Zenith is the flagship transport modelling package developed and used by VLC.

Zenith was first developed in 1995 by Mike Veitch , and has been in continuous development ever since. All of VLC’s current transport models are run using the Zenith package. VLC currently has models in South-East Queensland (including Brisbane), Sydney, Melbourne, Adelaide, and Perth.

Zenith models produce estimates of individual link flows for travel by private and public transport. For public transport services they provide boardings and alightings at individual stations or stops. These are available by time of day. Summary network performance indicators at a regional or sub-regional level are routinely available for:

• average trip distance (by mode);
• average trip time (by mode);
• market share (by mode);
• overall network volume/capacity ratio;
• average network speed;
• total travel distance (by mode);
• total travel time (by mode);
• value of time spent (by mode);
• consumer surplus estimates;
• total operating cost (by mode);
• cost recovery by public transport mode;
• crash costs; and
• pollutant emissions.

The development of Zenith has allowed VLC to develop models, which achieve unprecedented levels of accuracy. The development of these models has taken over 20 years, and has cost VLC millions of dollars. The result, however, is a product, which is world-class by all measures. In particular, its public transport models are by far the most advanced and accurate in the world, and have taken public transport modelling to a new level. Zenith’s recently developed toll modelling algorithms are at the cutting edge of world research, and are not available in any other software package. The modelling techniques developed by VLC have become industry standard, but no other organisation has been able to develop comparable models, largely because of the time, money and intellect required to create a piece of software as sophisticated as Zenith.

Zenith models have been used on an unprecedented number of major projects within Australia. A few are listed below:

• Integrated Travel Demand Forecasting for the Ipswich Motorway
• Melbourne City Link Demand and Toll Revenue Forecasting
• Townsville Port Access Impact Assessment Study
• Pacific Motorway Project
• Brisbane Port Motorway Project
• Inner City Bypass
• Gateway Bridge Duplication
• SEQ Integrated Regional Transport Plan (IRTP)
• Transport 2007
• South East Busway Operational Planning
• Petrie-Kippa Ring Transport Corridor
• Gold Coast Road Network Strategy Study
• Pine Rivers Transportation Study
• Redland Transportation Study
• Logan City Integrated Travel Forecasting Model Development
• Travel Demand Forecasting for the Lang Park Redevelopment
• Inner Northern Busway IAS
• Green Bridge Project
• SEQ2021
• Lane Cove Tunnel Audit
• Mitcham-Frankston Motorway Demand and Toll Revenue Forecasting

Because travel demand estimates are a key driver of transport infrastructure investment, they are (at the behest of Government, bankers, operators, infrastructure providers etc) often subject to independent audit.

In the context of several major infrastructure and planning studies, Zenith models have been reviewed and audited by the following independent modelling experts:

• Professor David Henscher:       University of NSW
• Professor Michael Taylor:         University of South Australia
• Dr David Ashley:                     (Sinclair Knight Merz)
• Fotios Spiridonos:                     Department of Infrastructure - Victoria