Because of increasing trade and the shallowness of the water the length was increased in 1859. The work was carried out by local builder, Mr Rowland Nutt. In 1869 it was again extended, making a total length of 711 feet (217 metres).
A hand crane was erected on the jetty in 1859 (or 1872) to assist in the loading and unloading of boats. This is the oldest such crane in South Australia. There was also a tram track from the jetty to Daranda Terrace to facilitate the transfer of cargo.
Between 1860 and 1880 Milang was one of South Australia’s busiest ports, connecting Adelaide, which was only 47 miles (87 km) away, with the thriving river trade which reached into the heart of the three Eastern colonies. Wool from the Darling and upper Murray stations was landed at Milang and then transported by horse and bullock teams to Port Adelaide. Wheat was transported to Milang and its flour mills and then shipped back as flour. Foreign goods shipped into Adelaide were then exported to Victoria and New South Wales through Milang, making over half of the Colony’s total exports in the years 1868 to 1872.
The Port of Milang declined in importance after the railway line to Morgan in 1878 took away the upper Murray trade and was further affected by the delay in obtaining a rail link of its own, which was not opened until 1884.