With the onset of the Long Depression looming, the construction work on the line provided valuable employment, and as it was built, it was progressively opened.

[1] In 1886, a privately owned narrow-gauge bush tramway was built into the hills behind Mount Somers to serve coal mines and a limeworks.

[2] The following stations were on the Mount Somers Branch (in brackets is the distance from the junction at Tinwald):[2] For roughly half a century a daily mixed train operated on the line.

Besides coal and limestone, important commodities on the line were grain, livestock, and silica sand that was railed to a glassworks in the Christchurch suburb of Hornby, served by the Southbridge Branch.

[3] The first 2.5 kilometres of the line from the junction at Tinwald to the Frasers Road crossing survive as The Plains Vintage Railway & Historical Museum.