It's an Expert submersible sump pump, models 116-122. They were at North Paulina St. in Chicago. No name plate that I could see on this thing. It's from before 1992. A humming noise, then silence, in our basement was the pump trying to start. Since it didn't and since we had very heavy rain a while ago I'm now wondering if we ever needed a pump in this 1964 house, built on clay. With my sump basin size, a measuring stick indicates a one gallon change and with flooding coming tonight I will be able to figure the GPM into the sump so I can size the pump. A reading every hour or so should be enough. My 5 gal. bucket rain gauge will tell how many inches we got. I figure I can plug the basin with a square gasketed plate and a weight on the plate, if need be. If the groundwater rises above the level of the top surface of the basement floor slab with the opening plugged, at what levels relative to the basement floor slab may I expect trouble? Should the pump I haven't gotten yet be set to turn on at the lower surface of the slab or the upper surface? Facts, opinions and hearsay welcome. . .