Tigard Police and fire use this system off the Washington County simulcast site #1:
Washington County / Clackamas County / Newberg Trunking System, Various, Oregon - Scanner Frequencies
TPD uses TG 60848 Washington County South Cities 1 for dispatch along with some other departments. The trunked system page also has some Tigard PD tactical talkgroups too. TPD unit numbers are 2000 series.
Tigard doesn't have its own fire department but is covered by a large fire department called Tualatin Valley Fire & Rescue. Station 35 covers Tigard.
You can listen to TVFR off the same Washington County Simulcast. TVFR is dispatched on 50640 Washington County Fire Dispatch and responds on 50512 Washington County Fire Ops 34 for routine calls and 50480 Ops 35 which is the county task force channel for structure fires, etc.