I have searched and read all threads related to what I need to know, so at least I have a better understanding what to do.

First off, am a renter and do my own maintenance for lower rent. Old house, maybe 75 years old or so. 3 bedroom, one full bath, kitchen sink (no disposal) and washer drain. All plumbing is on main floor of house.

Toilet goes to septic via cast iron (6 or 8") had it drained a year ago no problems there at all.

Slow or stopped up gray water drainage has ALWAYS been an issue. Gray water line goes out basement through dirt area in floor, under basement slab and down a large hill, roughly 150', sadly I just found out . . into a river. Needless to say it needs to be diverted and decided now was the time.

Tried digging behind the house to find the gray water line and could not find it. Either too deep or it does some weird bends I am not aware of. Had planned on digging a dry well system to eliminate the water going to river. Obviously cannot do this if I cannot find the pipe.

Plan B is to divert bathtub and bathroom sink on one side of house and kitchen sink and cothes washer drainage (by sump pump) on other side of house into the cast iron pipe going to septic via a "y" pvc joint into a saddle I believe it is called.

Was going to put a screen of some sort over the washer outlet to capture stuff that could clog the septic ports. We already use organic dishwashing liquid and clothes detergent, am working on getting roommate to switch to some sort of organic shampoo/soap as well.

We don't use a vast amount of water, maybe 2 days a week for laundry, showers most days and dishwashing etc. From what I have read, it seems within code to divert all this gray water to the septic. I believe that question has been answered for me, correct me if I am wrong.

Again from what I have read, it seems BETTER to divert washing machine water elsewhere as it can overload the septic system. Problem is I have neighbors close on both sides of the house, septic area out front and steep hill in the back down to the river.

Where and how might I divert this wash water via pump without digging a three foot deep trench underneath my basement slab out the back of the house? Any other lines I simply run outside would surely have a freezing issue in the winter (live in Central New York State).

There IS what looks to be an old galvanized line going out the front foundation of the house that I am ASSUMING used to be for gray water. I am skeptical of tying into this line to pump wash water out, as it is near the septic/leach field and to be honest I don't know how far from the house it goes.. . Or if it goes anywhere for that matter. Do not want to pump wash water around the foundation of the house.

Any help comments or suggestions would be greatly appreciated. Hope I did not go overboard just wanted to give the best picture of what we are dealing with here. Many thanks in advance.