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Extending the runway: one truck every minute, for ten hours every day

by Lindsay Shelton
The brutal reality of constructing a longer runway at Wellington Airport is revealed in one of the 27 reports that were published this week. It provides startling details of the number of trucks-with-trailers that will be needed to carry rocks through the city for the reclamation – one every minute, for ten hours every weekday.

Starting at Ngauranga or Horokiwi, they’ll carry their loads on State Highway 1 through the city, for at least five months. State Highway 1 means that each truck and its trailer-load of rocks will go through the Terrace Tunnel and then along Vivian Street, Kent Terrace, and through Mt Victoria Tunnel. The report is written by a Christchurch company, who can’t have been aware of the mayhem that so many huge trucks will cause in these already over-loaded central streets.

The information is in a report about “construction noise,” [1] but it covers a much wider scope than just the noise:

There could be in the order of 300,000 CuM (cubic metre) of rock and Akmons, 120,000 CuM of stone, 1.1M CuM of general fill, and 75,000 CuM of granular pavement material, plus materials to make 7,000 CuM of concrete and 23,000 tonnes of bituminous surfacing material, which would need to be brought to the site on a regular basis over the [36 month] construction period. These materials would be conveyed to the construction site via a to-be-determined combination of land based and water based transport …

…The preferred [land] route is to use a ‘circular’ route with inbound materials being delivered to the construction site via SH1, Stewart Duff Drive through the airport precinct and on to Moa Point Road. The outbound route will continue northwards along Moa Point Road, Lyall Parade, Tirangi Road, Coutts Street, Bridge Street, Cairns Street, Ronotai Road, Jean Batten Street before joining on to SH1 via a left hand only intersection

Transportation of construction materials will occur Monday to Friday and will involve a 10 hour working day (0900h to 1500h, and 1800h to 2200h) on weekdays … The Traffic Design Group, transport consultants to WIAL, has estimated the average number of daily vehicle movements that would occur during the construction period. During peak periods of the construction programme, deliveries (truck and trailer unit) will not exceed 555 vehicles per day, or up to approximately 60 vehicles per hour …

…Transportation of materials via water based means is likely to include a fleet of bottom dump barges which will import reclamation fill from either a port, ‘borrow pit’ or via dredging and then transferred to the construction site or to a temporary staging pontoon/berth. The barges would operate on a revolving basis until such time that they can no longer float over the rock dyke…For the purposes of this assessment it has been assumed that there are an estimated six deliveries by barge per day (i.e. 12 two-way movements).

Then there’s the noise – which will be heard at night, during the curfew.

Certain activities during airport operating hours could pose a flight safety risk because of the height and / or proximity of the operations to the main runway. Because of these operational restrictions, certain construction activities would have to occur when the night time noise curfew is in place. During this curfew period, ambient noise levels from the airport and other sources of noise will be at their lowest and any night time works may have the potential to increase the likelihood of disturbance to residents near the airport.

Many of the construction activities would produce noise of a magnitude lower than airport noise during airport operating hours. However, during the night time curfew period of 0100h-0600h when the airport is closed for scheduled aircraft movements during which certain activities will be undertaken due to operational restrictions, construction noise would be significant without appropriate management and operational controls. The principle contractor will be required to prepare and operate under a Construction Noise and Vibration Management Plan and a Construction Environment Management Plan, which will include predictions of construction noise and identifying necessary mitigation measures…

There’s much more for the locals, and the contractors, to worry about, if the proposal gets resource consent and if the airport succeeds in finding the money.

There are 4 main (inter-related) constraints associated with the project:

Building the project at an operating airport …which is located in a fairly densely developed urban/suburban environment.

The weather and sea conditions in Lyall Bay.

The logistics associated with moving and placing a large quantity of bulk material.

The use of specialist plant to facilitate the reclamation works

There’ll be worries for pilots too.

The Obstacle Limitation Surface is one of the most significant constraints for the project. The OLS defines the surfaces in the airspace above and adjacent to the airport. The OLS is necessary to enable aircraft to maintain a satisfactory level of safety while manoeuvring at low altitude in the vicinity of the runway. These surfaces should be free of obstacles and are subject to controls such as the establishment of zones, where the erection of buildings, masts, and so on, that may penetrate the OLS are prohibited. These restrictions also apply to temporary structures such as construction works, e.g. use of cranes, towers etc.

And finally, the report helpfully defines “noise,” thereby forewarning the airport’s neighbours of what could be in store for them.

Excessive noise can interfere with speech communication; it can interrupt a wide range of different types of work, particularly activities requiring sustained concentration; it can disturb rest and relaxation; and depending on the hours of operations it can disrupt normal patterns of sleep. Continuous high noise levels for extended periods of time can contribute to noise induced hearing loss, whilst at the generally lower sound levels typically found outside houses, residents often report varying degrees of annoyance. The World Health Organisation (WHO)defines noise annoyance as ‘a feeling of displeasure evoked by a noise’

But worse than the noise, think of all those trucks – one every sixty seconds.