Rerouting some defective sewer pipe to go straight into city sewer. The run is about 225 feet and I am replacing with 4" pvc. I am in the county so there are no regulations. How many trailers can I put on the 4" schedule 40 PVC before I have to run a second line? I would like to have only one sewer tap. Can it handle 6 trailers and 8 RV’s on one 4 inch PVC sewer run with plenty of fall? What are you running in your parks?