Captain Cook sailed into Cloudy Bay in February 1770 and noted that the landscape was covered with a forest of tall trees. Grovetown was initially known as Big Bush, a kahikatea forest of about 40 hectares, and was an island in the swampy area of the Wairau Plain. In 1858 Mrs Dick tells of her family arriving at Steam Wharf (Fell St, Grovetown) on the ‘Tasmanian Maid’. As the area was settled the bush was milled and timber was sent to other parts of the country using trading boats and the rivers before roads were accessible.
A cataclysmic flood of the Wairau River cut through land connecting the centre of the Grovetown Lagoon with the Wairau Bar to the east. Overnight the Maori community living at Wairau Pa was separated from its urupa (cemetery) and the Steam Wharf became inaccessible to coastal shipping. The urupa remains and is still used by Marlborough’s Maori community. The ships which sailed up the Wairau are long gone.
Boats travelled up the Opawa river when "Beavertown" (now Blenheim) was being established, and it became more favourable than the Wairau River.
Info from Grovetown.co.nz