Hi - I originally posted my question in the plumbing section, but now that it involves the use of a pump, I thought I'd ask it here. To summarize - I need to reroute "gray water" sewage (Kitchen sink/dishwasher and laundry) around my house and tie into existing sewer line. I'm unable to get enough gravity flow given the fact I have to go 120 ft and given how deep the sewer line is that I need to tie into.

The sewer pump I've found (Zoeller) can be bought preassembled in a 30" deep basin meant for underground burial. a 4" inlet and 2" outlet. Again, this is kitchen sink/dishwasher and laundry water only. Pipe those two things into it and run pipe out of the discharge around and tie in to the sewer. Cap off the old drains. Cut vent pipe in the wall, cap it off, and tie new lines back into it (it goes out the roof). My question: Will deep freezes make this system inoperable or will each cycle of the pump empty the basin??? The pump I found will pump water 18 feet straight up. It does not specify how far horizontally it will go. I will try and keep the pipe as level as possibe. Should I run 2" pipe all the way around to increase the pressure in the pipe? I'm not sure if this pump with each cycle will be able to completely flush out the line or not. What do you guys think?