The chairman of Avondale's community board and business association, Duncan McDonald, sounded definite. "They won't get a motorway," he said, "The people will lay down in front of bulldozers." The Government may have underestimated opposition to a motorway through Waterview to complete Auckland's western ring. Opponents may not be mollified by the partial tunnelling announced yesterday.

National certainly knows its decision against a fully underground connection has put paid to its prospects of taking the Mt Albert seat in the June 13 byelection.

Transport Minister Steven Joyce said: "We wouldn't be prepared to spend $1.5 billion to buy a byelection." His party probably also calculates that it now has a ready explanation for a loss it was likely to suffer anyway. In the absence of a local grievance, a byelection drubbing could suggest the gloss is wearing off the Government.

But it now runs the risk that the Waterview decision will damage the Government not just in the affected neighbourhood, but more generally. Motorways have divided many older Auckland communities, obliterating some. In most cases the damage was unavoidable; not this time.

There is a perfectly reasonable alternative route for the completion of the western ring. The road, already built from Manukau to Owairaka, could cross to the Rosebank Peninsula for the rest of its course to the Northwestern Motorway. The Rosebank route would be 2.5km longer than the 4.5km Waterview connection but it would cross industrial zones and mudflats, not a residential community.

The Rosebank route was favoured by the Auckland Regional Council and the Waitakere City Council, which represents those probably who will use the western ring most.

Yet the Transport Agency (previously Transit New Zealand) has been determined since 2002 to bring the ring into Waterview, and Rosebank was not one of the options reconsidered when Mr Joyce ordered a review of the tunnel proposal approved by the previous Government.

A six-lane tunnel estimated at $3.16 billion may be too much even for recessionary public spending. But people of Avondale, Waterview, Mt Albert and Pt Chevalier must be wondering why their interests rank lower than those of Freemans Bay.

Just last month, the Government agreed to a tunnel under Victoria Park for the northbound motorway lanes to the harbour bridge.

The cost of that cut-and-cover trench up to $430 million is to come from a $1 billion boost to transport spending to counter the recession. But it seems a needless extravagance for an inner-city sports ground that will still bear a flyover for southbound traffic. By comparison, the complete reconstruction of the much larger Newmarket Viaduct is expected to cost just $195 million.

Allocating road construction funds is an important and invidious task, best done at arms' length from politicians. It would be too easy to suggest the Government's different views of tunnels at Waterview and Victoria Park have something to do with its success last year in the Auckland Central electorate. But the residents of Waterview cannot be blamed for wondering.

To save their community now, they will need to act. Lying in front of bulldozers will be too late.

They need to enlist wider support to say "this far and no further" to motorway destruction of communities on the Auckland isthmus. If a tunnel is too expensive, there is an alternative to the west easily accessible from Pt Chevalier. Nothing would be lost by scrapping the Waterview route altogether, and a community could be kept intact.