Most cases if a tower goes down, Telus is usually aware of it pretty quick. Depending on what the problem is, and where the tower is, it may be fixed fairly fast or it may take time. (eg. tower in a city vs a rural tower) None of the telecom companies give status updates on small scale outages affecting an individual tower. If you're in an area with a tower sharing agreement your phone may just switch to the nearest other tower in range.
To report things, you could either contact support online or use the Telus Network Experience app.
There is also a chance it is not a real outage and is just a problem with your phone.
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