There is steady progress in the construction of the $25.8 million dollar Taramakau Bridge on the West Coast, between Greymouth and Hokitika.

The temporary platform used for the heavy cranes now extends across three quarters of the river as the main bridge piles of the new bridge are driven, extending from the Northern end.

The new concrete structure - between the existing road-rail bridge and the temporary crane bridge - will span 250 metres, rising 10 metres above the riverbed.

The old bridge will eventually be used solely for rail.