RFI - Attachment 1 - Traffic Engineering Response Letter

Information Request Item 3
Council Commentary
Provide additional detail validating the longitudinal grades at each approach to the proposed driveway
crossovers.

Modus Response
The longitudinal gradients adopted within the sight distance assessment have been determined with
reference to available Nearmap elevation and grade information, supplemented by the available site
survey data.

The assessment considers the longitudinal road grades on each approach to the proposed driveway
crossovers, with the adopted gradients determined over the relevant sections of Black Mountain
Range Road approaching the respective access locations.

To account for potential variations in the available elevation data, information from multiple Nearmap
survey periods has been reviewed, with the resulting grades compared against the available survey
information.

This comparison has been undertaken to confirm that the adopted longitudinal gradients are
reasonably representative of the existing road geometry, rather than relying solely on a single
elevation dataset.

Based on this assessment, the adopted longitudinal gradients are considered representative of the
existing road conditions and appropriate for the purpose of the sight distance assessment presented
in Appendix D.




Traffic Engineering Letter
220 Black Mountain Range Road, Black Mountain - 3 -