Auto roads are paid for, in part by gas taxes, but cyclists don't buy gas. So here's my idea: Sell sponsorships. You see this on traffic islands, and sections of highway. Why not have corporate or private sponsorship of a bike trail. In return, you put up a sign (make it tasteful) identifying the benefactor.
I watched an interesting PBS show recently (called "e2) talking about the bike sharing system that has been set up in Paris called "Velib". To help finance it, they put up signs that coul
d show advertising. They are small, only about a foot or so. It may be less than perfect, but it pays for the bike system which has changed the nature of the city of Paris. Watch e2 episode here.So you get corporate sponsorship to finance these new bikeways, and put up some signs. Be creative, and sensitive to the area, but give credit to the sponsors, and build more bikeways. Car drivers are happy, cyclists are happy, advertisers (I mean sponsors) are happy. Happy riding.