Traffic Engineering Correspondence

3. Model Inputs

Table 1 identifies data inputs used in TTM’s traffic report as well as alternative values. The base and future
traffic volume estimations are generally based on information provided by DTMR provided in Attachment 2.

Table 1: Traffic Data Inputs and Alternate Values
                             TTM
 Input Data               Conservative           Source of Data Used           Alternate Data          Source of Alternate Data
                          Assessment
                                              Midpoint of 2015 DTMR
 Heavy Vehicle %               10%             Census Data and GHD                  8.49%              2015 DTMR Census Data
                                                 estimate of HV%
 Growth Rate –                               Growth rate 2014-2029 for                             Growth rate 2014-2029 for NB
 Northbound on                2.9%           NB off ramp in ‘do nothing’             1.7%           on ramp in ‘upgrade option’
 ramp                                                  case                                                     case
 Growth Rate –                               Growth rate 2014-2029 for                             Growth rate 2014-2029 for NB
 Northbound off               2.9%           NB off ramp in ‘do nothing’             2.8%           off ramp in ‘upgrade option’
 ramp                                                  case                                                      case
                                                                                                      Implied by ‘Design Future
                                                                                   18-31%
                                                Appendix A: 2009                                        AADT Volumes for ‘Do
                                                                                reduction on
                         See Figure 5.1      Representative Network                                    Nothing’ and ‘Upgrade
 Base Traffic                                                                      through
                         of TTM Traffic       Count for AM and PM                                     Option’ – See Table 5.1 of
 Volumes                                                                          volumes*
                             Report           Peak Hours of a Traffic                                    TTM Traffic Report*

                                                 Analysis Report                 Design 2014 Peak Hour Volumes for ‘Upgrade
                                                                                                   Option’
 Traffic Generation                                                                                    Empirical data from TTM
                         0.5vph/100m2         DTMR Warehouse Traffic             0.2-0.4vph/
 of Industrial Land                                                                                   surveys of other industrial
                              GFA                Generation Rate                 100m2 GFA
 Use                                                                                                       developments
 Fast food traffic                            DTMR traffic generation                               DTMR traffic generation rate
                             180vph                                                100vph
 generation                                    rate for a McDonalds                                   for a KFC/Red Rooster
                                                                                                     Suitable for complimentary
 Shared Trips                  0%                Conservative value                10-20%
                                                                                                                 Uses
* Table 5.1 of the TTM traffic report indicates Myall Street at Holts Road in 2014 in the ‘do nothing’ scenario could carry 5,114vpd
compared to 3,530vpd with the ‘upgrade option. This implies a 31% decrease in traffic on Myall Street at Holts Road in 2014 with the
Cooroy Interchange upgrade.
Table 5.1 also indicates that Myall Street east of Ferrells Road in 2014 could carry 10,290vpd compared to 8,468vpd from the 2015
census data. This an 18% decrease on Myall Street traffic from the 2014 estimations to surveyed 2015 data.
A reduction from base traffic volumes i.e. the ‘do nothing’ option is apparently. TTM attribute the reduction in volumes on Myall Street
to traffic redistributing as a result of the construction of the northern Cooroy Interchange with Elm Street (Cooroy Connection Road).
As such a minimum 18% reduction in base volumes is considered a valid outcome.