Collect rainwater or drill a well?

Good day!

The ongoing drought is once again bringing up a topic for me that I have postponed several times: Where to get the water for garden irrigation? So far, it comes from the public network: always available, always enough pressure, and thanks to separate metering, also reasonably inexpensive. But actually, it can't be sensible to let high-quality drinking water seep away in the garden.

Is there a rule of thumb as to which form of garden irrigation is best from a financial and ecological perspective? Basically, there are three options to choose from: water from the public network, collecting rainwater from roof surfaces in cisterns, or drilling a well (if permitted).

For the use of rainwater to pay off, you would have to be able to store a lot of it, at least 20 to 30 cubic meters, to be able to bridge dry periods. Accordingly, the costs for cisterns and the associated earthworks would be high. And then the ongoing costs such as electricity and maintenance for the pump. Drilling a well also, of course, causes costs, plus electricity and maintenance for the pump. The advantage of the well: you don’t have to worry about storage capacity.

My garden irrigation (drip hoses under the mulch) consists of four circuits, each of which requires one cubic meter per hour. In case of persistent dryness, I would like to run each circuit for an hour every two to three days. That would be about ten cubic meters per week. With 30 cubic meters, you would therefore only get about three weeks. And in Berlin, we more and more often have situations where it doesn’t rain for significantly longer than three weeks.

Has anyone of you ever gone through this in detail?

Matthias

If the opportunity for a well arises (and you do not have to drill 30m directly, or only have 100sqm to irrigate), the well always wins. If necessary, it can even be created in EL.

If the opportunity for a well arises (and you don’t have to drill 30m right away, or only have 100sqm to irrigate), the well always wins.

If there is water. Have you ever checked at what depth water would be? If yes, how much? Not every well is as productive as you might wish. If there is water, I would also drill the well. BUT: well water is almost always very hard. Not all plants tolerate this hardness. A gardener would probably always advise you to use the cisterns. We have both and I am very glad about it. All undemanding plants like hedges and trees get the well water. The mimosas get rainwater.

Not all plants tolerate this hardness. A gardener would probably always advise you to use cisterns.

Really? Who doesn't like the water. I always like to learn. Maybe in the past I have always unconsciously avoided the mimosa among the plants.

I assume that after just a few meters we have a lot of groundwater here, but that can be checked when it gets more concrete. Maybe it will be a mixed solution, meaning that at least a little rainwater is collected, more than before, to water the few plants that need little lime, especially rhododendrons. It's really fascinating: if you water them with tap water, they do not form buds. If you consistently water them with rainwater, there is a rich display of flowers.

Well, then just put a rain barrel there from which you then take water for certain plants. And for the rest, the well.