The news that the $1.25B Transmission Gully Highway in Wellington will not open on time because of the excessive "flushing" on the tarmac will come as a surprise to many Northlanders. After all, if excessive "flushing" is that big a problem, many Northland highways would be permanently closed.
Apparently, extensive parts of the new highway have bitumen seeping up through the top layer of chip seal, such that the road becomes slippery and sticky and car tyres end up pulling the bitumen further through the seal. That is "flushing". Eventually the seal comes off in strips causing "scabbing" - and we have plenty of that on Northland roads as well.
According to last week's NZ Herald report, much of the chip seal construction on the road was completed over winter in cool temperatures. To make sure the chips were able to bed into the bitumen, extra kerosene was added to the bitumen mix. This was to make it softer, allowing the chips to be absorbed by the bitumen during the cooler months when it would naturally harden. Unfortunately, when it warmed up again, the bitumen softened and seeped through the cracks causing "flushing".
It defies belief that a project almost $500 million over its original budget and two years behind schedule could be further delayed by six months, because the contractor stuffed up the final seal.
Still, it is better to get it right before traffic starts, rather than having to close the road again after it opens. Unfortunately, Northland roads have these continuous unsafe problems that we are forced to put up with, through continual lack of "fit for purpose" maintenance funding of our roads.
Flushing and scabbing give rise to lack of skid resistance and increased roughness for which Northland state highways have some of the worst measures in the country, and we have been a pilot area for regional speed limit reviews as a consequence.
In general, reviewing speed limits on state highways and local roads in Northland has been carried out in a spirit of community consultation with a professional planned approach.
It's hard though, to have a rational discussion about speed. Some people are in your face about the hoons that just roared past them on the road or past their gateway and narrowly missed a crash. Most of us see ourselves as above-average drivers who stick to the speed limit, and we yearn to see a speed camera around the corner as idiot drivers speed past.
Northland AA has submitted on all speed limit reviews over the past three years. It is generally accepted that 100km/h is not a safe and appropriate speed for most rural roads that are not state highways.
But in all speed limit reviews we need to adopt some non-negotiable principles:
• any new speed limit should closely match the operating speed of the road and make sense;
• our roads have a continuous programme of capital improvements;
• there is no trade-off between reduced speed limits and enhanced road maintenance;
• any new speed limits are well communicated with adequate enforcement and reasonable tolerance.
In identifying that the Northland speed limit reviews have been professional and well consulted, it is hugely disappointing to see the latest TV ad that the NZTA blurb says, "Aims to increase public awareness and understanding of the fact that some speed limits are no longer fit for the purpose".
It's been put to me that "Only the village idiot tries to explain what they are doing by yelling across a busy highway to a couple of kids who are intent on playing the fool beside a busy road while heavy vehicles are travelling past". I'm sure some marketing gurus will say, "Well that's the point".
Really! The ad is an insult to the intelligence of the average Kiwi and does nothing to enhance the reputation and professionalism of the agency that owns the roads and spends our money on them.
We are in holiday season. There should be no road works on our roads for the next three weeks. Road maintenance is at a standstill but we still need to drive carefully to the conditions and keep speeds down to the natural flow of the road. Safe driving and happy holidays.