"i want to add a bath to detached garage. the floor is ground level. i want to tie in to drain line at my house which is aprox. 40 ft. in front of my garage. the house has crawl space making the drain line elevated at the back and slopes toward the front of the lot. how can i get any fall at all on the drain line to the back of the house. can drain water including toilet be pumped someway?" . . . .