut, proceed up the western headwater. Keep R at the first significant fork and L at the next one, some 30 minutes from the hut. Both forks are cairned. Twenty-five metres beyond this second fork, the Dowling Falls by-pass track climbs 40 metres on the TL to a spur, which it follows for a few minutes before dropping steeply to the stream again. At the next fork turn L and, 15 minutes upstream, a small and almost dry gut joins from the TL. A cairn here marks the start of the steeply climbing route, poorly marked, that reaches Girdlestone Saddle in 15 minutes, some 90 minutes or so from the South Ohau Hut.

To Te Matawai Hut, the good uphill track heads SSW from Girdlestone Saddle, and in less than 1 hour the small knob will be reached where it joins the track running from Te Matawai to Pukematawai. Turn R down into the scrub, and Te Matawai Hut should be reached 75 minutes from Girdlestone Saddle.

Down: Twenty minutes towards Pukematawai from the hut is the Girdlestone Saddle turn-off, and the well-marked and gently padded track drops to Girdlestone Saddle 50 minutes from the hut. There is a blank metal fingerpointer at the saddle, but the junction is not otherwise well marked. The track branching SE to the Mangahao is well cut, but that heading NW to the South Ohau is only lightly defined.

The South Ohau headwater stream is reached 10 minutes from the saddle and opens out somewhat in another 10 minutes. A tiny stream joins from the TL and, almost immediately, cairns on the TL mark the start of the sidle that thoroughly by-passes Dowling Falls. A spur is gained some 20 metres up, and this is followed to eventually regain stream level in 20 minutes, about 25 metres upstream of a major fork. The two notches on the bypass spur mark the crossing of recent Otaki – Mangahao Fault traces. These faults are possibly connected to the origins of Dowling Falls lying to your R and more falls up the stream branch to your L.

Twenty-five minutes below these forks and down a short gorge, South Ohau Hut is reached, perched on its high terrace, some 75 minutes from Girdlestone Saddle.

18.12 South Ohau Hut to Te Matawai Hut via Yeates Track QOT

The 'Yeates 600' (feet) is the abrupt climb behind South Ohau Hut where the trail climbs steeply for 35 minutes before suddenly easing off. The spur turns R and rises more gently for the remainder of the Yeates Track to meet the track from Butcher Saddle at point 810, about 75 minutes from South Ohau Hut. Te Matawai Hut is about 35 minutes from this junction, just beyond the huge helicopter clearing. This hut sleeps 60 or so. About 2 hours in total.

Emergency exit. Gable End Ridge or Waiopehu Ridge are both good alternatives to a flooded Ohau River. At present Aussies Track, from Ohau Forks to Blackwater Junction, offers a route on the TL but this may be subject to rockfall. See 18.4.

18.13 South Ohau Hut to Butcher Saddle QOT

This route to Butcher Saddle offers practice in sidling waterfalls. Fifteen minutes from South Ohau Hut up the easy terraces of Butcher Creek brings an obvious fork. Take the L stream and after 25 minutes of quick easy height, the first waterfall comes into view. The first two or three falls are simply passed, but their successors become more troublesome and continuous. Intermittent deer trails offer a sidle about 50 metres above the stream on the TL and, once beyond the second small streamlet, the upper basin is regained just before the final pull to the saddle.

From here one may drop into the upper Otaki in 30 minutes; and the best sidling of these falls is on the TR.