Lowering of groundwater according to soil report - Your experiences?

*EDIT* Of course, you should always have a plan B in reserve in case you have grossly miscalculated or if the groundwater level should have risen extremely due to a record rainy summer. For our case, this specifically means that we keep another set of plans ready for approval, in which we lift the house about 32 cm above the ground. This would then disrupt accessibility and the planning of outdoor facilities, but there is nothing worse on the construction site than nasty surprises that become really expensive and cause delays because you were not prepared for them.

Old Finn. I would install a water flow meter for €500!!!
I can’t imagine this amount.

There is always theory and practice!

Old Finn. I would install a water flow meter for 500€!!! I can't imagine this amount. There is always theory and practice!

The neighbor pumped 44.45m³/h of water per hour in 2013. My calculation came to 44.58m³/h. And yes, I couldn't imagine it either, but the nice man from the city gave me many reference construction sites that I also visited. When you then see what volumes are flowing there, you are speechless at first. We even planned 2 dry-running water meters DN100 after the sand trap to be able to measure the volumes at all. These are water meters with diameters you can stick your arm into. We had to get used to these dimensions for a long time. The volumes are not that big. There are construction sites with millions of cubic meters of water; what we do compared to that is just paddling in puddles :-D

the thing with the neighbor as a reference is of course something different. I was not aware of that.

I just can't imagine that 40m3/h run through the drains, that's over 10l/second.
But definitely keep us updated

We thought the same at first, that the drainage pipes couldn't handle it. In total, about 60m of drainage pipes are laid in a special pattern, and the two infiltration wells with a diameter of 400mm are also coarse-pored perforated. The slope of the drainage is also significantly greater than in "normal" drainage systems to direct the water faster to the outfalls. Finding this out was part of the hydraulic calculation. There is also the option to lay the drainage pipes on top of each other, but that would only have a positive effect at the beginning of the pumping work. Once the drawdown cone has settled and the water column decreases in the surrounding area, the water pressure and the associated inflow also decrease.

Approximately 22,000 m3 were pumped out in the 3 weeks with us. Your 29,000 m3 can therefore be realistic.