drip, drip, drip

We had a bit of a water issue in the basement. We'd cleaned up the puddle a couple times, but wasn't sure where exactly it was coming from. I assumed it was condensation-related from the A/C, but it's been nice here and the air hasn't been on recently. We both mopped up a lot of water before finding a small rubber tube that had been dislodged from the French drain. Tucking it back in place stopped the puddling on the floor, but there was still water dripping though the tube. It was an overflow for the humidifier that we never use. There's a spongy material that rotates through a plate of water that helps keep the air less dry in the winter when the heater is running all the time. However, we never use this -- and looking in there it's caked with mold and gunk. No thanks.

Even though we don't run this, it's still hooked up. There is a small copper tube that tabs a cold water pipe in the ceiling which was slowly feeding water into the humidifier. Of course, since it isn't running, it just drips in the plate and then overflows. Since the overflow tube on the floor was actually in the French drain until recently, I have no idea if this has always been dripping like this or not. But I almost have to believe it has been like this for a long time. Since we have very little water in the basement, the drains are just dry rock. So these drips just seep around the local area (far away from the sump area) and evaporate -- keeping the basement moist. But just how moist is the question because we do run two little de-humidifiers down there.

Watching the drips, I can ballpark their size and rate. I tried to make a similar size drop in the kitchen, but probably made it a bit smaller. I measured these at 9 drops to fill a 1/4 teaspoon measuring spoon, which is 1.25 ml. This comes out to 0.14 ml/drop, and looking at the relative sizes I think I'm underestimating the volume per drop. However, we can move forward with this value. For the rate, I figure it was about 1 to 2 drops per second. Again, estimating low, we'll go with 1 drop per second. Multiplying, 0.14 ml/drop * 1 drop/sec * 3600 sec/hr = 500 ml/hr. I have no good feel for milliliters per hour, so let's keep converting: 500 ml/hr * 24 hr/day = 12,000 ml/day. Sounds like a lot, but what is 12,000 ml? There are 3785.6ml/gal, so this turns out to 3.17 gallons/day. Wow.

I'm probably underestimating both the size and rate, but we're looking at 3 to 6 gallons per day dripping through this tube into the drains. The de-humidifiers in the basement are typically emptied once per day (though not regularly) and probably remove a combined 5 gallons per load. Which means we haven't been keeping up. So while the basement looks dry, it always feels moist and I finally know why.

I've turned off the valve now, reducing the drip rate to 0. I've also emptied the humidifier case so that even if it's still dripping a bit, it will take quite a while to refill to overflow. I have also emptied the de-humidifiers, and they are cranking away right now. I will empty them again tonight as well. By my calculations, there's probably a good bit of moisture still in the drains to take out, but staying on top of the de-humidifiers for 2 or 3 days may actually dry the basement out almost completely. Let's see.