J Acoustic Report · 132007.2398

                                                                                         ACOUSTICS & AIR QUALITY

The road traffic verification model uses the 2014 traffic flow, as stated in Section 6.2 and
current road alignment to determine the L10(18hour). Table 6.2 compares the results obtained
from the noise survey with the calculated results from the computer model.


Table 6.2 Existing and Calculated Road Traffic Noise Level

   Receptor Height             Measured Noise Level                  Calculated Noise Level
       metres                    L10(18 hour) dBA                       L10(18 hour) dBA
        1.3m                            55.9                                  56.8


The road traffic model is considered to be verified since the calculated level is within ± 2.0 dBA
of the measured level.


6.4   Calculations

The road traffic noise levels have been predicted for all retirement community allotments (refer
Figure 3.1 for numbering) and facade of the aged care building (refer Figure 3.2 for numbering).
The predicted Year 2024 L10(18hour) noise levels are listed in Table C.1.
From Table C.1 the highest predicted road traffic noise level is 71 dBA L10(18hour) in the
retirement community allotments and 66 dBA L10(18hour) outside the aged care building. All
other locations have lower levels of noise exposure. Based on the predicted noise levels the
MP4.4 Noise Categories in Table C.1 for road traffic noise are up to Noise Category 3.
The predicted L10(18hour) noise levels exceed the noise limits of 60 dBA (1m from the facade)
and 57 dBA (free-field) from Section 4.2.2, and therefore noise barriers are required. The
barriers required to achieve these criteria are 2.5m to 3.5m high as shown in Figure 6.1.
The predicted L10(18hour) noise levels with the proposed noise barriers are listed in Table D.1.
From Table D.1 the highest predicted road traffic noise level is 60 dBA L10(18hour) in the
retirement community allotments and 60 dBA L10(18hour) outside the aged care building. All
other locations have lower levels of noise exposure. The predicted L10(18hour) noise levels
comply with the noise limit of 60 dBA (1m from the facade) and 57 dBA (free-field) from Section
4.2.2 and therefore no additional noise barriers are required. Based on the predicted noise
levels the MP4.4 Noise Categories in Table D.1 for road traffic noise are up to Noise Category 1.
It is noted that the proposed noise barrier is very long and relatively high for what appears to be
a road carrying only minor to moderate traffic volumes. This is due in part to the strict noise
criterion being a quiet area, and the undulating terrain. It is noted that in the previous ASK
noise report for this site, the barrier height was restricted to 2.1m, resulting in higher noise
exposures at dwellings but accommodating this through more significant acoustic upgrades for
the dwellings. It is likely that any relaxation of the barrier height would require acceptance from
TMR and Council.
The noise barrier is mitigating noise from a TMR road and therefore it should comply with Main
Roads Technical Standard MRTS15 ‘Noise Fences’ dated April 2014. The noise barrier should
be solid and continuous with negligible holes or gaps, and achieve the TMR required density of
15 kg/m2.
A review of building construction requirements associated with the predicted MP4.4 noise
categories is included in Section 8.




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