Wairau (II / III) (- IV in high flow)

A real gem of a river that only Blenheim paddlers seem to know about.  The Wairau River is the largest river in Marlborough. It drains an area that is in a rain shadow, so it’s best in spring with snow melt.

In higher flows the Wairau could be run as one continuous paddle from Hell’s Gate above the Rainbow confluence to Blenheim. But below SH63 the river is low key and the domain of multi-sport training.

The entire run from Coldwater Creek to SH63 is possible as a day trip. Most will opt to miss out the slower sections by multiple car shuttles and repeat the best bits in preference.

It’s a dry part of New Zealand so kayakers find it hard to catch it at a decent flow, but the flows Packrafters can cheerfully navigate lie within the normal summer flow range. The Rainbow tributary has also been Packrafted but is usually too low to paddle.

It has some tributaries that haven’t been run, and one that has only been packrafted.  This river has multiple day runs, some potential for longer trips, and tributaries that are accessible from the Travers and from the Waihopai and Leatham headwaters. 

Hugh Canard’s river notes and advice and Eggar’s South Island River guide supplemented our scout of this river.

To Get to the Put in

To get to the take out turn off SH63 between Blenheim and St Arnaud at the signs to Rainbow Valley Ski Area (this turn off is about 10 km east of St Arnaud). Drive approximately 12 km on the gravel road to Woolshed Flat /Dip Flat turn off. Park here or head up to park at next stream after the entrance to Rainbow Ski Area (a further 5 km). To get to the Hamilton Reach put-in, continue up the valley for a further 10 km past the toll gate (locked in off-season) to the old Rainbow Homestead where there is a toll booth. There is a road maintenance toll to proceed beyond this point. The toll road beyond this point is usually open between Xmas and Easter.

The take-out for the Hell’s Gate reach, where the valley markedly narrows, is 7 km past the Toll Gate. A further 3 km through the gorge is the Coldwater Creek campsite and put-in for the Hell’s Gate reach.

Access can be arranged outside of this period.

View Larger Topographic Map

On the Water

The best rapids exist in the Hells Gate and Hamilton beats. These reaches are separated by some Class I and II water, that most will avoid with a car shuttle. Below Hamilton’s there is some Class II and then Class I and II braided river (of limited interest to packrafters) all the way to the coast.

Hells Gate (III) Reach

The upper Wairau above Coldwater Creek has a different character and would require quite a bit of water to be viable. The Hell’s Gate section is the highest that kayakers venture. It runs between Coldwater Creek and where the valley opens out a few km above the Rainbow River confluence.

Quite a bit of this section can be scouted from the Rainbow Road which travels beside the river. You can start at either Coldwater or Jacobs Creek confluences. It starts nice and easy and slowly ramps up. At Hell’s Gate, where the valley is most constricted there is a nasty undercut on river left that may not be obvious at higher flows.

Most of the river is boat scoutable (you’ve also had a chance to look at it from the road). When a large boulder appears river left get out and scout the crux rapid.

The rapids are fast, exciting and very technical Class III. With a flow of 10-20 cumec (Dip Flat gauge) they will be bony technical Class III. They will go to Class IV with very high flows (above 50 cumec). The rapids extend for over 3 km and then ease towards the bridge.

Bridge Beat (II) & Connor’s Creek Beat (I)

Rapids ease from the bridge through to the Rainbow river confluence. From there, the river is Class I down to the confluence of Shroder’s Creek. At higher flows it will be possible to scratch through this reach.

Rainbow Homestead to Six Mile Creek [Irishmans & Hamilton Beats] (III/IV)

This section starts at the old Homestead near the toll booth. The rapids from Shroder’s Creek increase to Class II and will reach Class III in high flows. They are continuous right down to, and beyond, the crux Hamilton’s rapids. This section just gets harder as you progress. It starts easy, starts closing up and the rapids demand more care.

The Hamilton rapids begin a little above where the Hamilton River and Lee’s Creek flow in from opposite banks. As the forest closes in the gradient suddenly increases and the river swings to the right and a swingbridge comes into view.

Eddie out and inspect the rapid before proceeding. The swing bridge gives the best view of a Class III/IV rapid you will ever enjoy. The footbridge is a great location to scout, shoot photos or observe paddlers. The crux of the rapid is immediately under the bridge. Plot a course through the tight gaps below the first two drops and look at where you can best eddy out, to boat scout and set rolling safety as you progress.

The main rapid is over 100 m long. The current line (June 2020) is river right over the first drop and then down the center channel through the main drop which is under the footbridge. Several more steep tight boulder drops require precise maneuvering, so eddy out regularly to determine the best path.

Set safety from the shore for each drop and think carefully before running it at higher flows. The rapid reaches Class IV at high flows with holes developing behind boulders.

Six Mile Creek to Dip Flat Beat (II/III)

From the Hamilton rapids the river eases off with occasional rapids which are up to Class II+ or III at first but soon drop to Class II by Dip Flat.

Woolshed Flat to SH63 Reach (II)

After Dip Flat the river eases to Class II. The river becomes increasingly braided over shingle down to SH63. There are multiple take-out points depending on the river flow. Merry Creek is a good take-out in summer flows. You will be able to go lower in spring flows.


The gauge is Wairau at Dip Flat. The flow at Coldwater Creek is about a third of the Dip Flat flow. A minimum flow of 15m3 at Dip Flat is recommended for Hell’s Gate.



There is a small DOC campsite near Coldwater Creek. It’s cold in winter!

Below Hamiltons there are nice flats on Rainbow Station amongst the forest and manuka but these areas require permission to camp.

A Multi-day Trip by Motueka Highschool at Low Flow

The Road is Rough with Fords

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