A chance to take an up-close look at Tauranga's newest road was snapped up by more than 5000 people this weekend.
NZ Transport Agency project team leader John McCarthy said Sunday's open day was an opportunity for the public to view the progress and have the first chance to walk or ride through the underpass.
"It is an opportunity to give back to the community," McCarthy said, adding that the project has imposed on people's lives for the past two and a half years.
Once completed, the $45m Hairini Link project will provide a two-lane link underneath the Maungatapu roundabout.
The project aimed to improve people's journeys around the Maungatapu and Hairini roundabouts, separate state highway traffic and local traffic, and make travel safer for pedestrians and cyclists by providing shared paths.
"In the morning and evening peak time traffic was coming up from Welcome Bay, that traffic now will run underneath the state highway," McCarthy said.
"It should reduce traffic on State Highway 29 significantly."
McCarthy said the project was expected to be complete at the end of June.
He said the project had involved many different aspects including ensuring the Kaitemako Stream remained an available food source for hapu and iwi.
"There is a lot of fish spawning that goes on in that stream, so as part of the project we had to divert the stream and we relocated about 1200 fish during that process before we built a new culvert," McCarthy said.
"That culvert being a concrete base doesn't have a natural riverbed to it, so we had to put artificial fish passages that allow the fish to be able to travel back upstream for spawning."
An NZTA spokeswoman said more than 5000 people attended the community open day on Sunday.
Karen Vile lived in Judea and said she had cycled by the underpass a few times and had watched its progress.
"We are interested in riding the bike trails, there is never enough of those," she said.
Vile hoped the new underpass would help with traffic congestion.
Amanda Ottesen had cycled to the open day with her 4-year-old son to view the progress.
"We think it is going to be a lot safer for us to ride and I hope it will reduce traffic congestion," she said.
- 2500cu m concrete used in the structures (about 420 truck and trailer loads)
- The underpass is 120m long
- 210 concrete piles form the underpass walls which are 750mm diameter and 450mm apart
- 400 truck and trailer loads of earth removed from underpass
- 700 eels and banded kokopu were relocated from the site to the Te Pahou wetland
- 170,000cu m earth brought on site - 8500 truck loads
- 450 truck and trailer loads of sub-base and 300 truckloads of base course was used
- The asphalt is 45mm thick
- The 120m long underpass features a 2m high kowhaiwhai pattern named "Kai te mako" which was commissioned by NZTA and Nga Hapū o Ngāi Te Ahi, Ngāti He and Ngāti Ruahine.