3/4 water supply line - need to run another 120 ft to supply equine barn.

[TurboMan]

Adding an equine barn on our property. There is an existing pole barn which has a 3/4 copper supply coming into it. Water pressure is very good in the pole building. Need to supply the equine barn with good water pressure. Horses drink lots of water. The shortest run to the equine barn would be from the pole building with the 3/4 pipe.

New equine barn is 120 ft from the existing pole building and 200 ft from the house (supply)

Question: would I benefit by running a 1" or 1 1/4" copper pipe from the pole building to the equine barn? Would like to keep the pressure and volume as best as possible. Would rather not run a new line from the house to the barn. Septic tank is directly in line as well as irrigation lines and god knows what else.

 

[wwhitney]

Short answer:

Using 1" pipe instead of 3/4" pipe will reduce the pressure drop by a factor of about 4 on that 120' run. I.e. a 3/4" line to a barn 30 feet away should behave like a 1" line to a barn 120 feet away.

Long answer:

Will the new barn mean more water demand, or just moving water demand farther away? Will the new demand be at the same time as current demand? If you specify the maximum simultaneous demand rate at each building, and the pipe network lengths going back to the water main, and the water main pressure, and the minimum pressure desired at the fixture given those demands, then you can calculate the required pipe sizes for each pipe segment.

Cheers, Wayne

 

[Sponsor]

 

[Reach4]

As best as possible? You should be more practical. How many GPM?

100 horses each drinking 10 gallons per day could be supplied at 1 gpm to keep the trough full. https://www.menards.com/main/plumbi...8053-c-8672.htm?tid=812407089159389782&ipos=1
I don't know why these are on clearance, but there are others around.

So the flow rate would be more how much flow do you need to wash stuff down. Garden hose might do 5 gpm, but lets say 10 gpm for a heavy spray. A big pressure sprayer might be 5 gpm, but 1 or 2 gpm for the electrics.

Here is a simple calculator. http://irrigation.wsu.edu/Content/Calculators/General/Pipeline-Pressure-Loss.php

1 inch SIDR polyethylene pipe is more than 1 inch ID.

Using the calculator, it looks like 120 ft of 1 inch ID Pipe would drop 3.6 psi. Add maybe 2 more PSI for some joints etc.

https://www.menards.com/main/search.html?sf_categoryHierarchy=&search=sidr

 

[John Gayewski]

To answer the question yes you would benefit from running a 1.25" or 1" vs a 3/4

 

[TurboMan]

Thanks everyone. Will likely run 1 1/4" with sweeping 90's.

 

[Reach4]

Overkill won't hurt.

 

[TurboMan]

Getting ready to do this work this spring. As stated above there is a 3/4 copper pipe feeding the existing pole building. I need to go from this pole building to the new equine barn and was going to use 1 1/2 pipe. Could I put a 40 or 60 gal. expansion tank in the existing pole building to make up for the potential loss of volume from the 3/4 pipe? Would this actually work to increase the available volume? Is this a recommended practice for situations like this? I realize that if it did help it would be for a limited time until the tank refilled.

Was thinking I could pipe it without the expansion tank and if the volume is not adequate then add it - assuming it would actually help.

 

[Reach4]

A remote pressure tank is usually not a good idea. However if your usage is in bursts, it could be worthwhile. It will not help you when using water for several minutes.

If you wanted to supply a flushometer toilet, the extra pressure tank would be a big benefit.

If you do put in such a pressure tank, you would probably want to feed it through a check valve. That way there will not be the potential for an oscillation effect.