Detecting watering issues (broken pipe, etc.)

Could you please suggest some ways to use HA to help in detecting watering issues?

I have a flow rate sensor in front of pipes around my garden and I’d like to be alerted in case of any broken pipe, etc.

I see some scenarios but I’m not good enough in automation yet. If you point me into the right direction that help me a lot.

For instance, a simple alert to Telegram on huge water consumption at unexpected time.
I mean If a tap has broken or a fitting has come off on a pipe the flow rate will be much higher than during standard watering (hose).
At the same time, lawn watering also consumes a lot. So I need to have a calendar when high volume consumption is OK.

I can send message to Telegram (on hass start, for example). But I have no idea on how to create automation reading the file to take this schedule into account…

Well, at this moment I’ve created a simple sensor returning number of seconds since last flow update.
I use it to hide some charts (visibility) in 10 minutes after watering stops.

- platform: template
  sensors:
    caisson_time_since_water_pulses_change:
      friendly_name: "Time Since Caisson Water Pulses Change"
      value_template: >
        {% set last_changed = states.sensor.caisson_water_pulses.last_changed %}
        {% set now = now() %}
        {% set time_diff = now - last_changed %}
        {{ time_diff.total_seconds() | int }}
      unit_of_measurement: "seconds"
      icon_template: "mdi:clock-outline"

But how to alert when watering starts and continues with approximately the same flow rate for 5 minutes (but not immediately and not alert again and again)?

Any ideas highly appreciated.!