We have a beautiful new house. We fenced in what little of the backyard there is. Our 2 large dogs only go back there to do their "business" but between running around back there and their "business" they have ruined the lawn! The area is shaded by the house and overhanging trees and sits atop a rather steep slope (slopes into Federal wetlands). Now the area is a combination of nasty mud and weeds. Not to mention it stinks! We try to pick up the poo as often as we can but it doesn't seem to help the odor. I need some inexpensive suggestion of how to fix the mud/erosion/weeds/smell! HELP!!!!!!

Big dogs need big space. Especially if they are active breeds which like to run. You have to have enough space for them or exercise them morning and night. Small space = smaller dog.
Maybe you can concrete/pave and otherwise hardscape the area so it's indestructible but there isn't a quick fix i'm afraid. Unless you get rid of the dogs..

With the location and already present drainage problems, hardscaping probably isn't an option. There has to be something resilient that we can plant back there that can take mostly shade, foot traffic, and dog urine.

is there any way you could train the dogs to only go in a certain area?? it would be easier to clean just that one spot and you'd be able to replant in the other areas.

Unfortunately that is beginning to seem like my only option. My dogs are rather unruly and spoiled, I am ashamed to say. The whole idea for the fenced in area was privacy and a place for the dogs. Neither of my goals was accomoplished. Not only can my neighbors look over the fence but the dogs have torn the area up (and are tracking huge amounts of mud into the house). It has been a disaster all the way around.