It will also build two viaducts - one 23m high and the other 17m - through stands of mature native bush.
A westbound bus route is planned from Hollyford Drive to Manukau via Redoubt Rd, as well as on-road cycle paths on both sides of the highway and a shared off-road bike and walkway all along the new highway.
Costs and a preferred route have yet to be indicated for a second stage of the highway, past Papakura to Drury, but Auckland Transport has indicated a 30-year envelope of $472 million for the combined work.
The number of full properties needed for the first stage is down from 113 indicated last year during a fiery round of meetings, including a large protest gathering organised by the Redoubt Ridge Environment Action Group.
Project director Theunis van Schalkwyk said yesterday the reduction followed route "refinement".
Most affected homes will be along the southern side of Redoubt Rd, but the group is upset Auckland Transport is sticking to a planned extension of Murphys Rd straight up the ridge and through a large colonial-style house with tall trees overlooking Flat Bush.
Environmental group chairman David Price said an earlier plan by Manukau City Council would have provided an easier "greenfields" ascent to the ridge without destroying its character and the home bought by new owners in 2011 on an assurance the property was safe from road-builders.
Mr van Schalkwyk said the project would cater for 4470 new houses in Flat Bush among up to 22,000 planned for an area reaching down to Drury and Wesley.
New industrial zones are also expected to provide 6000 jobs.
Renovations stopped
Eve Osborne says she and her husband Donald bought their home on Redoubt Rd in 2011 on an assurance the proposed road would steer clear of it.
Although they bought the house for close to $1 million, it was badly in need of renovations. But last year, these came to a dead halt with the house half finished when the Osbornes learned of a new plan to extend Murphys Rd straight up the ridge and through their property. That plan has now been confirmed although Auckland Transport has decided against buying homes each side of them.
"Our neighbours are going to be left on the edge of a ravine," said Mrs Osborne.
AT says an earlier plan would have affected more properties and an area identified for future housing.
Residents shocked
by Lincoln Tan
Redoubt Rd resident Vinny Parma said he was shocked after finding out his brand new house - due to be completed in two months - would have to go.
"From the discussions last year, they said they were just going to need the land right up to our fence so we went ahead to build the house," said Mr Parma, 28. "It's definitely a shock."
According to the plans, the eastern bypass would cut right through the property and Mr Parma said he was in a dilemma over what to do with his house.
His 53-year-old mother, Santosh Parma, who owns the house next door, said it was "absurd" the council had granted the consent to build the property.
"We have no idea who is issuing the consent and who is taking the land," said Mrs Parma, whose house will not be affected.
Raewyn Roberts, a resident since the 1970s, said if the plan was allowed to go ahead it would destroy what was left of a valuable ecological corridor.
She will be losing part of her front lawn and has made a 12-page submission to fight the proposal.
