My sump pumps discharge onto the lawn outside the house. I notice the grass there is very lush and green.
I have a feeling that the lush growth is due not just to the grass getting more water.
I think maybe it is due to the mineral content of the sump water.
I think maybe because the sump water has percolated through the soil, it has picked up minerals that are good for the grass, whereas rain water has no dissolved minerals.