We have a ranch style house with a basement and overhead sewer. The house wastes (bathroom and kitchen) drain by gravity into the sewer lateral which is about 6 feet above the basement floor.
There's a sump in the basement laundry room that receives water from the drain tile surrounding the house.
The laundry sinks and the washing machine drain into a basin under the basement floor. That basin drains into the sump. When the sump fills to a certain level the pump automatically pumps the sump's contents up to the sewer lateral.
My wife complains that sometimes the sump has an offensive odor. I can't smell it because by olfactary apparatus isn't top shape, but visitors have said that from time to time they've smelled the odor, too.
We tried just running fresh water into the laundry tubs to sort of flush the basin and the sump, but that didn't help.
I dimly recall someone else having had this problem and someone suggested that bleach or some other chemical added to the sump now and then might help by destroying bacteria or other nasties growing in there.
The water column in the sump is about 5 feet deep and roughly 30 inches in diameter. If my high school geometry is holding me in good stead, that's about 24 cu. ft.
So what chemical, and how much might be a good dose for my smelly sump?
All suggestions welcome.
-Len