With the settlement of the Wairau Plain there became a requirement for supplies and a method of dispatch for produce. Since any route from Port Underwood was impractical, the only other option was the use of the Wairau mouth. Soon small ships began off loading their cargoes just inside the Wairau Bar to a series of stores on the Boulder Bank. As the centre of colonisation shifted to Beavertown (Blenheim), some kilometres inland, horse drawn whale boats were used to carry goods up the Opawa River to a wharf on the Taylor River.
In 1855 a major earthquake struck which lowered the level of the land about a metre to make the entire Opawa river navigable to Blenheim. Within a short time fleets of small ships plied the Opawa trying to gain a share of the colonial trade between Blenheim and Wellington. In 1879 the port was shifted to deeper water several hundred metres downstream making it possible for several steamer companies to begin operating. The port itself was a collection of warehouses with wharf frontages. To avoid flooding these were set on tall piles and except in high water, all goods had to be winched up. The greatest dilemma of the shipping companies was not flooding, but rather shoaling at the Wairau Bar. Numerous ships were stranded there on sand bars and several were wrecked completely. Eventually a pilot was employed full time at the bar to take soundings of the channels, guide ships across and in the case of a stranding, winch them off.
By 1900 activity at Port Blenheim were dominated by T. Eckford & Co. Ltd who operated a small fleet of ships. The crossing originally took 10 hours but with new diesel engines the time was cut to 8 hours except in bad weather when ships were redirected to Picton. In 1954 with the laying up of the S.S.Wairau owing to lack of trade, The A.S.Echo became the only ship making the Wellington -Blenheim run. The final blow to Port Blenheim came in 1965 with beginning of the Picton rail ferry service by the Aramoana. T. Eckford Ltd. & Co. closed its doors and laid up the Echo and in 1968 after 89 years of operation, the port closed officially.