Recommendations for a garden pump to empty a shaft

My wife loves the rainwater from the [Zisterne] for her plants

I have the "Hauswasserwerk" from a cheap provider for 99 euros standing on the cistern. It has been working for 8 years!!! (You could also buy a new one). Sure, there is "noise" outside. But for the true gardener, the sound of the pump is music for 1 - 2 hours!!!

The water is quite clear and probably comes from some kind of underground spring. It also made the earthworks quite expensive. The earthworks contractor diverted the water into the newly constructed shaft and regularly pumped it out during the work. The shaft has been full since yesterday, and the water is now pushing up elsewhere. We want to use the water both for watering the garden and the indoor plants.

What happens if you don't pump it out? Does it overflow or do you have a spillover?

There is an overflow present. As a layperson, I have the feeling that water at a height in the shaft of about 10 cm below the overflow no longer has the force to push itself into the shaft, so that it emerges at a low point next to the shaft.

Wow, maybe you have a picture of it? I can't really imagine it right now. So if you want to take it from [zjk Gießen] etc. like from a water tap when needed, then a domestic water system. They are very cheap online.