20211104OBA_R2_Information_Request_Response - Acoustic RF · MCU21/0146

In terms of future potential traffic flows we note that a traffic study by Cardno for Noosa Civic extension
notes an overall peak hour increase of 42% which would result in 2,100 additional vehicles or 1.5dB(A) noise
increase compared to current scenarios without considering natural traffic changes occurring. It is noted
though, that the distribution of the traffic splits between surrounding roads. However, in the absence of
exact data we have applied such increase to the Hoffmann Drive daily traffic rates well.
In addition to the centre specific traffic increase, we note that the report indicates natural annual increase at
adjacent road networks. Ernie Creek-Hoffmann Drive intersection is shown to have average annual peak
hour movements decreasing, whereas the other access to Noosa Civic is predicted to have a 1.33% annual
increase. Furthermore, the traffic report shows a 0.8% annual growth for Noosa population, and due to other
intersection growths, adopts a 1.5% annual growth for all intersections. Based on this, our potential future
traffic noise increase relies on a 1.5% annual AADT increase for Hoffmann Drive, in addition to the 42%
increase due to the shopping centre, which would lead to an additional 803 vehicles in year 2031 compared
to year 2021.
Based on the above, our modelling of the future 2031 traffic scenario incorporated an additional 2,903
vehicles on Hoffmann Drive. This is a 60% increase compared to the 5,000 vpd used to validate the 2021
model. Such increase would result in a 1.7dB(A) additional increase in the noise levels of the validated 2021
noise model which itself predicted a 1.95dB(A) higher noise impact compared to the unattended noise
monitoring values.

Note, the recommendations in our previous assessment included a 3.0dB addition to the measured noise
levels to obtain year 2031 noise impacts, whereas the method above predicts year 2031 to have a 3.7dB
increase in noise impacts over the current measured levels. The acoustic report will be updated based on
the above and shall include the additional 0.7dB increase in noise impacts. Subsequently, the acoustic
treatment recommendations will be reviewed.

Refer to Section 5.1 of the revised acoustic report (ref: 20210208.3/2309A/R4/JJM, dated 23 September
2021).

Noosa Council Required Information
Item 15. Provide tabulated noise results at residential unit facades for day/Evening and Night periods.
Acoustic Logic Response
The revised acoustic report presented tabulated road traffic façade noise impacts for the requested periods.
Refer to Section 5.1 of the revised acoustic report.

Noosa Council Required Information
Item 16. Provide the required acoustic rating of façade elements to comply with road traffic noise for
day/evening and night periods to comply with the Table 10 Noise Limits
Acoustic Logic Response
Relevant sections of the revised acoustic report presented façade construction recommendations, including
acoustic ratings for glazing, walls, and roofs. Refer to Section 6 of the revised acoustic report.

Noosa Council Required Information
Item 17. Provide details on the inputs to the mechanical plant noise modelling including source sound power
levels and operating times for all plant items considered.
Acoustic Logic Response
The revised acoustic report presented mechanical plant noise modelling assumptions. This includes sound
power levels and operating times. Refer to Section 5.3 of the revised acoustic report. In addition to onsite
mechanical plant noise, we have also reviewed the Noosa Civic plant noise impacts and provided
recommendations to achieve compliance (Section 5.2).




 I:\Jobs\2021\20210208\20210208.3\20211104OBA_R2_Information_Request_Response.docx                            2