Sump pump basin dry

tallsamoan · 07-23-2011, 10:46 AM

Hi there,
bought the house last year and the sump pump appeared to work fine, it pumped every now and then after rainfall.
After a very harsh winter with lots of snow fall (and melt) and tremendous amount of rain this summer, the sump pump does not kick in. I checked the basin and it remains dry, standing water. I can manually start the pump without a problem.
The basement itself appears fine, it's dry.

What could be the issue with the basin not collecting water? Where does it go? What to look out for?

Appreciate assistance, thanks!

Daniel Holzman · 07-23-2011, 12:40 PM

I assume there is a typo in your post, do you mean to say there is "no standing water" in your basin? You do say the basin is dry.

The water level in your basin reflects the water table around the house. The water table around the house is controlled by the amount of rainfall you get, the type of soil you have, and the geometry of the surrounding areas. If you are not getting water in your sump pit, and the basement is dry, you are OK, and there is nothing to fix. As to where the groundwater goes, well groundwater moves downgradient, which usually (but not always) follows the slope of the land above. The speed that groundwater flows is controlled by the permeability of the soil, i.e. groundwater moves faster through gravel than through clay. It would take a PhD thesis, and enourmous amounts of money, to determine the exact path the groundwater flows from your house. I wouldn't worry about it, as long as the perimeter drain that collects the water and routes it to your sump was properly installed, you are fine.

tallsamoan · 07-23-2011, 07:57 PM

Quote:

Originally Posted by Daniel Holzman

I assume there is a typo in your post, do you mean to say there is "no standing water" in your basin? You do say the basin is dry.

The water level in your basin reflects the water table around the house. The water table around the house is controlled by the amount of rainfall you get, the type of soil you have, and the geometry of the surrounding areas. If you are not getting water in your sump pit, and the basement is dry, you are OK, and there is nothing to fix. As to where the groundwater goes, well groundwater moves downgradient, which usually (but not always) follows the slope of the land above. The speed that groundwater flows is controlled by the permeability of the soil, i.e. groundwater moves faster through gravel than through clay. It would take a PhD thesis, and enourmous amounts of money, to determine the exact path the groundwater flows from your house. I wouldn't worry about it, as long as the perimeter drain that collects the water and routes it to your sump was properly installed, you are fine.

Thanks Daniel, your explanation surely makes sense.
Yes, there are a couple of inches of standing water in the basin.
What baffles me that all houses around me (same height, basement & build and very close by) have the pumps running all the time. Also, we had 3 x the rainfall/ snow this year compared to last year and my basin was full (and pump going) all the time. This year the water seems to go elsewhere, although some neighbourhoods have severe flood problems.

imamomof4 · 09-27-2011, 09:44 AM

Quote:

Originally Posted by Daniel Holzman

The water level in your basin reflects the water table around the house. The water table around the house is controlled by the amount of rainfall you get, the type of soil you have, and the geometry of the surrounding areas. If you are not getting water in your sump pit, and the basement is dry, you are OK, and there is nothing to fix. As to where the groundwater goes, well groundwater moves downgradient, which usually (but not always) follows the slope of the land above. The speed that groundwater flows is controlled by the permeability of the soil, i.e. groundwater moves faster through gravel than through clay. It would take a PhD thesis, and enourmous amounts of money, to determine the exact path the groundwater flows from your house. I wouldn't worry about it, as long as the perimeter drain that collects the water and routes it to your sump was properly installed, you are fine.

We have a similar situation. Since the Aug. 23 Virginia earthquake - only a few inches of standing water in our usually very full sump pump basin. We also have a second sump well that feeds into the main well with the pump, but it is also almost dry. I'm in MD and we got a good shaking up from the quake and now I'm wondering if it could've changed the underground lay of the land enough to direct water away from our house and our perimeter drain. For the past 20+ yrs the sump pump has run nearly non-stop during rains. Heavy or sustained rainy periods required me to drop another pump in the basin and run a secondary drain hose out the basement window. It's always been a battle to keep the basement from flooding. Now nothing. Basement appears dry.

Should I be concerned about the perimeter drain possibly being clogged?
Thanks!