“To keep the road performing well and reduce the likelihood of future potholes we need to make sure water can easily drain away from the hillside and the road and into the Mangawhero River.
“It’s also vital to have good drainage in the event of future flooding.”
Howie said residents and emergency vehicles would continue to have access while the road was closed.
“We looked at options other than daytime closures during this period, but the road is too narrow at this point to safely carry out the work under stop/go traffic management.
“In this case, a short-term closure is more efficient and less disruptive for road users.”
During the closure, a number of smaller works will be carried out on the closed section of the road, including felling unsafe trees.
“We appreciate these closures aren’t ideal and people travelling this section of SH4 have seen a lot of work in recent years, but we’ve worked closely with nearby schools, iwi and hapū around the closures to ensure disruption is minimal, by making the daily closure period as short as possible.
“Without this closure, the installation of the culverts would take a lot longer, delaying the overall project.”
The work is weather-dependent and may be postponed until the following week.
“Please plan your journey around these closure times and keep an eye on our Journey Planner for up-to-date information,”
Three new culverts will be laid across the road, and two existing culverts will be relined, to prevent surface water from eroding the re-built road or surroundings.
The project is part of wider work to restore full connection on SH4 between Whanganui and Raetihi following major flooding, which caused substantial damage to parts of the state highway in June 2015 and again in October 2019.