Help me use my 5,000 gallon cistern. Do I need a different pump?

I have a 5,000 gallon cistern that is probably 30 years old, it’s made out of concrete and is about 4\5ths full. I would like to attach a pump to a hose so I can water the garden, with it but the Marlow 1\4hp pump I have doesn’t do it. I tried priming it and attaching 200-ft of hose to it to get it from the cistern to the garden - 200’ away and up hill - and it did not work.

Is there something else [higher power] I can use? Anyone know about water pumps and what’s good or what’s bad? Anyone have a cistern? Is there something I could sink into the cistern? I really want that water and am not prepared to go back to little house on the prairie and carry bucket-fulls of water to the garden! :slight_smile:

Is the cistern under your house? or out in the yard? No suggestions for pumps, but if it has been sitting a long time and it is near anything structural, I would just leave it alone as I saw the aftermath of one that got emptied on accident under a house.

It is about 20 yards away from the house under it’s own small structure. Would really like to get a pump working in there…maybe even a hand pump, I am not sure.

Have you considered a submersible pump? They push the fluid to where you want it to go as opposed to pulling it.

Am I the only one who thought “Wow! That’s a LOT of breast milk!”???

In my experience pumps are not usually made to push a controllable amount of water for watering a garden usually they are always full on or off. Most folks I know with the same problem elevate a water tank near the garden to provide constant gravity fed pressure and then use a pump once in a while to fill the water tank.
If you want a portable pump look into fire fighting gear, a striker pump is a pretty easy to use 4-stroke motor, but you would still need a suction hose with a screen and a check valve or two
If you want a permanent hooked up electric pump, I can’t help you.

What is the approximate vertical distance from the top of the water in the cistern to the top of the hill? I am assuming that your pump is probably a centrifugal pump and while they can move a lot of water with minimal head pressure (like in a pool) their capacity drops off rapidly when trying to pump vertically.

I know a lot about pumps. I do wells and water pumps for a living. The questions you asking are very generic. In order to make a accurate recommendation I’d need very specific data.
How big a garden are you talking?
How much water do you plan on using/how much can your cistern system supply. What is the desired pressure.
Are you running a hose to a sprinkler?
Multiple sprinklers?
How much do you want to invest in a system?
How would you like to turn the water on and off?

Cheapest option is get a sump pump(like the style people use for basements) put a hose fitting on the output attach a hose and plug it in whenever you want water.

More expensive you could use a shallow well jet pump or submersible pump with a pressure tank allowing water whenever you turn the hose on.

Keep in mind in terms of outdoor watering 5000 gallons isn’t very much. You can easily empty that in an afternoon. So while it may be nice to size the pump so it blasts water out of the hose, you’ll find it pumped empty in no time.

The garden is a 12x12 raised bed garden, not small but not big either. The Cistern is almost full, and is a 5k gallon cistern. We only use the hose for watering the garden, we do not have a sprinkler system or anything like that. I don’t care how we turn the water on or off, but I like the idea of using a sump pump. How would that work exactly. The garden is about 150 feet away and approx. 20 ft in elevation gain from the cistern.

I doubt I’d go through 5k gallons in an afternoon, but I do understand it is not a lot of water…however, we get a lot of rain up here in the afternoon, I’d say 2-3 good storms per week.

Could I set a sump up in the tank, switch it on and feasibly use the hose? What would the pressure be like?

The pressure required is going to be the sum of the frictional losses plus the static head. The frictional losses are proportional to the flow and the pipe diameter. For example, 10 gallons per minute (gpm) through 100 feet of 3/4" hose will lose 14 pounds per square inch (psi) of pressure. If you reduce the hose size to 5/8" the pressure loss increases to 38 psi. Drop the hose size to 1/2" and you lose 120 psi. Your pump may be fine, but your hose may be too small. That’s what she said. Then there are net positive suction head requirements, already mentioned above when people discussed lift versus throw. We need more details. A pump curve would be nice.

a sump pump could cheaply move a large volume of water to near your garden. the sump pump would be immersed (lower end or all of it depending on design) in the cistern and a hose run to near garden. sump pump could fill an elevated tank (55 gal drum or barrel) and you could use that to drip irrigate your raised bed with a soaker hose (better for plants).

Hmm, I was using just a straight garden hose - you are saying if I want to pump it up hill I will need a heavier [thicker] hose?

I like the idea of a 55 gallon drum above the garden servicing a drip system. That would work nicely. And a regular sump would move the water from the cistern up to the drum? It wouldn’t have to be fast…just fillable.

you would have to see what the height the hose outlet could be at that distance. depends on the nature of the drip hose the bottom of the drum might work fine at the height of the bed.

if your total height is too much then you could fill barrels at intermediate distances sequentially to get the water the full distance.

The bed is on a considerable, south-facing, slope. So a drum at the top of the bed would drip nicely down a steep slope.

My main concern is getting the free, non-well water from the cistern up to the barrel without pretending this is little house on the prairie. Are you saying a direct hose from the sump, up to the drum would not work? It’s 135 feet from cistern to hose and 25 ft net elevation gain.

you just need to see what the pump you get can do. a sump pump can push water 135 feet horizontally and farther.

you might have to use two barrels and put one at an intermediate point and fill them sequentially.

I suggest running a 1" pvc pipe between the cistern pump and the garden, and just putting a threaded hose fitting on the end of the pipe so you can use a short hose at the garden. This will reduce the friction loss quite a bit. 3/4" pipe would probably be enough, but for a small project using 1" isn’t a huge increase in cost.

If you have a pump specialty shop where you live, you could check with them. They could provide a suitable pump.

Your other problem is running power and a switch to the pump.

Scanning quickly I couldn’t find the performance curves for any of the readily available sump pumps online.

Sump pumps in general do not produce very much pressure but can easily move large volumes of water. Their top end tends to be 30-40pse. In your case you don’t actually demand much pressure as you running an open hose which is 0psi.

The elevation isn’t very significant you are not losing much of anything to that. Even a small sump pump can throw 25 gallons a minute up 25 feet. For reference 10 gallons a minute out of a regular hose is pretty substantial.

Mentioned up thread is friction loss. That is your killer. A standard hose is 5/8 ID after 200 feet of that even a large pump is going to be a trickle.

Without numbers to work with I can’t guarantee anything. My suggestion based on experience would be this. Cost I’d estimate 275-325 dollars total
1HP sump pump.(aprox $200) You could go larger but beyond 1HP they get harder to find and less prices get steep.
1 1/4"x1" bushing
2 1" hose barbs
1 1"x3/4" reducing coupling
200feet 1" HDPE pipe(black plastic pipe, it comes in multiple pressure ratings get whatever is readily available to you, I use 160psi and 200psi. your local home improvement place probably carries 100-125 psi which is fine for what you are doing)
1 3/4"xhose adapter
2 1" pipe clamps
Teflon tape

Tools you’d need would be:
2 pipe wrenches
torch/heat gun (hair dryer or a zippo lighter would work fine for the lower PSI pipes)

Most sump pumps have an 1 1/4-1 1/2 discharge. Bushing that to 1 inch. Then thread a 1 inch hose bard(adapter.)

Roll out your pipe and attach one end to the sump pump. You are using 1 inch pipe because the friction loss on that is next to nothing for that distance. That pipe is cheap compared to industrial hoses you’d need for the larger diameter.

On the opposite end goes the other adapter coupled to the hose connection.

Then you can attach a short more flexible hose for your watering.

Sump pumps normally have an 8 foot cord. I’m guessing your cistern isn’t that deep but just in case ‘if your plugs underwater you’d need to look at changing something’. Shallower then that you are simply tossing the pump into the cistern with the pipe attached and plugging it in when you want water. If you want to be able to stop the flow of water by other means(like a spray nozzle on the hose) you’d need more to this.

That set up I’d expect the water to be flowing at a pretty comfortable rate. If it is sub par for any reason you could go to a barrel system like John has mentioned.

I found a guy in Denver who operates a used tool shop. He is going to trade me my 1\4 HP Marlow Centrifugal [circ. 1980] pump for a newer 2.5 HP submersible Sump Pump. I’ll have to add a bit to the trade, but they have one ready to go.
I am going to stop by the Habitat Re-Store and get the piping - they have the black piping for 25 bucks [400ft]. I love the habitat restore. And then to the hardware store for everything else.

I can’t thank you guys enough…this is great info boytyperanma, I appreciate your expertise…I am happy I also found some parts used as well.

The cistern is old, but I found out it’s bigger than I thought. The neighbor thinks it’s a 8,000 or 10,000 gallon cistern not five. It’s 10 foot deep by 6 foot wide cylinder, I am going to get the materials this weekend and I’ll post the results.

Thanks again!

I calculate that to be a little over 2,100 gallons.

I’m guessing at the depth…maybe it’s a lot more…I guess it definitely is if your calculations are right.