by Lindsay Shelton, October 11, 2016. Link here.
A report from the Wellington City Council identifies a “worst case scenario” if only trucks are used to carry the rocks needed to build a longer runway at Wellington Airport.
The report, prepared by the council for the airport’s resource consent application, says that 252 people sent submissions that were concerned about traffic during the four year construction period, and 202 people were concerned about noise.
The council report states:
The Project has the potential to generate adverse noise effects given the scale of works proposed, the duration of the construction project, and the proposed night-time construction works. In addition, the Project proposes road haulage of fill during off-peak periods (9.30am-2.30pm, and 10pm-6.00am) during weekdays, which will generate traffic noise effects on properties along the haulage route.
The applicant has provided a Construction Noise Assessment … which assesses the noise effects associated with constructing the runway extension, and the land-based transportation of construction materials (including fill) to the site. The report also identifies measures to mitigate such noise.
A noise expert has reviewed the airport’s proposal and has found that
The Project includes a construction duration of 48 months (or greater), and due to airport operations, construction will be focused at night when construction activity is usually avoided near residential activities.
The nearby residential properties on Moa Point Road will be significantly affected by the proposed night time construction noise (with noise levels of up to 14dB over the night limit of 45dBLAEQ), and some properties on Kekerenga and Ahuriri Streets to a lesser extent will also besignificantly affected (ie, up to 8dB over the night limit of 45dBLAEQ). The noise effects will have the potential to result in sleep disturbance and associated health issues for the residents of the Moa Point Road properties,and sleep impairment for the residents of some properties on Kekerenga and Ahuriri Streets.
There are limited opportunities for mitigation at source, namely onsite construction noise mitigation measures, or mitigation measures on public land.
The applicant has assessed the night truck movements in terms of traffic noise, and has established a programme of reduced truck numbers to keep the increase in noise emissions at an acceptable level. This approach is supported and would ensure truck noise does not become significant for neighbouring residents to the haul route.
The applicants’ noise assessment does not address the effects of the outbound day haulage route along Lyall Parade and Onepu Road. This is less likely to have significant effects given it’s during the day, but this assessment should still be undertaken to provide a clear understanding of the overall traffic noise
[A consultant] has identified that mitigation measures targeted at a set number of properties (on Moa Point Road, Kekerenga and Ahuriri Streets) are essential, and without this, the noise effects on occupants of these properties will be potentially significant. [He] further recommends that these mitigation measures be included as consent conditions. These proposed mitigation measures, such as relocation and acoustic insulation of properties, rely on the co-operation and permission of the property owners or occupiers.
…While these mitigation measures may significantly improve the impact of construction noise on these parties, there is no obligation for the owners or occupiers to accept alterations to their houses or to temporary relocation during the construction period. In the event that such measures are not accepted by them, there will remain a significant noise effect on these parties.
… it ultimately will depend on whether the applicant can manage to obtain agreement from these people for either mitigation option. If this cannot be
obtained, then there remains a significant construction noise effect, which will be unacceptable.
The council report also assesses the effect of construction traffic:
The worst case scenario is assessed from a traffic perspective, that being that all fill will be sourced from Kiwi Point and Horokiwi Quarries and transported to the site via road haulage. Therefore, the Council’s construction traffic assessment has been 2709846_2 based on road transport of all fill within the parameters (i.e. truck numbers, haulage routes, operating times, etc) proposed by the applicant.
The haulage traffic is likely to have the most discernible level of traffic effects given the overall volume of heavy trucks on the roading network where land based transportation of fill material is adopted (up to 620 daily truck movements/60 trucks per hour). The applicant has acknowledged these effects, and has proposed haulage routes and variable truck movements (i.e. differing truck numbers at different times of the day and week) to address them.
The proposed haulage traffic travel times avoid commuter and school traffic peaks, and weekends, which is appropriate.
The route selection, being predominately the state highway network with day time use of Lyall Parade and Onepu Road, is appropriate.
The use of high performance motor vehicles (HPMVs) is an appropriate choice of haulage vehicle i.e.it will minimise the total number of truck movements
Haulage via road is, from a traffic perspective, the worst case scenario. While the applicant has requested the worst case scenario be assessed as part of this application, this should be avoided if at all possible and should only be used if all other non-road based options are exhausted.
The report also states:
As already noted however in terms of noise, the proposed mitigation measures in the form of purchasing the affected properties, providing temporary re-housing during construction works, or providing acoustic insulation and mechanical ventilation rely on property owners or other occupants accepting these options.
Where this does not occur, the residents are exposed to some significant noise effects.
With respect to visual amenity, as outlined previously, the residents of Moa Point Road will experience the greatest level of visual amenity effects, which are unable to be mitigated. For the Moa Point residents it is unlikely that these objectives and policies will be met.