'Seamless' connection creates motorway bottleneck

Southbound traffic on SH1 is seriously delayed by merging vehicles from the new Southwestern Motorway connection. Photo / Supplied

It was meant to be a seamless motorway-to-motorway connection to reduce Auckland's reliance on State Highway 1.

Instead, the Transport Agency's $220 million link between the Southwestern and Southern Motorways at Manukau has many drivers seething as they inch nightly through a headache-inducing bottleneck.

Complaints from drivers held up on the Southern Motorway by others muscling in on a two-lane ramp from the Southwestern have forced the agency to change tactics while preparing to put traffic lights on what was designed as an obstacle-free link.

The new ramp signal lights will take up to three months to install.

Old-fashioned cones restricted the southwestern flow of traffic on Friday evening to just one lane.

But although that eased congestion on the Southern Motorway, it meant a slow crawl for traffic along most of the new 4.5km extension to the Southwestern, as the Herald found while driving both routes.

Traffic was unusually light from the Hobson St on-ramp to Highbrook on the Southern Motorway, where three lanes of stationary vehicles were backed up at 4.44pm.

It was a stop-start journey from there to the Takanini off-ramp, a distance of 10km which took 28 minutes via the Manukau interchange.

But that was an improvement on a 40-minute trip over the same distance reported on Wednesday night by Papakura commuter Richard Brown, who is furious the new connection was built without any money allocated to widening the motorway south of Manurewa.

"For all the smirking about the poor planning of the Delhi Games, nothing compares to the fiasco that is the southbound section of the Southern Motorway at Manukau," he said.

In comparison with what drivers had to ensure on the Southwestern on Friday, after the Transport Agency switched its traffic flow priorities, the Herald's trip along the Southern Motorway was a breeze.

Traffic was banked up along most of the 4.5km length of the new motorway extension from Puhinui Rd, a distance which took 23 minutes to cover between 5.37pm and 6pm.

Transport Agency spokesman Ewart Barnsley said that was the result of a "trade-off" between traffic flows on the two motorways, and he expected the cones to remain in place until the ramp signals were installed.

He said the agency's traffic management centre had reported "significantly improved" flows on the Southern Motorway, and hoped queuing on the Southwestern would ease with time.

But Mr Brown said nothing short of widening the Southern Motorway would ease the difficulties for commuters, and he was astounded the Transport Agency had not allocated any funds for such a project in its 10-year highway programme.

In the $1.75 billion Waterview Connection project the Northwestern Motorway will be widened between St Lukes and Te Atatu in time to cope with traffic flowing through tunnels under Mt Albert.

Although the new two-lane connection from the Southwestern joins three traffic lanes on the Southern Motorway, these reduce to two past the Hill Rd off-ramp at Manurewa.

Transport Agency highways manager Tommy Parker said last week that a plan to widen the motorway between there and Takanini, and then Papakura, could always be brought forward if necessary, and he pleaded for recognition of the benefits of the new connection at most times of day.

These include bypassing 12 sets of traffic lights along the old southwestern route via Wiri Station Rd.

Super City Mayor-elect Len Brown, who still has an office at Manukau City overlooking the traffic jams, has acknowledged concern about the new bottleneck.

"It's important to give traffic patterns a little time to settle down - however this does seem like a problem that could have been planned for," he said.

"One thing this does show is that building new roads is not the answer.

"Alongside roading projects, we need to unclog our motorway network with the public transport infrastructure I have been campaigning on."

FRIDAY NIGHT BLUES

Trip from Highbrook to Takanini on the Southern Motorway.
* Distance: 10km.
* Time taken: 28 minutes, from 4.44pm to 5.12pm.

Trip from Puhinui Rd to Manukau on the Southwestern Motorway.
* Distance: 4.5km.
* Time taken: 23 minutes, from 5.37pm to 6pm.