No. The game is hardcoded to use the 'streets' systems, and no such checks and functions exist within the game engine. Once again, 16T never thought of that, and its their fault the game has so many issues modding. The game has pretty simple pathfinding. It takes a point and finds the nearest route. It does not and cannot be made to check for amounts of traffic. This same routefinding system is why the vehicles are so clunky when moving around civ cars. Switching lanes isnt possible due to how the streets system works and that having multiple instances of one lane can cause some weird issues when the vehicle turns left or right at intersections.
Besides what I and others have done for traffic AI, nothing further can be done to this aging, antique, argurably dead game.
User made scripts make the problem worse, by introducing stuff that runs checks constantly, thus making the game lag considerably on most low and mid level systems. The Germans pulled this off about 6 years ago, and even they couldnt get it right. All I've done was exploit the same move functions in the game as they did, and add my own idiot-proofing to the code. Turns out, nothing can be done in an FP setting, due to how many variables are in play. Number of emergency vehicles is one, another being road width, the civ vehicle width, number of civ vehicles, and how the game interprets the move command.