132003.221132 (23616DA) - Doonella Estate - Road Traffic Noise Assessment Report

5.2 Verification of Traffic Noise Model

The results of the noise survey carried out on 27 February 2004 at Location A have been used to
verify the road traffic noise model of Beckmans Road.

The road traffic noise model uses the year 2004 traffic flows, as stated in Table 5.1 and current road
alignment to determine the Ljo(18 hour). Table 5.2 compares the results obtained from the noise
survey to the predicted results from the computer model.

Table 5.2 Existing Noise Measurements and Predictions Lio(18 Hour)

 

Measured Lio(18 hour) | Predicted Lio(18 hour)
Site Location Noise Level dB(A) Noise Level dB(A)

 

A 69.9 70.9

 

 

 

 

 

Note: Both the noise !evel measurement and predictions are free field.

The road traffic model is considered to be satisfactory validated since the predicted level is within +
2.0 dB(A) of the measured level

5.3 Prediction Methods

The CoRTN road traffic noise model predicts either the Lio (1 hour) or the Lio (18 hour),

The current measured and predicted noise levels obtained at Location A have been used to calculate
the correction in dB(A), if required, for all allotments on the subject site. Since the predicted noise
level is above the measured noise level therefore the road traffic noise model is considered to be
predicting conservatively high. Therefore no correction would need to be applied.

The predicted maximum Leg {Ihour) daytime noise level is calculated based on the difference
between the measured Lio(|8hour) noise level and the measured maximum Leq (Ihour) daytime
noise level. The appropriate correction in dB(A) is applied to the predicted Lio(| 8hour) noise /evel
based on the difference in measured noise levels. A similar process is applied to predict the maximum
Leq (Ihour) night time noise level.

The predicted Lio(| 2hour) free field noise level for the park area is typically | dB(A) below the facade
corrected L10 (18 hour) noise level based on hourly traffic distribution.

Daytime is taken to be 6am to |Opm and night time |Opm to 6am.

5.4 Traffic Noise Predictions

The traffic noise model was used to predict noise levels on the subject site. PMM Group Pty Ltd
provided the Beckmans Road alignment.

3052R01V03.dac Proposed Residential Subdivision Beckmans Road. Tewantin Lensworth Lake Doonella Pty Ltd ¢/- PMM Group Pty Page 7

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