The population grew, and the roads could no longer support the capacity needed. Yes, government should fund it OUT OF EXISTING TAXES. More people = more revenue - what the fuck are they spending tax dollars on?
And as for "encouraging" - it's not government's job to tell people how to live, it's the people's job to tell the government how to work for THEM, the PEOPLE. You know, government OF the people BY the people and most importantly FOR the people.