The $340 million project, which began in 2012 and was fully funded by the state government, has duplicated the Princes Highway to two lanes in each direction on the 7.5 kilometre section between Mt Pleasant and Toolijooa Road.

It includes two new interchanges with access to Gerringong and Gerroa, and the new Omega Bridge, which replaces the railway level crossing at Fern Street.

On Thursday morning, Parliamentary Secretary to the Premier for the Illawarra and South Coast and Kiama MP Gareth Ward joined Mr Baird and NSW Minister for Roads Duncan Gay for the opening of the Gerringong upgrade.

Throughout the dual lane, the majority of road will be 100km/hour, although the northern end will be 80km/hour to prepare motorists for the Kiama Bends. 

Mr Baird said it had been ‘‘a long journey’’ to see the project completed, but was now ‘‘good to go, and that is an exciting time for this community’’.

‘‘We said that we would upgrade the Princes Highway; this is the first part of a significant project and what it does, importantly, is it makes a difference to people’s lives,’’ he said.

‘‘This is a great case study in how we’re going to take Sydney forward, how we’re going to take NSW forward; the benefits here to the local community are clear.

‘‘On the way down, the Albion Park Rail bypass, we came through that... We are determined to deliver it, we will deliver it, and we know the difference that’s going to make when it’s done.’’

Mr Gay said this upgrade means ‘‘there is one less of those locations that banks up during the holiday period which can make us so angry’’.

“We’ve committed over $1.5 billion to the Princes Highway since coming to office and work on the next major section - the Foxground to Berry bypass - is well under way,’’ he said. 

‘‘There is no better sight than this road here today.

‘‘This is a project that the sun has shone on all the way through, even on those day after day of wet days that the project went through early in its genesis.’’

Mr Gay said his KPIs included ‘‘to finish it ahead of time, which we’ve got to’’.

‘‘I don’t think I’ve seen a more-loved project, of all the projects,’’ he said.

‘‘I’ve got 4600 projects across the state and this one stands out as a happy project that the sun has shone on all the way.’’

Mr Ward thanked the community for its patience.

“Having grown up in Gerringong and lived in this region my entire life, I am reminded all too frequently of accidents and injuries on the Princes Highway,’’ Mr Ward said.

“I am so proud of how Gerringong residents have embraced these works knowing that they will make our community a better and safer place.

‘‘There’s no doubt that there’s been congestion, there’s been difficulties while construction has been going on, but I think today everyone will agree that it’s been a little bit of short-term pain for enormous long-term gain.

‘‘What this will do is not only be a great investment for our community, relieving some of that congestion around Mount Pleasant at peak times, but also to provide the safer highway that will make a real difference in the lives of my community.’’

Kiama Mayor Brian Petschler said the works would signal an end to the ‘‘horrendous’’ traffic congestion the area typically encountered during each holiday period.