Looks more like a crushed pipe to me. Backfill PVC pipe with sand, not what you dug up. As @Artisi says, make sure that pipe repair is supported. If that were me I'd dig out, chop each side of the 90s and turn it on its side. Like it is I think you're creating another future problem. IMHO.

8 minutes ago, Artisi said:

does the Mitsubishi pump feed the inlet side of your pool pump?

 

The pipe goes from the Mitsubishi outlet over about 70 meters of length to feed water taps in the garden.

 

Half way is a T-junction where this pipe goes to a shower mounted at the pool pump house.

 

The same 70 meter feed also provides top up of the pool and is connected to the skimmer pipe inside the pump house.

 

The Skimmer pipe is of course directly connected to the suction side of the pool pump, so if the pool pump is running at the same time I top up, it probably sucks the water out of the feeding pipe.

 

I'm not sure if the top up pipe is an extension of the pipe that feeds the shower, or a different connection further down. I suspect the latter.

 

The Mitsubishi pump also provides the kitchen and the maids quarters, and i know for a fact that when I'm topping up the pool and the pool pump is running, I don't have any water in the kitchen

No, check valve just stops backflow of water from the discharge pipework.

 

Also the foot valve section that fell off needs to be hooked out of the tank before it blocks the pump suction.

6 hours ago, grollies said:

Backfill PVC pipe with sand, not what you dug up.

Why should I not use the sand I have dug up?

 

To fill the hole I use lot of water to make it flow into the smallest gaps, and have added builders sand as well to it.