Newsletter #41 - 29 June 2017
We’ve secured a date to present our submission to Parliament’s Transport & Industrial Relations Committee in support of our petition. We will be flying to Wellington to present on Thursday 27 July 2017. If you would like to donate to fund this trip, please find details of how to at the end of this issue.
As you can imagine, this week’s issue takes on a nautical feel as we contemplate the upcoming race between hosting the America’s Cup and getting to the start line for the Hill Street intersection upgrade. It will be a nail biter!
MATCH THIS RACE
Yes, the America’s Cup is again New Zealand’s cup. If Auckland hosts the cup in four years, expect it to be held either at the beginning of 2021 or the end of 2021. Remember, when New Zealand won the Cup in May 1995, the next Louis Vuitton and America’s Cup series ran between October 1999 and March 2000.
So, what’s this got to do with the Hill Street intersection? Well, everything.
For a start, the Puhoi to Warkworth Motorway, the Matakana Link, and Western Collector are all expected to be completed by late 2021. Then, the Hill Street intersection upgrade will commence.
In the meantime, while America’s Cup boats are being built in the Woodcocks Industrial Estate, Warkworth will be at gridlock for most of the day. More than 2000 houses and several major roading projects will be under construction. Tradies will be squeezed into any available bach in the area. Add to that the tourists and refugees escaping central Auckland.
But what are the odds that the roads will be completed by the end of 2021?
Just how bad traffic congestion will be in 2021 before the planned roading projects will be completed has been difficult to grasp. We’ve been trying to figure out how we can best illustrate this.
Currently, the Annual Average Daily Traffic (AADT) that uses the intersection is 35,900, based on the period that data was collected. The daily or seasonal traffic might range from 25,000 to 50,000 vehicles per day.
Auckland Transport considers that the intersection is at capacity for most of the time in all directions. Based on the 2014 NZTA, the highest recorded peak traffic that can squeeze through the intersection is 2985 vehicles per hour. At that point, there are long queues in all directions. Since then, the 2014 improvements only added capacity of around 100-200 vehicles per hour.
According to the 2014 NZTA evidence, the capacity of Sandspit Road in 2009 approaching the intersection is between 390vph for morning peak and 560vph on Holiday End peak. This is consistent with the results of the November 2016 Elizabeth Street results, which the following charts show:
The main difference between 2009 and the 2016 trial is that Matakana Road traffic volumes have also increased, restricting Sandspit Road traffic at the intersection. The number of Sandspit Road vehicles being allowed to enter the intersection is consistently lower than 400vph.
When a road reaches capacity, queues form. Queues only shrink when there is a reduction in vehicles adding to the end of it. Based on the above diagram, the Sandspit Road traffic approaching the intersection with Matakana Road reached capacity 7am on weekdays and 9am on weekends and there was little queuing after 6pm.
We have said before that NZTA reckon that Sandspit Road traffic will double from 9000 to 18200 AADT by 2026. How is that even possible if the road is at capacity now?
So, by 2021, let’s say that Sandspit Road traffic will be 13,000 AADT and Matakana Road traffic will be 11,000 AADT. That would mean that queues on Sandspit Road would be at least 1km from 7:30am to 5:30pm and waiting times would be more than 20 minutes. These figures don’t take into account the courtesy levels of Matakana Road traffic to allow Sandspit Road to ‘merge like a zip.’
Traffic growth up until now has been 4-5% annually whereas Warkworth’s population growth has been 3%. Warkworth’s population is expected to growth by more than 10% annually. The NZTA, however, is still projecting that traffic growth at the Hill Street intersection will be only 1% up until the motorway, Matakana Link, and Western Collector are built.
By the end of 2021, Warkworth’s population would be double it is now. Traffic at the intersection will be around 40,000 AADT. Remember, that is an annual average. Think about what summer traffic will be like. Even if motorists spread out their commuter times, the intersection will be at capacity between 6:30am and 7:30pm most days. Every day will be like the 13-hour-long congestion on Waitangi Day experienced this year.
Here’s another thing. We know that the new zones will add a certain number of dwellings inside an expanding Warkworth urban boundary. But what about everywhere else?
One Warkworth has looked at the potential ‘in fill’ of potential housing inside the current urban boundary. Their thorough study shows that 3,770 houses could be built n