Flushing the waterpipes of a four story building

[tabtech]

I am looking after a building and there are slightly elevated levels of Aluminum (.17 mg/L) and iron (.326mg/L).
Out turbidity levels are approx 5 times the standard ...currently measured at 1.7 NTU's.
Source water is pretty clean with no elevated metals.
I have been asked to submit a flushing recommendation.
Should I flush and take samples by floor to source the iron and aluminium.
What is recommended flush times with different size pipes?
I have been unable to find much info on the internet.

thanks, Tom

 

[PEDARRIN2]

In new buildings we typically require that all strainer screens and/or faucet aerators be removed, cleaned, and replaced prior to flushing.

We do not require a set period, but I would suggest about 10 minutes with all faucets open. Flush the toilets/urinals at least 3 or four times to flush the piping to them.

Prior to that, you should drain and refill the hot water heater.

After that, I would take a sample at each floor - from the sink. I am not sure where you would be getting aluminum since I am not aware of that being used in domestic water piping or equipment. The iron could be from piping - if the building is older and uses galvanized pipe.

That is a start.