"Sustainable must also stand for financially self-sustainable and without taxpayer subsidies. Therefore sustainable communities must require only the users of alternative transport options to pay for those options such as bicycle infrastructure and streetcars."

I am going to have to disagree with you here. Taxpayer subsidies are needed to increase alternative transportation modes such as biking and mass transport.

With regional growth on the rise, our aging infrastructure is just going to get more congested.

What I think everyone needs to realize is:

Taxpayer subsidies used to educate citizens about the benefits of alternatives other than the automobile and the expansion of alternative mode infrastructure is the interest of everyone in the region.

To put it simply:

More people using alternative transportation modes = less people using cars = less congestion = cleaner environment, healither economy and more sustainable communities.