Gresham and Troutdale grid
Gresham and Troutdale are Portland's two main suburbs to the East. Gresham is a big landhound and has gobbled up portions of Multnomah County that I believe rightfully belong to Portland. But I shan't go off on that. Their grid has been superimposed (more or less) on top of Portland's avenues. They have kept the avenue designation, but have named all the ones within their city limits. That is the explanation for the sporadic numbers next to some of the street names. Do keep in mind that Gresham's names run north/south, and their numbers east/west. Troutdale is much the same, but they throw designations to the wind.
One final note: These grids are to be used as interpretations only. Gresham is fairly loose in its grid structure, and Troutdale is even looser. I will not be held responsible if you use these grids as guides for navigation, however, I will take ALL credit if they work for you...
Note: italicized streets run along section lines