While I was initially conflicted upon hearing this, the more I think about it the more I feel that having two separate min. wages isn't a good idea. While the idea of helping deal with cost of living in Portland is noble, this doesn't help anyone who may live there but work outside the "Urban Growth Boundary" for instance. Similarly, as Nick mentions, this may also incite people to live outside the boundary and pursue jobs within and on the other hand, some businesses, if given the option, may elect to open up or relocate outside the boundary in order to avoid the higher minimum wage.