Pumping groundwater - costs?

Hello everyone,


I finally registered here today because I have a question that neither the local search nor Google and other internet research could answer for me (or I was simply too stupid to find something ).
So I am really hoping for your competent help
Here is my question/problem:

My construction project in Bavaria (approx. 9x10 m external dimensions) includes a basement. I estimate that the groundwater starts at 2-2.5m and suspect that digging will have to go to just under 3m. Of course, it will be built with a white tank, also with watertight windows, B2 construction site, etc. All of this is settled and I hope that’s fine.

The big question I have, however, is... what costs should I roughly expect to lower the groundwater accordingly during the construction period??
Pump rental, sewage fee (possibly I’m allowed to discharge into the nearby river – but then I would need a "sand filter", right?), what rental or operation period should I expect, etc.?

As I said... previous research has not really helped me much... I either only find general groundwater information or total costs for a basement and similar... but I simply cannot find the specific costs expected for pumping off the groundwater. I would be grateful just to get a rough estimate so I can somewhat include it in my overall cost calculation!

I would be very grateful for your help!!


Regards,

Bully

....The big question that arises for me, however, is.... what costs can I approximately expect to lower the groundwater during the construction period??
Pump rental, wastewater fees (possibly I’m allowed to discharge into the nearby river – but then I need "sand filters," right?), what running or rental duration should I expect, etc.?

Counter question: How much water is there or needs to be held? For how long? What is the pressure loss (energy expenditure) for the transport? Which pump (capacity) is needed accordingly?

Best regards

Ok.. those are very smart counter-questions... if only I knew all that! ^^ I am working with a full-service provider (yeah yeah... I’m already gaining experience, but the contract has long been signed ), partly because I have (still) no clue about the details :/ Unfortunately (one of the experiences) they are very reserved about any statements regarding "variable costs" and are not really helpful with such questions.

The small river I might be allowed to divert into is only about 20 meters away (more or less on the other side of the street) and the entire site is quite flat – so no slope or anything in any direction. How long does it have to be held? Well, I guess at least until the basement is built, or how is it usually?? Since I don’t have a soil survey and the pit has not yet been excavated, I also don’t know which pump/performance is necessary... sorry if it stays so vague... but I would be grateful if I could get some orientation (ideal case/average/worst case)... at the moment I’m completely standing here without anything... whether it will be 200 euros or more like 20,000 euros?? I’m broke, hence my noob question here in the forum

Of course I included a cost item "ancillary construction costs" in my calculation, under which this also falls... but whether that will be blown up due to groundwater, or if I might even save something... that’s what I’m trying to find out!

Thanks anyway for your response!

If you don’t have a soil report, you can forget about planning anything.... don’t underestimate the earthworks. We are building without a basement and still have a total cost of 20,000 on a “fairly level” plot. In any case, plan for the worst case... that is the basement with a white tank around 50,000 € and then something between 2,000 and 10,000 for the pump. Then there are the earthworks, connection costs, etc. etc.... so it might be worth reconsidering whether to forgo the basement.

Before signing, definitely have a soil report and surveyor come. Otherwise, you can forget about estimating the costs beforehand.

Hello,

My construction project in Bavaria (approx. 9x10 m external dimensions) included a basement....All that is clarified and I hope it fits like that.

I hope so for you too, because building without a soil survey – even with apparently good soil conditions – is already quite reckless; with groundwater actually just below the turf layer, it is basically inexcusable!

The big question that arises for me, however.... roughly what costs should I expect ...

Neither €uro nor any other user can reliably and seriously answer that, as the figures vary from federal state to federal state and then again for each city/municipality; moreover, the specific peculiarities of the construction project must be considered. In any case, there is a municipal fee involved, because you need a water law permit.

Kind regards

@ The Da: Thanks for your feedback; it is already signed, the basement is definitely included. In the immediate neighborhood there are already (older) houses with basements... so I started off inexperienced without a soil survey.

@ Building expert: Fine, now I know from you that I am building recklessly and no one will be able to tell me otherwise. Thanks as well, very helpful.

To everyone else who still wants to make a statement, I would still be grateful - as I said, I do not expect definite statements (that every situation is individual is clear to me ), I am grateful for orientation and possibly experience from builders in similar situations.