A major road revamp has been announced for the stretch of highway between Hamilton and Tauranga, potentially reducing crashes by 70 per cent.

Transport Minister Simon Bridges announced today the proposed revamp of State Highway 1 between Cambridge and the SH29 turn off at Piarere. The preferred option was to transform the highway into a four-lane expressway for that stretch of road, effectively extending the southern end of the Waikato Expressway.

However, the NZ Transport Agency has stated more analysis and final approval was still needed.

Agency regional relationships director Parekawhia McLean said it was important to let people know of the early preference.


"We are telling people that a favoured option has emerged because a project of this scope and size affects many people who live, work, do business or travel through that part of the country," Ms McLean said.

"A lot of work still needs to be done, like further investigation, but we will be taking people along on this journey with us and keeping them informed along the way."

The number of deaths and serious injury crashes on the Cambridge to Piarere corridor is expected to reduce by more than 70 per cent through the improvements. Five people died and 14 were seriously injured in crashes on the route over the five years from 2011 to 2015.

Ms McLean said the favoured option would significantly improve safety by ensuring the road has the latest design and eliminating conflict between local traffic and state highway users.

The corridor will also improve the travel time, ensure the journey takes the same amount of time every time and improve access to places the community use.

Further detailed investigation and reporting now needs to be undertaken before the favoured option - known as E2 in the consultation phase - goes to the NZ Transport Agency board.

The final decision will be announced later this year.

Meanwhile, $8.1 million in short-term safety improvements get underway on the existing route late this year. These include a wide centre-line, roadside barriers at high-risk areas, upgraded signage and a right-turn bay into Keeley's Landing.