What is the cost to fix concrete wall leak?

I have a separate entrance for my basement in the backyard and the concrete retaining wall has holes from which water continuously leaks. This is at the bottom of the stairs in front of the back entrance. That area is always wet and overtime this has created the area displayed in the picture.

I received responses on possible issues:

- Drainage needs some attention at footing levels and possibly at grade level as well.

- I would recommend that the retaining wall be water proofed with blueskin membrane on the opposing side of retaining wall, and this membrane should extend down to footing and draintile. Assuming that draintile is in decent shape this should fix your problem.

- With out moving some dirt there is not a whole lot that can be done with this issue.

- You have a poor drainage on the other side of the wall.

What will it cost to get this fixed?

Please let me know if you need more pictures or videos.