Is drainage required behind non-retaining concrete boundary walls?

[Akel]

So I know that if I have a retaining wall, I have to provide proper drainage using weep holes or perforated pipes at the side with the higher fill to reduce the hydrostatic pressure acting against the wall.
But what if the grading is equal on both sides of the wall and there is no hydrostatic pressure buildup. Does drainage need to be taken into consideration or can I just let the water accumulate and soak away into the ground without much to worry about?

I'm working on a pump station where a water tank is situated at a high point in the middle of the site and the ground then slopes down all around it until it reaches the concrete boundary wall. The site is so packed with underground utilities that I can barely fit any catch basins or trench drains if required.

 

[cvg]

assuming the tank leaks, you could have saturated conditions on the tank side of the wall. probably should provide drainage through the wall for that as well as for stormwater runoff.

 

[Akel]

So drainage should be provided through the wall using ground level weepholes or through wall scuppers?
And how would the sizing and spacing be determined. Do I use the standard sizing and spacing as if the wall was a retaining wall or would I treat the wall opening similar to roof opening and size them using plumbing codes?

 

[cvg]

I think scuppers is probably a better option. size the openings large enough so the hydrostatic load on the wall is acceptable.

 

[Akel]

Thank you.