Wairau River and Diversion, Marlborough salmon and trout fishing
Sea-run trout, rainbow trout, salmon – plus whitebait, kahawai, red cod, and mullet in the lower rivers and river mouths
The Wairau River runs for 140km. The lower and middle reaches are braided over a wide shingle bed. For most of the year, only about 10 percent of the shingle bed carries water – often in a single channel. The upper reaches 100km inland from the sea are more confined over rocky ground. From the Sate Highway One Bridge at Taumarina downstream the river comes under tidal influence, is wide and slower moving. The river below Taumarina tends to be milky rather than being clear.
Self-contained camping is permitted at the Wairau River Diversion between the lower bridge on Neal Road and the mouth on the north side. This camping area is very popular with white-baiters during the season.
The reason the Wairau Diversion was constructed in the early 1960s was to prevent widespread flooding on the lower Wairau River plain. Heavy rain in the Richmond Ranges, which includes the main tributaries such as the Goulter, Northbank and Waihopai Rivers, would cause such massive flooding in Blenheim that the town was originally named the Beaver.
A major earthquake in 1848 caused a lowering of the Wairau Lagoons by 1.5 metres. This improved the flooding situation somewhat and allowed trading vessels access into the Wairau and Opawa Rivers. However, huge destructive floods still occurred in 1868, 1904, 1911, 1916 and 1923.
Through the work of various river boards, and eventually the Marlborough River Board between 1956 and 1989, stop banks and other works finally culminated in the opening of the Wairau diversion on 30 April 1963.The diversion created a new course for the Wairau River, which ran from State Highway 1 at Tuamarina, more directly to the sea at Cloudy Bay. The diversion straightened out the usual course of the river which meandered south-east before reaching the sea at the Wairau Bar.
The Wairau River mouth, and the mouth of the Wairau Diversion 8km to the north are good places to spin fish for kahawai from October onwards. The mouth of the Diversion tends to be swifter before Christmas. The river level can drop quite a bit during a dry summer. Then the mouth tends to follow the beach becoming less defined.
There can be excellent kahawai fishing at the mouth of the Wairau River, and at the mouth of the Wairau Diversion over summer and autumn. Following rain the Wairau Diversion, and the surf zone can become very dirty which is not good for kahawai fishing. Provided the river and surf are clear there will be a few kahawai present for certain. Often the kahawai are there so it is worth casting either into the lower river; or even straight out over the surf as far as you can cast.
Sea-run trout are caught early in the season while whitebaiters are still working the tidal zone of the Wairau River. Sea-run browns can be taken in the surf on spinning gear as well as further upstream.
Salmon in the Wairau River
A few salmon are caught each summer throughout the Wairau River. Occasionally salmon are taken at the mouth of the Diversion. These salmon tend to be taken on trout gear, including the fly-rod, rather than heavier zed spinners used to fish the bigger Canterbury rivers to the south. Fish & Game: Wairau River Salmon Running.
According to Nelson Marlborough Fish & Game field officer Vaughan Lynn there has always been a small salmon run in the Wairau River but it has remained relatively unknown. He believes the salmon run in the Wairau has increased over the last decade and more anglers have become aware of it and were now targeting the species. Data from spawning counts over the last seven years, together with catch reports, suggest the annual Wairau River salmon run be around 400-600 fish. There could be up to a 1000 fish in a good year – Nelson Marlborough Fish & Game.
Salmon fishing on the Wairau River is only allowed downstream of the State Highway 63 Wash Bridge. The river is closed to salmon fishing above Wash Bridge in order to protect spawning salmon.
See the nearby Opawa River.