1960's house basement drain (s)
I have a 1960's (early) home with an unfinished, utility/storm basement which is 10' x 20'. I have owned the house for 8 months, and had a home inspection that did not find any problems with the plumbing. The water heater is located there as well as a furnace. There are two holes in the concrete floor, one has a float/ball valve in it. Where the furnace hoses run to. The other one is about 1 ft. up the grade and seems to hold water down about two inches from the cover/grate.
I have noticed a foul smell at times and recently after a large rain had an inch or so of water covering the floor.The water dissipated after about 4 hrs. and having a plumber snake the outside clean-out to the manhole 150' away.
The Plumber did not know what the second drain in the floor was for, and said I could fill it in with cement.
I started to get the water out with a sponge and small cup, took out a gallon and the water level did not change.
I then noticed a 3-4 inch pipe on each side of the standing water in the middle, like it was cut out or something.
I then had my wife flush the nearest toilet (upstairs) and I noticed the water level rise, or flow through the gap between the pipes or what looks to be a piece of pipe missing.
Is this some sort of vent that is allowing gases into the basement?
jp