Water Storage Tank - Feedpipe
Water Storage Tank - Feedpipe
(OP)
Hi,
I am designing a new 500,000 Gallon Water storage and this tank is going to have a isoloated feedpipe coming in near the top of the tank and a discharge pipe located at the bottom of the tank.
My question is how high up on the tank are you suppose to put your feed pipe? I have heard 2/3 height of the tank or 10 feet from the top, but neither knew for sure they were just rules of thumb they had heard over the years.
If anyone knows I would appreciate any info.
Thanks
I am designing a new 500,000 Gallon Water storage and this tank is going to have a isoloated feedpipe coming in near the top of the tank and a discharge pipe located at the bottom of the tank.
My question is how high up on the tank are you suppose to put your feed pipe? I have heard 2/3 height of the tank or 10 feet from the top, but neither knew for sure they were just rules of thumb they had heard over the years.
If anyone knows I would appreciate any info.
Thanks





RE: Water Storage Tank - Feedpipe
Richard A. Cornelius, P.E.
WWW.amlinereast.com
RE: Water Storage Tank - Feedpipe
Currently the state of Texas requires an air gap in certain situations- usually when the tank is taking water from a wholesaler- but otherwise, it's not the general practice.
RE: Water Storage Tank - Feedpipe
It will also provide a method of reducing the amount of very old water
Hydrae
RE: Water Storage Tank - Feedpipe
I've also designed them with separate inlet/outlet pipes. This was done to improve the turnover in the tank as Hydrae mentioned. It was also done for tanks near the water supply to provide disinfection detention time. The height above the bottom of the bowl was determined by the detention needed.
I've never seen an inlet pipe located above the overflow however. In a sealed system, I don't really see what that will accomplish. I don't think there would be enough aeration to do any real treatment to the water.
RE: Water Storage Tank - Feedpipe
RE: Water Storage Tank - Feedpipe
RE: Water Storage Tank - Feedpipe
RE: Water Storage Tank - Feedpipe
Additionally, water can stratify in a tank, a common header/feeder does not provide mixing to prevent stagnant water. I seem to remember another post on this topic.
RE: Water Storage Tank - Feedpipe
In the interests of full disclosure, my recollection is that I saw this design idea in a manufacturer’s literature promoting the use of the product, rather than me using or reviewing it in an actual design. However, if the concept appears to address the needs in your application, it may be worth the time to verify its practicability.
RE: Water Storage Tank - Feedpipe
other issue is if the pumps can stand varying head? if you don't have VFD, and pumps are pumping mostly against static head, it is not vise to put inlet on the bottom because you will exceed max flow so you will have to throtle when the tank is empty.
i think this is where the 2/3H rule comes from.
RE: Water Storage Tank - Feedpipe
I saw several tanks constructed in this way.
RE: Water Storage Tank - Feedpipe
RE: Water Storage Tank - Feedpipe
CBI sells an internal eductor mixing device to assist tank turnover. The inlet flow to the tank through the eductor causes the tank contents to turn over.
RE: Water Storage Tank - Feedpipe
just calculate up to what height of the tank volume you would get 500000 gallons. simply place the feeder pipes up to that height. ussually there is free board if 1 to 1.5 feet left in the tank
regards
Rajeevalochana HN