No, you would need two tunnels of about 9k each, one tunnel for the subway, another for the expressway. The boring device used for the A86 allowed for the dimensions shown below. Look, I'm not a civil engineer, but I think there might be something we can do here. Remember, the tolls on this system would be very expensive and I believe there would be a market for this option. Again, the toll highway doesn't replace any existing highway. It's an additional north-south route from Allen and Eglinton to about Front and Spadina. Yes, you also need exit ramps, and if eventually you want a replacement for the Gardner, you're going to need to connect with the western portion of the Gardner, probably along a Front St. extension west of Bathurst, perhaps running north under Niagara or Bathurst, and you would have to continue the tunnel to the DVP. Look, how do you expect to pay for anything? There are a few funding tools available: tolls, tax increment financing as land becomes available for development (for example, along land opened up by the removal of the Gardner), spectacles that provide private media coverage sponsorship such as the Olympics, or general tax revenues. The worst option, the one that doesn't include tolls or an Olympics, is the one that draws entirely on general tax revenues (bonds are the same as general tax revenues, but with interest). Within that worst category there are worse subcategories, i.e. the city picking up the entire bill! Look, we want use as much private financing as possible. Also, if we're going to draw from any tax revenues, let's try to share the funding with the province and the Feds. The problem is that the higher levels of government aren't always on board with what the city wants. We have a better chance of leveraging funding from higher levels of government through something like an Olympics, because our athletes represent regions across the country, obviously. Also, we want the fucking party, alright. Only a complete nihilist, bean-counting, joyless drone found nothing to celebrate in the Pan Am Games, and the same type of character will hate an Olympics.