Work is under way on a $1.7 million realignment of State Highway 2 near Taneatua, while motorists using State Highway 30 should prepare for further disruption at Ruato Bay.
New Zealand Transport Agency Bay of Plenty state highways manager, Brett Gliddon, said the realignment of SH2 formed the second phase of the work to improve safety and maintain the security of an important regional freight route.
"By removing the curves, adding more road width and increasing site distances we expect to improve the safety of drivers along this section of the road."
The project involves removing the 85-year-old rail overbridge, upgrading the drainage system and realigning SH2 and Taneatua Rd.
Downer has been awarded the $1.7m project, with construction expected to take about five months. During that time the speed limit will be reduced to 30km/h at the site.
Mr Gliddon said State Highway 2 was an important local connector and regional freight route.
Meanwhile, State Highway 30 at Ruato Bay has re-opened to one lane a day earlier than planned following overnight closures.
Last week's closures were necessary so investigations could be carried out to help determine an effective solution to stabilise the rock face which collapsed last year.
"The investigation was a success and all the necessary drilling was completed over two nights a day earlier then expected. This was due to the safe and efficient work of the drilling team, and good weather," said Mr Gliddon.
The large drilling rig used reached up to 10 metres in depth, obtaining necessary information about the rock foundations below that will help with the design of the new road.
The next process is for the information to be used in developing the final design and then the works tendered to a contractor to carry out the repairs.
It is likely the construction work will require full closure of the highway, for periods during the day, over some weeks. The full closure will be necessary due to limited road and construction space. The permanent repairs are likely to be underway between late April and July and the road will remain a single lane with lights controlling traffic throughout that period.
Mr Gliddon said SH30 was an important link between Rotorua, Kawerau, Whakatane and the wider Eastern Bay of Plenty and was also a key heavy vehicle route to the Port of Tauranga.
Ensuring the security of this road was vital for the Bay of Plenty's economy, he said.
Motorists wanting to find out more about roadworks and detour routes can go to www.nzta.govt.nz/traffic/current-conditions or freephone 0800 4HIGHWAYS (0800 44 44 49).