This afternoon, we did a small job while we had other family commitments to attend to, and enhanced the depth of the existing sump drainage hole in the middle of our concrete floor slab for removing rainwater falling inside our building.
We used our SDS drill machine to drill down another inch at the bottom of the hole and then chisel the lumps away to make a reasonable smooth bottom. But while trying to remove the buried original plastic foot (this held up the bucket during the floor slab pourings), the rest of the concrete down below started to break away so we had to remove all the concrete all the way down to the DPM layer.
We then mixed some fresh concrete with a high cement ratio and made it very dry so we could mould it into a neat flat bottom with vertical sides to fill in all the sides and hollows and make it waterproof again.
Upgraded-pump-sump
Now the water pump with its built-in automatic liquid level sensor will operate at a lower level in the sump hole and drain more water away from our concrete slab. We Hope! Grin!