I live in Wstchester County New York which is about 25 miles north of NYC. Last year I had sump pumps installed outside my home by the foundation. One side of the house is low lying therefore it takes on water that flows in that direction in addition to rainwater from the gutters. The other sump pump is in a 43 gallon tank burried about 2.5 feet below the ground and the exhaust pipe travels to the street. The incline to the street is uphill and therefore water remains in the pipe and freezes as far back to the check valve. In additions to any suggests you might have , what would the frost-line be in my area and would the PVC exhaust have to go below this line?Please understand that if the PVC has to be moved more than 1 foot below the ground,it has to come up that far in order to drain into the street. Look forward to hearing from you.