Apart from being aesthetically pleasing these things look like a joke! I can't imagine they actually serve any functional purpose except make the greenies feel warm and fuzzy inside.

I have several concerns with your approach in using these swales....
1. How are you protecting them from vandalism?
2. How will they survive in the dry summer months?
3. How much is the upkeep cost?

I think a much smarter approach would be to run all wastewater runoff through floating aquatic plants such as Eichhornia crassipes or water lettuce at a central location instead of maintaining all these individual swales. These aquatic plants are the best plant filters! They could live in greenhouses at this central location and a decomposition heat system could be used for heating in the winter months. Has anyone thought of a comprehensive "green" wastewater treatment system for Portland instead of this disingenuous "window dressing" approach?