KEY POINTS:
I believe the Newmarket Viaduct will be replaced next year. How is it going to be built? Will a new bridge be built alongside the existing one, or the existing one replaced one direction at a time? Andrew Dronjak, Auckland.
The new viaduct will be built 13m to the east of the present one. It will start with four new southbound lanes, followed by the demolition of the existing three southbound lanes.
These will be replaced in the same spot by three new northbound lanes, allowing the rest of the old structure to be taken down.
The original date for construction to begin was 2009, but this has been brought forward because the consent process was less fraught than expected, so work should start next year.
The new structure will be designed to withstand a one-in-2500 years earthquake, which will make it considerably stronger and safer than the 1966 model we have now, which is a one-in-500 years job.
Q: For the past few months, Transit has blocked off the only passing lane on State Highway 1 out of Dome Valley heading south, with no apparent road works in sight. With heavy road usage, including trucks and campervans, this is not great, especially with the approaching holiday season. What is happening? Sue Langley, St Heliers.
A: Dome Valley is a notorious black spot, with 28 moderate to severe corners. Last year, the road averaged 11,000 vehicles a day, including logging and stock trucks, visitors unused to the road, holidaymakers and tourists.
Between 2002 and last year, 164 crashes were reported in the area, seven of them fatal.
As a result of surveys by various roading bodies, there have been some roadworks in the area to enhance safety, including road resurfacing, wider centre lines and edge lines, no passing lanes installed, and improvements to signs. And, as an extra precaution, the speed limit has been reduced to 80km/h.
Passing lanes are often closed when heavy traffic volumes are expected. Contrary to popular belief, they are often the cause of major snarl-ups, because the point at which the traffic merges becomes the slowest part of the road, causing major queues. When the passing lanes are closed, the traffic moves steadily, if somewhat sedately.
Q: I know that Transit and Rodney District Council have been evaluating the crossroads at Taupaki Rd and State Highway 16 in Kumeu for many years. My understanding is that a roundabout has been chosen as the best solution. But how much longer do we have to wait? There are frequent serious crashes at this corner, and already heavy congestion is aggravated when motorists are asked to use SH16 as an alternative to SH1 during holiday periods. Do we have to wait until someone is killed? Christine Smith, Taupaki.
A: Transit is working on a solution to the problems, but as the cheese ad says, these things take time. The issues must be closely studied, all options explored, the optimum solution must be selected (I'm paraphrasing Transit's response here) and only then can design and construction work begin. According to Land Transport New Zealand's website, construction should start next year, at a cost of about $500,000.
Q: The exit and entry driveways into Foodtown in Greenlane are separated by a tiny broken traffic island. Normally in the absence of a give way sign, the car turning right into the street has to give way to the car turning right out of the street. Does this apply to driveways, and if so does it also apply in instances such as the Foodtown one?
Paul Watkins, Auckland.
A. When is a driveway not a driveway? When it is the entrance or exit to or from a supermarket, is the answer.
According to the Road Code, if you are turning out of your own driveway at home, you give way to traffic on the road. But supermarket entrances and exits, as well as those at service stations, hospitals and the like, are counted as intersections, and different rules apply. If you are turning right at an intersection, you must give way to vehicles on your right that are turning right. So if you are on the right of the car turning from the street into the Foodtown carpark, he must give way to you.
* This is the last Ask Phoebe column for this year. I'll be back again on January 22.
