Rainwater must be obligatorily infiltrated

Hopefully no more fees will be charged for infiltration on your own property :)

You still have a lot to learn. Our municipality uses soakaways with a factor of 0.1 for rainwater.

Much learning you still have to do. Our community uses soakaways with a factor of 0.1 for rainwater

Oh, ok. The logic on the part of the community doesn’t really make sense to me, but in the wild south, everything seems possible... ;)

Either you have a building plot that is relatively even. Then it doesn’t matter if you move the house by 3 meters or make it 1 meter wider. Then you can also do the soil survey early. Or you have a building plot that is completely different every meter. Then, despite drilling at the corners, you still get surprises when the pit is excavated

Yes exactly, and that’s where the problem lies :-). I’ll take care of the soil surveyor, I’m pretty sure the house will stay where it is currently planned.

Depending on the municipality, you can simply put a water meter on the outdoor faucet (for garden use) or register it and in the end you don’t pay sewage fees for the amount of water used. Some have it sealed by the water supplier, in others you can simply “register” your own meter and that’s it. These cost little money and pay off quite quickly because the costs without the sewage portion are considerably lower for the consumption.

That’s very interesting, I’ll ask about that! Theoretically, it should be much easier to arrange. Why do I have to pay sewage for rainwater at all when I don’t have any connection to the sewer for it? That somehow doesn’t make sense, right?

That’s why I mentioned before on my side that in the end no one cares about the execution. It’s only an inspection and approval on a documentation basis. You yourself are obliged and responsible regarding the execution.

When I spoke with the guy from the building authority, he said there would be a corresponding acceptance at the end of the construction project. No idea if there is any truth to that…

We had no inspection at all, but also no requirements regarding drainage. It was said that infiltration must take place. How it should look, nobody prescribed and nobody cared. We just perforated a few big barrels and buried them. Gravel and fleece around, some gravel inside, lid on, done. It worked for 15 years at the old house with a similar roof area, and it will work again now. With very heavy rain it sometimes overflows, then it simply infiltrates into the garden. But we also have Märkischer sand, so it disappears quickly.

We also had/have no direct requirements, there was only the letter from the authority in which what I wrote in my initial post was stated. Only on the phone did the gentleman say we couldn’t avoid a cistern. After a phone call with the house builder today, he said it would be strange to say such a thing on the phone, because if there was an obligation for a cistern, it would have to be mentioned in writing, which is not the case for us. From that I conclude that we probably don’t need a cistern, it was just a wish of the building authority person.

You still have much to learn. Our municipality uses soakaways with a factor of 0.1 for rainwater

That’s exactly the kind of nonsense I expect…

I have now also done a bit of research online, I am roughly assuming a concrete cistern price of about 2k (>6m3 with pump and co). Can someone also roughly say what the rest could cost, like excavation, embedding, and co?

And a completely unrelated question. I would rather not have a thing in the ground with a hose sticking out, is there not also a way to connect it to a water tap that is on the house wall? Could not find such a solution online.

Why do I have to pay wastewater charges for rainfall at all if I have no connection to the sewer for it? It kind of doesn’t make sense, does it?

You’re mixing something up there. Normally, of course, you don’t have to pay for the water in the cistern. It was only about the cost-benefit discussion or comparison between fresh water, well, and cistern earlier, e.g. for garden irrigation. I just added that a cistern purely for that purpose is not economically worthwhile... With high consumption and after many years compared to fresh water use, maybe, but the latter is also cheaper, if you can save the share for wastewater (-> meter).

When I spoke with the man from the building authority, he said there would be a corresponding inspection at the end of the construction project. No idea if there’s any truth to that...

Of course, there is an inspection for the construction. Normally. At least in our area, the drainage solution (infiltration basin...) is not inspected. Nobody cares about that.

We also had/have no direct requirements, only the letter from the authority that said what was in my original post. Only on the phone did the gentleman say we wouldn’t get around a cistern.

If one is not required in the development plan, then you probably can get around it. Maybe the good man on the phone mixed something up (cistern, infiltration basin ...) or just expressed his personal opinion for other reasons.

I have now also done a bit of research online, I’m assuming a rough concrete cistern price of about 2k ( >6m3 with pump and co). Can someone roughly say what the rest might cost, like excavation, burying and co?

To the very rough 2k, add transport costs and handling with the crane on your property. You can roughly calculate excavation and disposal costs, let’s say 30-40 EUR / cubic meter.... Plus installation .... possibly with foundation depending on the design .... In the end you might be at 3+ k€.

And a quite unrelated question. I would rather not have a thing in the ground from which a hose sticks out, isn’t there also a possibility to connect it to a water tap mounted on the house wall? Couldn’t find such a solution online.

Hose sticking out of the ground? What don’t you like about, for example, a "water tap column"? Otherwise, of course you can pull the hoses however you like and connect them to a wall tap.