Judd:

Traffic projections were done initially by the proponent. They employed consultants to do this. They based it on historical records. From memory the traffic growth on the Sydney Harbour Bridge from the order of 1965 to about 1975 was about 3%. Then that falls off somewhat from there on to about 2%. The figures that the consultants came up with was for a traffic increase of about one and a half percent. Our people reviewed this. We slightly lowered what their projections were and at the moment the traffic projections that we are looking at now is approximately compounding at about the order of 1.2%.

Hensher:

The traffic projections were undertaken by the Roads and Traffic Authority based on data that was very very old indeed. In fact a lot of the data they used was something like 10 years old and they updated this with some most unusual assumptions like the growth in traffic, the assumptions on how operating costs increasing through time, how public transport fares are changing through time. These are all very important parameters. If one looks at the land-use strategies and the growth of jobs and so on, they are not taking place in the locations where this traffic is claimed to be going to. Where the growth is occuring is in directions that would not benefit someone who uses the Tunnel.

Neilson:

Our recent experience with our actual traffic as compared with our projections has not been very good. There has been less cross harbour traffic, particularly in the direction that's paying tolls than what we had projected and the reason for this I think is two-fold. One is that the resistance to paying a higher toll may have been higher than we expected. But I think more importantly is the general economic conditions and the price of petrol, the difficult times that we are experiencing at the moment.

Bathgate:

Remember they are long term forecasts. We're into the tunnel construction and these are predicated on close to a 35 year run so over the longer term some of those swings and bumps will probably even out.

Toon:

I think those projections were used because they supported the need for a tunnel.

Judd:

The overall benefit/cost ratios that were looked at for the Sydney Harbour Tunnel - in the EIS from memory I think the joint venture came up with a figure of 1.2. That was questioned, criticised by the Director of the DEP. They came up with figures that I've read through recently of about .78. We then carried out quite extensive benefit cost ratios ourselves and the sensitivity analysis that we did brought in figures between 1 and 1.5.

Smyth:

When the cost benefit analysis didn't produce a benefit that was high enough one of the variables, a key variable in the equation was actually doubled in its value. In that way the DMR managed to get a cost benefit analysis that looked respectable even if it left a lot to be desired.

Hensher:

Coincidentally at that time I had been asked, not by any of these organisations, but by the Victorian Roads and Traffic Authority, to provide some guidelines on the new dollar values that should be placed on travel time savings. I came up with a figure that was roughly twice what was currently in practice. Since something like 60-70% of time savings or should I say 60-70% of the benefits of road investments are time savings if you double your value of time savings you can have a major impact on the net benefit, the outcome that is. My figures were only suggestions but at the time Laurie Brereton who was the Minister for Roads, when he heard that my new values would actually double time savings benefits, it was suggested they use them. Consequently we noted a 70% increase in net benefits.

Bathgate:

The cost benefit ratio achieved, is it too low? I don't believe so, particularly taking into account the fact that this is not a project which is making a drain on the global borrowing facility of the State's finances.

Jones:

Well our findings for the Review Committee was that the initial marine biological work done did have some failings. Indeed they failed in fact to describe the environment which is one of the requirements for Environmental Impact Statements. For example, there was no direct studies and empirical data of the communities of animals that live on the bottom of the harbour where the Tunnel was to be built. So that there was dependence on work done further up the Harbour in different circumstances and we thought that was not really adequate.