The safety upgrade will result in a slightly wider road cross-section and new guardrails will be installed in high-risk locations, which should reduce the severity of crashes, she said.
"By the end of the project there will be guardrails along almost 70 per cent of the route.
"While the work that we're about to do will improve the safety of everyone travelling on Dyers Pass Road, it will unfortunately cause significant disruption at times,'' said Ellis.
"For the safety of the crews working on the road, we ask that people biking or driving over Dyers Pass Road respect the traffic management that will be in place over the next few months as these safety improvements are carried out.
"There is not a lot of space for the crews to work in so at various times during construction we will be recommending that people travel via Lyttelton Tunnel or Gebbies Pass rather than on Dyers Pass Road."
The safety improvements are budgeted to cost about $7.2 million.
Waka Kotahi NZ Transport Agency is meeting three-quarters of the cost as it has included the project in its Safer Networks Programme.
Since 2008, there have been more than 270 crashes on Dyers Pass Rd, including several fatal incidents.
The work is expected to be finished in June next year.
