ᐅ Building on soakaway pits—how to proceed?

Hello everyone,

Two separate soakaway pits are planned for rainwater drainage—one collecting water from the roof and the other from the roof terrace. Both soakaway pits are constructed similarly: digging a hole, filling it with gravel/aggregate, connecting the downpipe, placing a geotextile membrane on top, and then covering it with soil.

Both pits are underground and not visible. Is it safe to build over them, for example with a terrace or something similar? While this is probably possible, what happens if you need to access the pit later due to blockage or other issues?

Does anyone have better suggestions?

Thanks

Wouldn't that cause overbuilding? Leaves, bird feathers, and other debris accumulate there. What do you do if the water no longer soaks away because a clog of dirt has formed at the pipe outlet?

Can’t you design the pits in locations where they won’t get in the way and, if necessary, remain accessible?

Usually, gravel is used for such pits.
It cannot be properly compacted and therefore, in my opinion, is not suitable for building on.
I’m not sure if such a pit can also be made with compacted crushed stone; it’s probably possible, but the dimensions would need to be larger.

Do not build over it, as this will only cause problems if access is needed later.

How about infiltration trenches or infiltration tunnels? They can be built over and driven on. The entire infiltration system also includes an inspection chamber with a pre-filter.

We also installed infiltration trenches at our place, but they are located under the lawn in the garden.