We bought a house last year that has a sump pump in the crawlspace basement. Having never had one before I tried to learn as much as a could about it so I could maintain it as needed. The pump cycles around the clock, sometimes there is only a few seconds between cycles if the ground is particularly saturated due to heavy rain. I can watch the sump basin fill up quickly in those cases. The fact that it is constantly cycling leads me to think it will burn out sooner than it would otherwise, and these pumps aren’t cheap to replace. I live right next to a canal off a large lake and the water table is normally only a few feet below the surface.
The sump pump currently sits tightly in what looks like a 5-gallon bucket with holes drilled in it. I was thinking that if I had a larger basin the pump wouldn’t have to cycle as much and the pump would last longer, but all the basins I’ve found are just deeper and not much bigger around. Having a deeper basin doesn’t really help since the pump sits on the bottom and there is a float on top. It will still cycle just as often. What I want is a basin that is the same depth as what I have now but a much larger diameter so it takes more water to fill it up to the level of the float, but they don’t seem to make such things.
Not sure if I would worry about it.
But if you wanted to increase the size of the sump you could look at an inground fish pond.
One of the things you should look at if what will happen if the pump should fail. If it is only a minor problem then ok, but if that could cause major damage I would either set up two pumps or have a back up pump on hand at all times. When I was working in buildings I never wanted a single pump sump. I change many a building and put in a second pump. And If I could not put a 2nd pump in then I made sure we had a portable pump that could be used in a emergency.
Get one that has the float on a vertical rod. It can be set to start when the water gets close to the top of the sump and then it pumps all the way down.
A good sump pump will last a long time but not forever so get your replacement pump now and have it ready when the current one breaks down in the middle of the night.
As stated above, use the kind where you can adjust the depth of the water before it cycles to keep it from running so often.
I think ‘sump basin’ usually refers to a container placed in what is often called a ‘sump hole’. The latter may seem redundant but I think the combination of parts make a ‘sump system’, so ‘sump hole’ is referring to a specific part of the system that could also be called the ‘sump sump’ if you want to be confusing about it.
If the pump is running nearly constantly (“only a few seconds between cycles”), that’s because the water inflow into the sump basin is just a little less than the pump’s output. Changing the size of the sump basin won’t change that. If it takes longer to fill the larger sump basin (because you’ve gone from a 5 gallon bucket to a 10 gallon bucket), it will also take longer for the pump to empty it (because you have to pump out 10 gallons, not 5). Changing the trigger levels also won’t change things. If water enters the basin at 2 gallons/min and the pump can put out 2.2 gallons/min, the pump has to run 90% of the time, whether that’s 9 seconds on/1 second off or 54 seconds on/6 seconds off or 21.6 hours on/2.4 hours off. So over time the pump runs the same amount whether it’s just taking the top inch off the water in the basin over and over and over, or emptying it completely each time it kicks on and waiting for it to refill all the way.
The only way to decrease the duty cycle of the pump when you can’t control the inflow of water is to install a pump with a greater capacity. Going from a pump that can put out 2.2 gallons/min to one that can pump 5 gallons/min in the scenario where input is 2 gallons/min means the new pump only runs 40% of the time, not 90% of the time.
In a worst-case scenario, where the water entry into the sump basin from the soil is the limiting step (ie there are no drain tiles entering the basin, and flow into the sump basin is rate-limited by the total cross section of the holes drilled into it), increasing the surface area of the sump basin will only increase the flow rate into the basin, and might be more than your sump pump can handle. That’s not likely to be the case, though.
It’s barely possible that you could decrease the pump duty cycle by allowing the water level in the sump basin to stay high, but that would only be true if the local water table falls right across your basin’s depth. What would happen if you turned the sump pump off completely? You said that the water table is only a few feet below ground. Would the water overflow the sump basin and fill the crawlspace, or would it stabilize at some level in the basin? Is the sump basin ever dry? The point of a sump pump isn’t really to run constantly because it’s been located below the local water table; at that point it’s a well pump.
Let’s make up numbers. If your sump basin goes down two feet , and the water table in dry conditions is one foot down, there will ‘want’ to be a foot of water in the sump all the time. Trying to pump this last foot of water out is a fool’s errand. When it rains, the water level rises temporarily, and you want to pump that water out, but not that last foot. In that scenario, you would actually be better served by a smaller sump basin that only goes down, say, 10 inches so it’s normally dry and only fills and gets emptied when the ground is saturated by rain.
We recently replaced the check valve with a new one that is silent because the thump thump of the old valve was keeping me awake at night. In order to change the valve we had to shut off the pump for a while and we watched the water get higher and higher in the basin… and then stop about an inch from the top. That tells me that the water table is about an inch below the basement floor, or at least was when we changed the valve. BTW, the basement floor is made up of loose rock covered in plastic sheeting.
Ok, check valve means water pumped out is not returning. 5 - 10 seconds is kind of fast, it can’t be getting a ton of water out. How far down does the water level go after 5 - 10 seconds? Pedestal pumps have a long rod with a float that can be adjusted up to a foot or more of depth before the pump starts up. The submersibles usually have a fixed depth setting which may not be very high. So more depth of water pumped out each time lengthens the cycle but the pump will be running for just as much time cumulatively, just fewer but longer bursts.
Where does your discharge go? If it’s not being run far away from your house, then the water being pumped out is just recycling into the ground and back into the sump, on an endless loop.
Man, if the water table is really an inch below the loose rock in your crawl space, then nothing is going to lessen the duty cycle of the sump pump other than raising it so that it only runs when there’s an inch of water on top of the plastic sheeting. Is the underside of that sheeting covered in condensation, by the way?
With the water table that high (or the house so low, depending on how you want to think about it), it probably doesn’t matter how far away they pump it.
Let me get this straight, you live in a sewer system, and you are glad about that?
Even if you had an ordinary house that was simply connected to a sewer system you might not be allowed to discharge a sump pump into it. An area with a lot of houses pumping sump water into the sewers could overwhelm that system easily.
Since, you did not answer my previous question, I’ll go with the data on hand.
Assuming a 5 gallon sump, and accounting for water level below the float, the pump is taking out about 4 gallons in 10 seconds. That gives a minimum capacity of the pump as 24 gallons per minute. The usual recommendation is 14 and 8 gallons per minute per 1000 sq ft of home, for sandy and clay soil respectively.
So I’ll first check the sq footage of your home and if it is around 2000 sq ft, the pump is good.
The rule of thumb is about 34 gallons per minute of inflow into the basin where you will go with a bigger basin. So if you tell the time between runs, I could do the calcs for you.
When we bought the house the inspector noticed that the previous owner had connected the discharge line to his sewer line, which is a no-no in our county. We had to have it routed out to the backyard, while presented it’s own challenges.