# What is a good flow rate from a well?



## canfossi (Sep 18, 2005)

The people who are interested in buying my house want a flow rate done on my drilled well. Do a lot of people ask this when buying a house? I was wondering what a good average rate is (gpm)? Thanks Chris


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## agmantoo (May 23, 2003)

Anything above 3 GPM is adequate.


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## rambler (Jan 20, 2004)

Guess I'd want to know too, would not be uncommon to ask.

I live in a water area, so more than 10 gallons is fine, 20 or better is real good. Four is acceptable, under that will work for a house but it would be a bit limiting & would be a 'problem' here. In some arid parts of the SW, I understand 1/2g or 1 gal is fine, at least it's water where it is hard to get any at all.

So, it depends upon your location as to what is 'good' or 'bad'.

My well is officially rated at 20g/ minute, but when I had trouble last summer & the diggers were repairing it, found out it actually supplies 50g/ minute, but is limited to 20 because of the size of the pipe coming up.

--->Paul


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## Jessikate (Jun 9, 2003)

Here in Colorado it can range from 3-14 gpm. A wide range I know. Anything below 3 gpm and you will probably have to have a holding tank installed. Check with the company that drilled your well or your well permit and the gpm at driling should be listed - unless the Division of Water Resources in your area uses a "standard" form that states that pumping rates should not exceed a certain ammount.


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## cfabe (Feb 27, 2005)

For a family of 4 anything above 1gpm is probably usable with maybe a 500 gallon holding tanks and proper controls on the well to keep it from pumping dry. 1gpm is still 1440 gallons per day. As others have said for use without a holding tank you want 3-4 gpm. Note that this measurement is the recovery rate of the well, not the rating of the pump. In my area it varies widely, some areas you're lucky to get 2gpm, some are 20+.


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## Windy in Kansas (Jun 16, 2002)

So what is your flow rate? I assume you have at least used a five gallon bucket and done a timed test to see what it is? That will give a general rough idea.

Mine is 35 gpm.


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## cfabe (Feb 27, 2005)

Windy I would be interested to know how you measured your flow rate at 35gpm with a 5-gallon bucket.


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## jgbndaudio (Jan 26, 2005)

Hello,

My guess is that he filled the 5 gallon bucket in roughly 8.5 seconds. That would equate to roughly 35 gpm.




cfabe said:


> Windy I would be interested to know how you measured your flow rate at 35gpm with a 5-gallon bucket.


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## snoozy (May 10, 2002)

Mine is 12.5 gpm, which is considered by the county to be enough for 2 residences. If someone ever buys the land next to me, they might want to buy into my well (I placed it near that edge of the property for just that eventuality.) Since the price of drilling a well here has gone up from $12,500 to over $20,000, I could sell 'em a half share in the well for $10,000, thereby almost covering my whole expenditure on it while they save 50%. 

O' course, then I'd have neighbours right next door. Hmmn...


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## Hoop (Jan 1, 2003)

My well is 1/2 gpm. It is more than adequate for occupancy purposes. It is woefully inadequate for heavy lawn watering, irrigation, or stock watering purposes.

Here is why it is fully adequate for occupancy purposes. My well is 262 feet deep. 6" drilled well. 110 feet through sand & clay soils. The remainder through solid granite. The static water level is around 25 feet. This means the water will fill up approx 237 feet of casing. This is around 100 gallons, which is just like a resevoir.


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## SFM in KY (May 11, 2002)

The well we had drilled on the place in Wyoming was right at 3 gpm ... 400 feet deep ... and was adequate for house, plus livestock and small garden, windbreak trees, etc.

You couldn't turn it on full and get lots of pressure for watering a lawn but you could run it forever at just under 3 gpm ...


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## kmaproperties (Jul 6, 2005)

flow rate is not the issue.
static water level in the well and the recovery rate together make the difference.
static level is how much water is in the well casing when the well is not in use.
this is measured in gallons. the recovery rate is how many gpm the well makes when the pump starts drawing down.
all this said a low recovery rate ,say 2-3 gpm with a high static level will work.
however a low static level with 7 gpm can be a problem IE
shower 2.5 gpm
watering plants,washing car 5 gpm
flush toilet 2.5 gpm
dishwasher or clothes washer 3 gpm etc.
you draw down the static then use more than the recovery and the pump cavitates and no water till the static comes back up.
if you have 10-12 gallon recovery rate then you will be in great shape no matter what the static level is, hard to use more than that amount for an extendid time.
are the buyer city filks, most city folks are water wasters, because there is no limit on ther supply. we have had to school many city folks on how to use the well correctly and limit the number of users working at any one time.


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## arabian knight (Dec 19, 2005)

I don't believe that analogy at all that city Folk waste more water them County folk do. Heck I am on a well and I waste More water then Any city folk do I fill 3 1450 Gal tanks for my critters wash my cars I do not though water the lawn as I don't want to mow I would rather it burn up so I don;t have to mow. But I use water a lot I take VERY long showers. Even wash dishes under an open running facet wide open. I waste so much but I don';t care I don't PAY for the water as If I was Living in the city. So making that comparison I feel is unfair., When I did live in the city I used WAY less water because you HAVE TO PAY for it and the sewer,Because the amount of water used is also figured in how much the city charges for using the sewer system~! WAY too much money using lots of water if one lives in the city.. Water in the county other then using the electricity is basically free..ANd NO sewer charge at all~!!


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## MELOC (Sep 26, 2005)

think of it this way...the more you waste the more will flow in to the rivers and the city folk will have more water. :clap:


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## kmaproperties (Jul 6, 2005)

watering your critters is not wasting water. what i am talking about is watering a lawn and flowers every day. washing down driveways every weekend. kids running in sprinkelers every hot day. hosing down the roof to cool off the shingles !!! yes it happened. washing the siding down on a regular basis. filling 10 foot by 2 foot deep wading pools every day in the summer. washing small loads of clothes every day etc. 
I lived in a developement for many years, and this was the norm for most folks in the nieghborhood. keeping up with the jones' was more important than 50-100 bucks a month extra for water and sewer.


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## fantasymaker (Aug 28, 2005)

kmaproperties said:


> watering your critters is not wasting water. what i am talking about is watering a lawn and flowers every day. washing down driveways every weekend. kids running in sprinkelers every hot day. hosing down the roof to cool off the shingles !!! yes it happened. washing the siding down on a regular basis. filling 10 foot by 2 foot deep wading pools every day in the summer. washing small loads of clothes every day etc.
> I lived in a developement for many years, and this was the norm for most folks in the nieghborhood. keeping up with the jones' was more important than 50-100 bucks a month extra for water and sewer.


 Why wouldnt I want to do these things? seems like quite good Ideas. pretty lawn ,nice flowers, happy kids , more liveable house ,clean cloths ,whats wrong with these wonderfull things?
How can you waste water ? Doesnt it cycle?


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## dennisjp (Mar 3, 2006)

Windy in Kansas said:


> So what is your flow rate? I assume you have at least used a five gallon bucket and done a timed test to see what it is? That will give a general rough idea.
> 
> Mine is 35 gpm.


That will not give you an idea at all. I grew up drilling wells. When you hit the water vain, which sort of a small creek in the rock below the surffice dirt (which around here in Va. is usually 45' to 65' deep, before you hit rock) say you hit rock at 60' and drilled 125' total before you hit a vain of water. The pressure in the vain fills the well up somewhat. Acording to the lay of the land, I have had a 265' well fill up to within 25' of the ground level. We could bail it out fast enough to find out how much water was coming into it. That was with a churn drill type machine and not an air rig that is so popular today. They have pumps that will pull alot of water out, but on the well mentioned above, we were filling up 55 gal. drums in two to three minutes and the water level never changed. But what I was getting at, is that you can have several hundred gallons of storage in the well itself, before you ever get it down to where you can acually measure the amount coming into the well. A gallion a minute it plenty of water for any househould, "IF" there is enough storage in the well. With a small amount like this, you want to drill deeper to get that storage. A 6 5/8" ID well casing has a little over a gallion of storage for each foot of pipe. If you have a hundred feet of storage in the well and it is putting out a gallion a minute, it would take twenty minutes at five gallions per minute to take it out plus the well would have already supplied twenty more gallions during that time. Sometimes I get too technical, but that's me. sorry


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## rambler (Jan 20, 2004)

My numbrs way up above were the flow rates of the well - what it could put out for 24 hours straight.... As we see some of tese erms get interchanged & confusing.  Pulling out 5 gal or so only tests how big the pipe & pump are, you need to pump out for some time to empty the reserve in your casing pipe, and then seehow quickly water accumulates to get the flow rate.

When my well has issues, the screen filled up with deposits & plugged - could pump out 60 gallons as alwys, but after that the pump would suck air & very slow water flow. Perhaps I was down to 2 g/m flow through the plugged screen. After the acid bath they gave it, he could not pump my well empty with his sluce, which would be around a 50 g/m flow. However, my pump & pipe size 'only' allows about 20 g/m for me.

3-4 g is very doable, many livestock or watering large areas is questionable.

10-20 g is great for livestock, sprinkling, etc.

20-50 g is for many 100 head of livestock or the like.

1/2 - 1 g works in arid areas with holding tank & watching what your needs are, but you will be a bit limited in what you can do.

--->Paul


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## kmaproperties (Jul 6, 2005)

obviously you just want to be a pain here. point is when you have city water you can turn on every water using device in your house and never run dry.

with a well you need to run things based on your recovery rate and your available draw down. that is the point.

YES this is america and you can do whatever you want, and have everything as you stated, but in the country with a well you might need to space out your usage etc., that is the POINt I am making. this is not a spitting contest between your chip on the shoulder and the facts as I am trying to state them.
get over it.


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## Cabin Fever (May 10, 2002)

Just my 2Â¢ : There is a difference between the "flow rate" that a well can supply on a sustainable basis and what your particular well pump will supply. The amount of water that your well has a potential to supply is based on the geology of the aquifer it is finished in, the length of its well screen, the diameter of the well and the head of water above the well screen. The amount of water that your pump is capable of supplying is based on its horsepower, the diameter of the impeller, height of water it has to pump, diameter and friction loss of the supply line, etc. 

The point is, when we're talking about rating wells, there are two rates: the potential well supply rate and the pump's rate.


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## rambler (Jan 20, 2004)

Cabin Fever said:


> The point is, when we're talking about rating wells, there are two rates: the potential well supply rate and the pump's rate.



Which gives us:

Potential flow rate: How much water comes into the well if you remove it all. This is the good number to know, but typically was measured when the well was dug, and typically pumps & pipes are sized to deliver less than this number so one can't tell without an expensive test.

Actual flow rate: What your pump & pipe supply at maximum flow. Should be less than potential, or you will be starving your pump, adding air, & causing problems. This is the number you will likely get. To find it, need to pump water out for 1/2 hour or so steady, & then measure the flow rate - if you don't let the pump run full for a while, you may only be mesasuring the drawdown, not the actual steady flow.

Drawdown supply: How much water is sitting in the well casing pipe, which can be drawn out very quickly. But once empty, then the pump will draw air if the well itself can't resupply water that fast. This is important in slow-supplying wells (or shallow wells 3' across too), as mentioned by others.

--->Paul


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## TSYORK (Mar 16, 2006)

When I had mine drilled eight years ago, they went 175 feet and got 67 gpm.... Said I had enough to water the community.... PTL!


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## BoldtsWagon (Jul 19, 2005)

Out in the west with less than 7 inches of moisture per year (in the winter) you need 10 gallons per minute for every acre you want to farm or garden.


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## Windy in Kansas (Jun 16, 2002)

I stand corrected. I don't have any idea what the flow rate for my water well is.

I do know that after six hours of steadily pumping irrigation water my submersible pump will still put out 35 gallons per minute, measured by doing a timed test by redirecting water flow from my 2" line into three 5 gallon buckets.

The well does not "draw down" meaning it inflows as fast as my pump can remove 35 gpm. It has 85 feet of water in the casing before testing and during testing. The well has 5" casing if you are interested. I wish now that I had gone with 6".


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## rambler (Jan 20, 2004)

I am impressed they got a 2" pipe & a pump to handle that flow in a 5" casing.

Was common to put in 4" casing around here in years past, pumps were so tight fitting that often they stick in & the well is shot then. Dad for one of the few times spent extra & went for the 5 inch casing back then. 

--->Paul


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## BobK (Oct 28, 2004)

In some areas the time of year the pump test is done will influence output. One of the wells on our poperty was rated at 25 gallons per minute....based on the well log when it was drilled in Feb. That same well, driven 110 feet until it hit granite, in August will put out one quart per minute.....you need to be creative to get the most out of a well like that. This water was mostly 'groundwater' sitting on top of a big granite outcrop and it has lots of iron in it which is another pain to deal with. We later drilled a well 280 feet deep into the granite and hit some water, not much mind you, and this well produces 1/2-3/4 gpm no matter what the time of year it is....and it is nice clean iron free water! With proper storage, liquid level and pump controls we have no problem raising all the critters we want and as large a garden as we can handle for the two of us....unless you leave a faucet open then you start over!


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## Windy in Kansas (Jun 16, 2002)

I think that the line in the well holding the pump is 1 1/2" black polyethylene. It connects to a pitless adapter below the frost line. At the adapter on the outside of the well I connected to it with a 1 1/2" X 2" fitting. By using 2" line there is less friction loss in the piping which allows the pump easier pumping.

The pump is a Grundfos 1 horsepower unit with enough capacity to irrigate 50 rows of market garden crops at once with T-Tape drip irrigation. 

It has been awhile since I've actually market gardened. When I still planted I planted with rows 200' in length fed off of 2" pipe. T-Tape purchases were in 6,000' rolls yielding a cost of about 3 cents per foot plus fittings.

I hope this information isn't considered as hi-jacking the thread.


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## offGridNorthern (Jan 1, 2006)

canfossi said:


> The people who are interested in buying my house want a flow rate done on my drilled well. Do a lot of people ask this when buying a house? I was wondering what a good average rate is (gpm)? Thanks Chris


Chris -- in Ontario, this is one of the questions that buyers will ask. They may also ask you to get the water tested (shades of Walkerton, I guess). Don't let it put you off .... if they like the house a rate of 3 gallons won't put them off. Get it rated and assure them that it has been sufficient for your family's needs (assuming that it has). Don't lie ... if it's been aproblem, be upfront because they can come back at you for a number ofyears if it turns out that you deliberately misled the buyer.

My rate is 5 gal. a minute in a 126' drilled well.


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