I am running a return line from my garage to the house. I have two questions.
My returns in the house is in the craw space under the house. I am running the line from the garage (50Ft ) to the house. There is an elevation difference of 3 feet to connnect to the house. Since I will be running this for the washer and a utility sink only. Can I use a pump to push the water up when I run the washer or sink to push the water into the house drain system?

Second will I need to vent it at the garage only or will if need a second vent along the line.

The goal is to just push the water up in to the house lines.

Thank you in advance

Luigi

So the garage is 50 ft from the house. Is the garage 3' below the ground of the crawl space or 3' below the floor of the house? Do you know where you sewer pipe is under the crawl space?

I take it that the new drain line will be three inch. In 50' at 1/4" to the foot fall that will give you a drop of 12 1/2" from the garage to the house. Never mind the house connections. How deep is your sewer line? And yes, the both the sink and the washer station will have to be vented, no second vent will be needed. Good luck, Tom

Have you considered draining this water to the garden and using it for irrigation purposes ? Or digging Dry Well and draining it into it ?