Infiltration of rainwater, which method?

Hi,

we will start building soon and the building permit-free procedure was also not opposed.

However, on the advice of the general contractor, we informed the municipality that the rainwater will infiltrate through a basin in the garden.

The authority specifies:
The rainwater shall/must infiltrate, a calculation of the infiltration system according to ATV-DVWK A-138 is required and must be verified. An infiltration test or an equivalent laboratory test is required.

We ourselves have no idea about this topic. I have already tried to read up a bit, but the whole subject seems very complex.

So, as I said, we indicated a basin, so the municipality could approve it itself and did not have to refer it to the lower water authority.

One neighbor in our new development area installed a Sickeriglu and finds it much better than a basin, as you don’t have a "wet biotope" in the garden with it.

The second neighbor who has already built (he had his property filled up with the same earthworker/landscaper as we are using) had an infiltration system (Rigole) installed.

Now I’m wondering what is better/cheaper?
Attached is the offer, which also includes the infiltration system (Rigole).

The Sickeriglu seems to be quite a bit cheaper??

I hope you can help me so that I know the best way to manage the infiltration.

Hello,
first of all, Rigole, please

Sickeriglus need more space than Rigolen in box form.

I don't know what a Sickeriglu is but we have placed a septic shaft. These are just a few concrete rings and one on top with a funnel-shaped form on it. The bottom was filled with coarse stone material. I can't tell you the cost because we had an all-inclusive offer from our earthworks contractor. You can just drive to the hardware store and then you'll already know the price of the part. You just have to discuss the labor with your earthworker.

A prerequisite for rainwater infiltration is an infiltratable soil. This must have been specified as a permeability coefficient (Kf value) in the soil report, which should be available to the planning engineer. If the infiltration capacity is not given, planning a soakaway trench is unnecessary. If applicable, a seepage shaft (concrete rings, etc.) can be planned, which reaches infiltratable soil at greater depths. Provided that a minimum distance of 1.00 m from the highest ever measured groundwater level is maintained. This applies to both the soakaway trench and the seepage shaft.

If none of this can be demonstrated by a planning office, a special permit from the municipality should allow the discharge of rainwater into the sewer system. The most cost-effective solution.

So the soil we received should definitely be permeable. There is no clay mixed in either.

Which items explicitly refer to the [Rigole] (apart from the one labeled as "Rigole" of course)? But I do find €3,300 net quite a lot for a [Rigole].