What water service pipe size?

[jdz]

im thinking of running a new line from the city supply as opposed to drilling a new well. The city line is about 3400’ from the house and about 325’ lower than my house. I believe my only option is for a 3/4” meter, I may be able to get 1.5” but that is a long shot. I’m sure I’m going to have to put a pump in somewhere along the line. I was hoping I might be able to get the water all the way up to my house and fill a tank with it then pump it from there. I’m looking for some advice on what size pipe I would need to run and also, does it matter what size meter I use?

 

[Terry]

3/4" is fine for the meter. That's a long run though. Friction loss is an issue and of course the elevation that you're dealing with. You would want at least a 1.5" line, and maybe more and then maybe some pumps?
How much do you save by not replacing the existing well?

 

[Sponsor]

 

[jdz]

My last well was over 20 grand and lasted 10 years with low yield, about 2 gpm. Don’t get me wrong, believe it or not with a storage tank, 2 gpm is plenty but I was thinking it may be cheaper in the long run to switch to city water. I can dig the trench and install the pipe myself.

By the way, I forgot to mention, water pressure at the street is 85-90 psi.

 

[Reach4]

I think you would want a multi-stage booster pump somewhat near the meter. Would you power that by running a wire, or get a separate electric service?

At current rates, what would your monthly water bill be?

 

[Sylvan]

City water you had better make sure you have nothing dripping as your paying for every drop you use

Also running up to 325 feet you will need a minimum pressure 141 PSI to get a trickle of water that high

Then there is the required pressure needed to overcome friction losses and what the min pressure you will need for showers , sprinklers etc

When doing high rise buildings we get the height of the upper most floor and times it by .433 to get the static pressure

In your case 325 feet X .433 = 140.75 PSI that is just static no flow

If you take 140.75 PSI times 2.31 you end up back to 325 feet and then we add in a fudge factor such as flushometers ned over 25 PSI and min for faucets is around 8 PSI

Do you have a hot water boiler? If so then you need to calculate the highest radiator / baseboard and make sure they have at least 4 PSI cold fill

A lot of localities frown upon a suction pump as it can draw water out of the city main especially when needed to fire fighting


Then there is the worry about possible frost line and velocity causing erosion in ferrous and non ferrous metal piping

85 PSI will only elevate water 196 feet

FYI 85 PSI = a velocity of 32 FPS (full flow)

Using 85 PSI and 11/2 pipe diameter would be 180 GPM (not including the pressure losses )

one cannot just arbitrarily pick a pipe size and then wonder about pressure tanks and what code officials might say as your so HIGH above the main I am sure they will want air gaps or the very least backflow prevention

 

[jdz]

The monthly bill won’t be bad. Most of the elevation (probably 150-200’) happens a few hundred feet from the house. If I had to, I would be able to get water into a storage tank near the bottom of the hill by the house and power a pump from the house there. The only backflow prevention required is a check valve at the meter.

I’m not too worried about how much pressure I will have, more about how far I can get the water without a pump.

I’m just looking at options at this point and want to know what I am in for either way, well or city water. So far, it doesn’t look much cheaper to go with city water than a well and I will have a monthly bill too.

 

[Sylvan]

" would be able to get water into a storage tank near the bottom of the hill"

Storing water can lead to bacteria growth as NYC is experiencing with tanks on the roof for the domestic water supply

In theory these water tanks save a fortune by allowing a small pump to supply the water to a storage tank above the roof but these tanks should be drain and cleaned once a year . They have to be protected from freezing
Either way you will have a pump but not all the other related required piping protection the city will require plus all backflow preventers have to be inspected yearly and tested in civilized areas