Peter Koonce
In Portland, if it is something that needs to be addressed right away as an emergency (traffic signal flashing, immediate safety hazard, etc), use 503-823-1700. This goes right to the City's Dispatch and will be sent off to the appropriate party. Debris in the bike lane can also be called in there. The 823-SAFE line can take a few days, but definitely is appropriate for stop sign requests and other related elements that are described best here: https://www.portlandoregon.gov/transportation/article/299189
The PDX Reporter Ap is a nice way to send information to the City because it requires a photo (so staff know what they need to have when they arrive) and it is geolocated (your phone's GPS).
Best,
Peter