Washout limits access for residents, businesses on rural Whanganui road

A permanent fix for the Mangaiti Stream washout is going to take some time, Whanganui District Council senior roading engineer Brent Holmes says. Photo / Lewis Gardner

A second washout on Kauarapaoa Rd worries Whanganui resident Sid Soulsby because it will limit access for trucks moving logs off his property, Wairangi Station.

The road was closed by a washout the week before Christmas and reopened on December 23 but it closed again on December 28 after a deluge of rain caused more problems.

The winding gravel road connects with Rangitatau East Rd and State Highway 3 at Kai Iwi. It's had other access problems: the 2015 flood stopped residents getting to town for weeks.

The latest washout at the Whanganui end of Kauarapaoa Rd adds half an hour to Soulsby's trip to town, and a full hour for neighbours who live closer to the slip.

The washout has cancelled a Whanganui Summer Programme trip into the valley on January 8. Usually Soulsby provides a commentary to a busload of people during that trip.

Access may be limiting beekeepers too. The valley was "smothered" in thousands of hives, Soulsby said.

He hoped logging could resume on his property on January 17 because the weekly wages of 14 logging and roading workers depended on it.

For his own family, he wasn't concerned about the washout and restricted access.

Sid Soulsby and wife Christine run forestry, beekeeping and outdoor ventures in the remote Kauarapaoa Valley. Photo / NZME

"We've lived here a long time. We are a little bit used to it."

The washout could also hold up the Whanganui District Council's replacement of the road's Bridge 15, Erni's Bridge.

Funding has been agreed and the work was scheduled for the 2022-23 financial year. It will make the bridge strong enough for the heavier trucks that carry logging equipment. They have been using Rangitatau East Rd, which adds cost.

The Mangaiti Stream, 14km from Aramoho Cemetery on Papaiti Rd, washed out a culvert at the start of Kauarapaoa Rd in the week before Christmas. The volume of rain that fell made it a once in 250-year event.

The road was reinstated with a temporary fix and reopened on December 23. Whanganui District Council was unable to get the large metal box culvert that was needed and smaller pipes were used instead, senior roading engineer Brent Holmes said.

Another deluge put 90mm of water in the rain gauge of nearby resident Wendy Jackson on December 28, and the stream washed out the road again.

It was "West Coast-type rain" and very local. At Wairangi Station, 8km inland, there were only black clouds, Soulsby said.

"We aren't used to getting that much in a short time."

Access to Kauarapaoa Rd is closed, due to a washout. Photo / Lewis Gardner

The council will now do another temporary fix of the road.

A permanent one would take much longer, Holmes said. Waka Kotahi/NZ Transport Agency would have to be lobbied for funds, consultation with iwi done and design and consent approved.

The temporary fix will not be able to handle the logging trucks Soulsby hopes to get rolling on January 17. The alternative is to send them out on Rangitatau East Rd, and he's not sure how the economics of that stack up.

Rangitatau East Rd may need some work, and the trucks are likely to damage it. Most of the logs are heading to New Plymouth for export, so having them join SH3 at Kai Iwi rather than Whanganui could be a slight advantage.

Logging started at Wairangi Station in May 2019 and would continue for another two to three years, Soulsby said.

The station also harvests honey, runs some sheep and cattle and offers outdoor experiences as Wairangi Bow Hunting Adventures.