The bridge is being pushed across the railway line using a specialised technique known as ‘‘incremental launching’’.

The completed bridge will have 16 segments, each about 22metres long and weighing 460tonnes. 

As a segment is completed the bridge is pushed further across the rail line – albeit at a speed too slow for passing motorists to notice – allowing for the next segment to be made in the space behind.

So far 10 of the 16 segments have been launched.

Bridge works will be finished by the end of the year, but  cars are unlikely to cross the South Coast rail line via the bridge until early next year.

Inspecting the work on Friday, Kiama MP Gareth Ward said the bridge building method was chosen to reduce the impact on the local community, traffic and the railway line, which are in a narrow corridor.

‘‘The first segment was launched from the southern end in late November last year and it is expected the last segment will be installed around the middle of this year, weather permitting,’’ Mr Ward said.

The bridge is part of the $329million Gerringong upgrade of the Princes Highway.

The Roads and Maritime Service has already been approached by people recommending names for the new bridge. An RMS spokeswoman said the suggestions would be passed on to Kiama Municipal Council’s street and reserve naming committee for comment.