The sump is around 6 ft to the left....no other check valve except right at the sump basin. City sewer here. Pretty sure it is 3 inch that it ties into.... Thanks for all he help!How far to the left is the sump?
Is there another check valve downstream of the point where the sink drain ties into the sump line?
What size piping does the sump line tie into ie the main drain?
Are you on a septic system of city sewer?
What color was Nepoleons white horse.....no that a different problem