Distribution Network Swabbing frequency

[oldmangiff]

Is there any general rules to how frequently Distribution Networks or Transmission Mains are Swabbed (cleaned) or is done on a case by case eg when flow rate drops, when consumers complain about colour etc.

How often are the utilities doing this in the US, UK or throughout Asia.

cheers

 

[ccor]

According to AWWA, "Most water utilities flush their distribution system pipes about once a year. Pipe flushing is done to improve water quality at the tap, exercise fire hydrants, uncover potential problems, and remove pipe tuberculation." Which is also consistent with my experience.