A wildlife portal and a cat stuck in a pipe{I need advice, please!}

The wildlife portal seems to be an old swing set.  Tristan had lots of fun on that old set as he was growing up and once he was too old for it, we re-purposed it as a bird feeding station.  I had also placed hanging plants up there for a while but the birds droppings killed the plants. So now, just feeders. 

That is about to end.

We put up several feeders and unfortunately attracted the squirrels, thus wiping out the seed within hours.  What I came to learn was it's not only birds and squirrels who like to eat black sunflower seeds.  Foxes, rabbits and raccoons also raided us.

Here is the fox - busted - coming right up to the house and stealing seed. 



Several other times we saw rabbits sitting on the stumps, munching away.  I didn't know they ate sunflower seeds!  One evening this past week we were eating dinner on the patio, it got dark and the colored lights were flicked on.  Out in the yard we heard movement and it turned out to be two fat raccoons.  One climbed up onto the swing set and robbed seed and the other gorged off the laden tree stumps.  This is while we are sitting about 18 feet away with only a fence between us and them.

They are getting too bold and with a recent story in the news about a fox jumping a fence and attacked a child, we know this has to end.  The plan is to take the swing set apart and remove it altogether.  These are wild creatures and they need to hunt and get their own food.

Now - the cat in the drainage pipe is another matter completely.  We don't know what to do. A few months back it was very cold, probably 26 degrees overnight.  We get up and hear this meow out on the porch, go out to investigate and don't find a cat.  But it starts up again and we realize it's most likely made it's way up inside a drainage pipe and we are hearing it through the French drain on our back patio.

Since we'd had issues with water collecting in the yard a few drains were put in and a PVC pipe buried, draining the water into a fire break about 40 or more feet from our patio.  Evidently this cat (we'd noticed him out in the field one day, big fat stray I'm guessing) crawled up inside to get warm.  Or maybe to chase a mouse, then couldn't figure out how to back out.  No way is there room to turn around so it would have needed to back out.

Fast forward a bit and the weather is getting a bit warmer.  Now we are getting this horrific smell coming from the drain area.  That cat probably suffocated and the smell is just about unbearable.  It's not constant but when a shift of wind occurs that smell hits you and will run you inside.

We've tried filling large trashcans with water and dumping it through.  We tried bleach and more water, in great volume. It seems to make it better initially and then the smell comes back.

When Doug first started dumping the water into the drain nothing came out of the pipe in the fire break.  Then three barrels later it started trickling.  Then a mouse came running out as the water started flowing.  We saw hair, definitely the color of that orangey cat so we thought - progress, it should wash out soon.  So far we haven't seen any bones or anymore hair/fur.  And then the smell comes back again.

Any advice?  Besides digging up our field and the pipe I don't know what else to do. Since it's underground this cat won't have the sun breaking it down or vultures coming after it.  Who knows how long it will take to break down.  So seriously....any advice?  Anyone else have this sort problem..... ever? 

I'm open to ideas as wasting gallon upon gallon of water doesn't seem to help. Yet.

Whew.