Construction of the $67 million motorway to Welcome Bay was unlikely to get under way for at least two years, spurring criticism about why it was being built in isolation from widening Turret Rd and 15th Ave.
The Bay of Plenty's latest roading plan showed that the huge cutting through Hairini, linking Welcome Bay Rd with the Hairini causeway, would begin in 2014.
But with the underpass timed to be built much earlier than the four-laning of Turret Rd and 15th Ave, there was concern the project would be compromised by morning rush-hour traffic creating a bottleneck at the Turret Rd bridge.
Welcome Bay city councillor Bill Grainger was frustrated that that the widening was not getting the same priority as the underpass. "I am annoyed, as others are."
Tauranga Mayor Stuart Crosby said that complicating the issue of the bottleneck at the bridge was the "high probability" that Turret Rd and 15th Ave would be returned to council ownership.
It was currently state highway.
He said if the corridor was redesignated as a local road, then the real issue for the council would be the high cost to widen the roads, even although about half the amount would be subsidised by the New Zealand Transport Agency (NZTA)
The removal of the roads' highway status traced back to a 2002 agreement between the council and Transit New Zealand - the predecessor of NZTA. It was the trade-off for Transit agreeing to build the new Harbour Bridge and making the bridge a state highway.
Mr Crosby said the council was in discussions with the NZTA on the phasing of the underpass with the widening of Turret Rd and 15th Ave.
An important element was a major Tauranga traffic study, now virtually finished.
Building the underpass without the road and bridge widening would only shift the problem for morning commuters coming from Welcome Bay. "The pinch point is clearly the bridge."
Mr Crosby said NZTA's key responsibility was the easy flow of traffic along highways. He believed that was why the underpass was the agency's priority because it removed cross-city traffic off State Highway 29.
The roading plan said NZTA's investment focus on the the underpass was "freight" whereas the focus for widening Turret Rd and 15th Ave was "connectivity".
"We know for a fact that the agency is stretched financially ... how that impacts on stage 3 of Hairini Link [the widening] has yet to be determined."
Mr Crosby said that despite the Government's $100 million commitment to the Hairini Link, he did not think that the underpass and the widening would be done together. Planning for the underpass was still around Haukore St and the intersection with Welcome Bay Rd. "The on-ramps and off-ramps are causing them some grief."
The Bay of Plenty Regional Council's 2012-15 land transport programme showed that $9.3 million would be spent from next year on property and design issues, leading up to the $57.6 million construction of the underpass in 2014-15.
The programme showed the four-lane project as being a priority in the 2012-22 10-year plan but not the first three years of the plan.
NZTA State Highway manager Brett Gliddon said the agency was still in the investigation stage for the underpass. After the final option had been confirmed, it would begin the consenting and designation phase.
The intention was for construction to begin in the 2014-15 year.