Comment: Roads etc can be handled two things:

1) Temporary Apportioned Taxes on a State and Local Level

A proposal is put to the community for a temporary tax for a specific purpose. In this case: roads.

Once the road is funded and built, the tax expires

2) Limited Incorporation

It is my understanding that, before the middle of the 19th century, corporations were temporary entities that were formed for a specific purpose, then disbanded when the purpose was served.

Register a corporation(s) for building the road, bridges, support utilities - raise private investment capital (in addition or instead of) the public temporary apportioned taxes ..

.. then disband the corporation when the task is completed. So they can't cause any mischief.