Rick Blaine wrote:
M Q wrote:
I assume that you meant to also include house 3 on option B.
No one seemed to ask:
Whoops. Yep - you are correct.
1) what is the expected flow rate of the pump? (at the anticipated pressure)
That I will have to see next time I climb down into the well house. That's
really the key question.
2) are the houses at the same elevation? If not, you are going to have far
more problem from that than from any slightly undersized pipe.
Yes, they are all approximately the same elevation.
3) What do you expect the demand from the houses to be?
There's little to no outdoor irrigation allowed, so it's household use only.
Worse case would be less than 10gpm per house I should think. The houses do have
active fire supression (sprinklers), though one wouldn't suspect more than one
house would be using them at a time. 
4) Is the entire 150' distance under the road. If not, you could
replace/augment the portion that is not under the road.
The road is only 30' across. The developer and his well company were OK with the
single line servering 3 houses and someone else here suggested that 5 could be
served off a 2" line if the pump would support it.
The combination of a 1.5" and a 2" pipe as in option A is
equivalent to just slightly under a 1.5" pipe for each house.
That is probably more than enough for most domestic uses unless you have
fire sprinklers or plan to do high volume outdoor irrigation.
We'll do some performance testing before accepting the house. It may be years
before the other two houses get built and we can deal with any problems then.
"...given that there is a single boost[er] pump supplying both lines and
the fitting on the pump is smaller than the larger line."
If I interpret this correctly, the system still has a single-point choke
point. Downstream of that increasing the line size or number of lines
can't help w/ what is an upstream restriction. Am I wrong?
The tank at the service end resolves the problem in that manner as long
as the total demand isn't greater than the tank capacity. Only place
that should be a problem would be perhaps in the event of the sprinklers
being in play, I would think.
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