San Francisco, CA Open 4 months

Noise Issue

There has been a disruptive low toned generator or construction equipment for the past couple months at least. Today it is a rapid low bass, pulsating sound that began in the middle of the night and is still happening now. This sound has happened previously and turned into a more drawn out rhythmic pulse over time. The past week this near constant sound stopped but now the cycle seems to be starting again. If I stick my head out the window I can estimate it comes from downtown. Van ness?