Took a drive through St. Helens yesterday and noticed that it appears either the city or county is trying to designate a "Business 30" route through town, using green Interstate Business Loop shields rather than the proper U.S. Highway shield with a "Business" banner.
There is absolutely no signage on U.S. 30 mainline to indicate that a business loop exists, so clearly ODOT is not involved here...
I just now looked at that on Street View (via ClassyGMap). I think it looks pretty cool, even if horrifically inaccurate.
Looks like the business route is signed to follow Gable Road, Old Portland Road, St. Helens Street, First Street, Columbia Boulevard, and St. Helens Street. While the business route follows two segments of St. Helens Street, the two segments are not one continuous street. My review of GSV seems to show signs for the counter-clockwise loop; I had difficulty finding it for the clockwise loop. Thanks for finding a previously unknown example of Business US 30 in Oregon. It is amusing that these might be the only Interstate business loop style signs anywhere in Oregon.
That's actually really cool. I added it to OpenStreetMap, and I am now trying to add it to Google Maps. I also put it on the Wikipedia "Bannered routes of U.S. Route 30" page.
Found one for visual reference: https://goo.gl/maps/HdJgdfPiw5p