Where does the water come from in a sump pump hole?

At our parents’s house (built in 1962), the water that goes into the sump pump hole in the basement floor comes from the washing machine and utility sink when they are draining. Once the water gets to a certain level, the pump kicks on. The sink and washing machine are hooked up to the rest of the plumbing in the house.

I would suppose it depends on the house. My house is a cap-cod that was built on a slab in 1957 when it was common to sometimes lay the ductwork either under or actually in the slab. The sump pump housing is cement and most of the water that drains into is water that has leached into the duct work under the house and is draining out of a hole in the slab from there, from the ductwork. And thanks for reminding me. We are supposed to get 2–5 inches of rain tonight so I better go turn the pump on!

In your case I’m guessing foundation drains.

In most homes, when a sump pump is installed, it is installed along with a french drain (at least that’s what they call it around here). Essentially, they go through any concrete to dig a trench in the floor about a foot or two down all along the inside of the foundation. Into the hole they put gravel and usually a plastic pipe 3–4 inches in diameter. The pipe actually has holes all along its sides so the water from the foundation makes its way into the pit and into the pipe in that fashion. The ends of the pipe route around and end up dumping into the sump pump pit itself.

The pipe is sometimes fitted with a cloth sleeve, but not always, and is topped off with more gravel and fresh concrete on top of that. The sump pump pit is usually in a corner of the basement and is about 3 feet deep. From inside the sump pump pit you can actually see the pipes coming in from where they run parallel to the walls to drain the pipes. The pipes are usually fairly high up in the pit and the pump sits on the bottom to pump the water up and out and, presumably, away from your foundation.

Below.