The Cleanest and Dirtiest Cities

Cincinnati is ranked number 19 while Portland is number one. Portland is the 23rd biggest city while Cincinnati is right below that. Why then, there is such a huge gap on its effort to keep the cities clean and livable?

May be it's because Portland has a rail system and Cincinnati does not.

Rail system made a big difference in the day to day life of cities.
It means less pollution, less gas spent on the highways,
more space for parks and trees that helps clean the air,
more walkable places since people live around the transit system.
More efficient highways (only for trucks).
More efficient lives: no more wasting time on traffic jam.
More opportunities for people to work and access work:
it means more money
and more tax for cities to help keep the environment cleaner,
i.e. more money to run recycling program that reduce the number of landfills. Less landfill spaces means less health effects to communities.

One clear and simple act, but they still don't get it.