Looking for some advice and feedback for configuration around a new well

[Gorf]

I've been reading a lot on the forum here and I've pulled together some thoughts for my well at a new site we are building on. Our well went to about 450 feet. We have clean water, but it's on the low-flow end of the spectrum. 4 -6 gpm. Consequently we are going to add in a larger holding tank. Maybe even a cistern in the future if we think we need it. For now it's just my wife and I. We don't have kids and so our water usage is pretty small. I've been monitoring our current water usage and it's pretty insignificant compared to our neighbors. The biggest thing we need to do is consider our sprinkler suppression system in the house. The well is in place and the pump is set so my questions are really about the post-well-pump part of the configuration.

My design starts by the well pump bringing up water, through a check valve (which eventually will add in a rain-water catch system that will have its own holding tank and filtration/treatment system. But that is for another day), and into a multistage filtration system. I would love if anyone could speak to recommendations. From the filtration system it flows out into holding tank. The holding tank is 500Gal but to be honest I might kick that up to more like 750 - 1000. From the bottom of the tank, it flows out to the booster pump. Given the grade difference between the house and the well, we estimate that we would boost to 80psi. On the pressure side of the booster pump I would have one or two bladder tanks to try to help offset the cycling of the booster pump. Then out to the house which is about 125 feet away and about 20 feed in elevation to the entrance and another 10 - 15 feet to the highest fixture in the house.

Ive got a lot of plumbing experience but I don't have any well experience. So any advice or feed back you all can provide will be 100% appreciated. Apologies that I banged out the drawing using a technical drawing tool. haha.

 

[Valveman]

35' extra elevation will require an extra 15 PSI. Standard is a 40/60 pressure switch. Adding 15-20 PSI would make it a 60/80 pressure switch. 80 PSI would require a 70/90 pressure switch, which is fine if you want extra pressure. But with a 60/80 switch, a strong constant 70 PSI from a Cycle Stop Valve will be 55 PSI constant on the upper floor. Constant 70 PSI pressure is so much stronger than an average 70 PSI when the pump is cycling on/off from 60 to 80, and the larger the tank the longer you will be at low pressure in the house.

With a 60/80 or a 70/90 switch setting you will need either a submersible or a multi-stage booster to make that much pressure. When using a Cycle Stop Valve to control the booster pump a 20 gallon size pressure tank is all that is needed, even with the high pressure.

 

[Sponsor]

 

[Reach4]

We have clean water, but it's on the low-flow end of the spectrum. 4 -6 gpm

Are you thinking that it would take about a minute to fill a 5 gallon bucket now? Or are you saying the well driller tested the well and says the well replenishes at about 5 gpm?

 

[Gorf]

35' extra elevation will require an extra 15 PSI. Standard is a 40/60 pressure switch. Adding 15-20 PSI would make it a 60/80 pressure switch. 80 PSI would require a 70/90 pressure switch, which is fine if you want extra pressure. But with a 60/80 switch, a strong constant 70 PSI from a Cycle Stop Valve will be 55 PSI constant on the upper floor. Constant 70 PSI pressure is so much stronger than an average 70 PSI when the pump is cycling on/off from 60 to 80, and the larger the tank the longer you will be at low pressure in the house.

With a 60/80 or a 70/90 switch setting you will need either a submersible or a multi-stage booster to make that much pressure. When using a Cycle Stop Valve to control the booster pump a 20 gallon size pressure tank is all that is needed, even with the high pressure.

View attachment 105435

Thanks for this! I think with a 500 gal tank, the In-tank submersed pump seems like the more ideal solution. Does that seem logical? Also, I have noted your comments about pressure. I will step back and target that 40-60 switch as you noted.

 

[Gorf]

Are you thinking that it would take about a minute to fill a 5 gallon bucket now? Or are you saying the well driller tested the well and says the well replenishes at about 5 gpm?

Actually that is a good question. Perhaps I am incorrectly interpreting what they told me. This is the pump test from the drilling company:

 

[Reach4]

This is the pump test from the drilling company:

That is a test of the well. They probably used a different pump than the one installed. That test does not describe a well that needs a holding tank and a pressure pump. Where did you get your "4 -6 gpm" figure? They pumped 12 or more gpm for 4 solid hours.

 

[Bannerman]

The well is in place and the pump is set

Is your installed submersible pump, the same one that is listed at the top of the well test report, or did the driller install a 1 HP 10 gpm pump for testing purposes only?

What brand and model is your actual installed submersible pump?

The diagram in your initial posting suggests, in addition to the check valve within the submersible pump, an external check valve may have been also installed, possibly located somewhere above the pump? Please clarify.

Your well report shows the water level was drawn down to 217'4" below the static level (= 245' total depth). Is that the depth where your pump was placed, or is your pump located at a further deeper depth within your 450' well?

What is the inside diameter of your well casing?

Pumping continuously at 16-12 GPM for 4 hours, caused your well's water level to drop 217'. Using an average of 14 gpm X 240 minutes = 3360 gallons, is a significant quantity which would normally exclude any further need for a cistern or additional storage tank.

Knowing the well diameter, pump placement depth, and the well's recovery rate, will assist to calculate the amount of water usually available in storage within the well casing above the pump. Knowing the well diameter and also knowing the well had recovered 42' within 5-minutes after water stopped being drawn, will be useful for calculating the recovery rate.

 

[Gorf]

They tested the well with the pump installed and in place. 6" casing. I guess it's actually 400' of casing and the pump is at 375'. So I guess I must have misunderstood what they said about the well. I'm glad you all could help me interpret that document. However, we have a specific code here in this part of the county that requires a cistern for water with a minimum of 400 gal for the fire suppression. It's extremely rural and a volunteer fire department. So there is some code we have to abide by to have a minimum amount of water in a tank/cistern. So, I'm kinda back to my original drawing a little bit:

Well pumps out and through the various filters and into the holding tank. Holding thank has it's own submersible pump that supplies the pressure to the house. The holding tank uses a float switch to refill from the well as needed as it's drawn down by the house pump. Based on comments above, given the height differential between the well and the highest fixtures, I'm targeting 40/60 pressure switch. Seems pretty straight forward.

 

[Reach4]

6-inch casing holes 1.496 gallons of water per foot.

However, we have a specific code here in this part of the county that requires a cistern for water with a minimum of 400 gal for the fire suppression. It's extremely rural and a volunteer fire department. So there is some code we have to abide by to have a minimum amount of water in a tank/cistern. So, I'm kinda back to my original drawing a little bit:

If you really have that correct, you could meet that by keeping a 400 gallon tank filled for fire.

If you pull your drinking water from that atmospheric container, you may have to chlorinate that container to keep bacteria down. If it is just for fire suppression, I think you would not.

But you may not understand the rule correctly.

 

[Bannerman]

At 1.496 gallons per foot within a 6" diameter casing, the water rise of 42' in 5-minutes, then equals a recovery rate of 12.56 gallons per minute while the water level is lowered to 245'.

The pump placed at 375' depth, will then result in approx 347' of water within the casing above the pump. At 1.496 gallons per foot, this then calculates to be 519 gallons of water stored and available within the well itself.

In addition, while water is being removed, water continues to refill the well at a considerable rate. This is why during the initial well test, pumping out 3300+ gallons over 4 hours, caused the water level to drop to only 245', which resulted in approx 130' continuing to remain above the pump.

we have a specific code here in this part of the county that requires a cistern for water with a minimum of 400 gal for the fire suppression.

Suggest reveiwing the exact wording of the code.

Your well itself has a storage capacity of over 500 gallons. Would the well's storage capacity alone statisfy the requirement for 400+ gallon availability for fire suppression?

Is water available from anywhere else, such as a pond or swimming pool, which the FD could draw water from? I anticipate 400 gallons, would be rapidly depleted.

If an additional cistern is required, how is that water to be made available? If the cistern is not required to be elevated to supply water by gravity, will the Fire dept need to connect their pumps directly to the cistern to pump out the water, or is only your pump expected to be utilized? If only your pump, how are you expected to ensure electrical power will be always available to operate the pump, especially as electrical service to the property will usually be cut-off by the FD when there is an actual fire.

Since a cistern would be utilized for both fire suppression and ongoing domestic water use, how are you expected to ensure the cistern will always contain the minimum required quantity of water?

To prevent the well pump from short cycling, the floats within a cistern will be typically adjusted to ensure the pump will run for a minimum required time. A 400 gallon cistern configured to cause the pump to operate once 50% of the cistern's capacity is depleted, will then contain somewhere between 200-400 gallons depending on when the pump last operated to fill it.

Well pumps out and through the various filters and into the holding tank.

In placing filters before the holding tank/cistern, what precautions have you taken to protect the well pump incase the filters become blocked with debris, thereby preventing water from entering the tank, and preventing the float switch from shutting off the pump?

The diagram in your initial posting suggests, in addition to the check valve within the submersible pump, an external check valve may have been also installed, possibly located somewhere above the pump? Please clarify.

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