Using rainwater for the house?!

Hello

Does anyone have new information about the costs of the [Regenwasseranlage]?

Best regards

The cost of such a system depends on many factors.

How large should it be

What material

Should the water be used only in the garden or also in the house

If also in the house, e.g. for the WC, then an extra pipe must be installed

Furthermore, an additional water meter is required.

Can the system be built by oneself or must a company take over.

This means something like this might cost around a thousand euros, but as is often the case, there is actually no upper limit.

I myself built something like this a few years ago on my own to save on the rainwater fee. The water is only used for the garden and thus it takes me about 5 years for the system to pay off.

Thank you for the response, my primary concern is to use the rainwater sensibly. Definitely for the garden, since the house is not built yet, the consideration to also use the rainwater in the house. At the moment, I find it somewhat difficult to calculate the costs to determine whether it is worth it or not. Regards

To my knowledge, using rainwater in the house is rather not worthwhile or only with a very very long payback period. More expensive than the drinking water costs are the wastewater costs, and you have to pay those anyway.

At the beginning of the year, I was considering whether to get 2-3 IBC containers for garden irrigation. I then calculated what 3 containers with a pump and connection sets with some cladding would cost me. I came to about €400 without cladding and €600 with some wood around if it should look a bit nice. If I could save maybe 2/3 of my last year’s consumption of 30m³, that would be a lot. I watered the lawn almost every day since it was extremely dry and hot here last year for a long time. You can even sometimes get exempted from wastewater charges for the outdoor water tap. Unfortunately, with us, only from 93m³ with 3 people. I needed that much including irrigation, so I can only offset the saved drinking water costs of about €2.50/m³ and would come to €50 with 20m³ per year. So at least 12 years payback time. For that, you need the space for the 3 containers. For me, the tap is simply more comfortable. Turn it on and that’s it. Also, the water pressure here in summer is so high that I can reach exactly from one side to the other with our sprinkler. I probably would not manage that with a pump and would have to move the sprinkler several times.

I find the fancy rain barrels for €200 and more for 300l interesting. You probably need more than 40 years until they pay off. Whether they will even still exist then is doubtful.

I built something like this myself a few years ago to save the rainwater fee.

Wastewater costs are more expensive than drinking water costs, and you still have to pay them.

I don’t know to what extent this varies from state to state.
Our 10 m³ cistern has an overflow into the sewer system (as can be seen this year, this is useful). Due to the overflow function/the connection to the sewer, we continue to pay wastewater fees for the rainwater.
Unfortunately.

The wastewater fee for drinking water consumption is based on water consumption.
Thus, we save the purchase price per m³ of drinking water for garden irrigation and (since we do not use the drinking water for irrigation) also the wastewater fee for the drinking water not consumed.

For me, the tap faucet is simply more comfortable. Turn it on and that’s it. Also, the water pressure here in summer is so high that with our sprinkler I can reach exactly from one side to the other. I probably wouldn’t manage that with a pump and would have to move the sprinkler several times.

Our pump has a pressure of 5 bar. Thus, the pressure arriving at the irrigation nozzle (we do not yet have a sprinkler active) is significantly higher than at the tap faucet.

I don't know to what extent this varies from BL to BL. Our 10 m³ cistern has an overflow into the sewer system (as can be seen this year, this is sensible). Due to the overflow function/the connection to the sewer, we still have to pay sewage fees for the rainwater. Unfortunately.

The sewage fee for drinking water consumption is measured based on the water consumption. So we save the purchase price per m³ of drinking water for garden irrigation and (since we do not use drinking water for irrigation) also the sewage fee for the drinking water not consumed.

My first paragraph was referring to the previous post, which was about the use of rainwater as utility water, e.g. toilet flushing. Of course, sewage fees have to be paid for the rainwater used there.

But you are right, in my calculation I only indicated the drinking water. If one cannot be exempted from sewage fees, then of course both drinking water and sewage fees would have to be considered for the 20 m³. I am curious to see how much we will use at the outdoor water tap this year. I think by far less, so that the 20 m³ saving would already be a very high estimate. I will recalculate this in autumn after the 2nd season.

Our pump has a pressure of 5 bar. This means that the incoming pressure at the irrigation nozzle (we don't yet have a sprinkler active) is significantly higher than at the tap.

That is interesting. What kind of pump is it? I have our water pressure also set to over 4 bar.