Exclusive King's College is one of three schools in the way of a route being considered for fast-tracking a $1 billion-plus freight-heavy road corridor through South Auckland.
The others are Otahuhu College and Sutton Park Primary School in Mangere East, where a community meeting tomorrow will oppose the plan - which could also affect more than 100 homes.
Auckland Transport says a new highway through Mangere and Otahuhu is one of four options it is considering after Prime Minister John Key's inclusion of an east-west link between the Southern and Southwestern Motorways and beyond in an $11 billion transport package.
Two other options include upgrading the existing route from Favona Rd to Mangere Rd and adding a new link from Otahuhu to East Tamaki and Pakuranga to the $1.5 billion Ameti roading and public transport projects begun from Glen Innes to Botany.
The remaining option - called Option 3 and likely to be preferred by businesses for its easier access to Tauranga's inland port and neighbouring industries - is a new highway running parallel to the Manukau Harbour's northern shore from Onehunga to Southdown and then to Pakuranga.
Auckland Mayor Len Brown has come out strongly against the Mangere-Otahuhu highway proposal, called Option 4, even though planners believe it would provide the most direct link from the airport to the East Tamaki industrial estate.
"It would seem a non-starter," he told the Herald. "What might look good on paper would be very difficult to deliver in terms of those communities, so let's stop wasting my time.
"My over-arching view would be that the best way to connect east to west would be to the north of the harbour."
A plan that Auckland Transport has shown local boards and businesses indicates Option 4 would run through King's College and Sutton Park Primary, and behind Otahuhu College. That school could also be affected by other options involving widening Mangere Rd.
The Otahuhu-Mangere Local Board has passed a resolution opposing Option 4 and asking Auckland Transport to consider other ways of removing freight traffic from local roads.
But some members are accusing the Mana Movement and its mayoral candidate, John Minto, of scaremongering by warning residents their homes could be bulldozed.
"This statement is dishonest and causing fear amongst our community," said board transport leader Lydia Sosene, who promised strong board opposition to Option 4, not least because "it comes right through my living room".
Mr Minto denies scaremongering, saying "the lines are on the map" and it was important for the community to mobilise early against Option 4.
King's College headmaster Bradley Fenner was unavailable for comment but Auckland Transport executive Rick Walden said work was at an early stage of comparing "high-level potential connections".
"The potential routes currently aren't well-defined - there is no certainty which properties or land may be affected."
Auckland Transport intends to consult the public next year on a preferred route, ready for construction to start in 2015-16 subject to funding and consents.