ᐅ Rainwater Harvesting Tank: Yes or No, and Which Material?

Created on: 18 Jun 2015 15:36
K
kernm23
K
kernm23
18 Jun 2015 15:36
We are currently planning a single-family house.
I am undecided about a concrete cistern (concrete for durability).
The plot is about 800 m² (8600 sq ft). The cistern is intended for garden irrigation (although not much will be cultivated in the garden). How large should the cistern be at a minimum?
What costs should I expect?
Is the investment worthwhile?
How is the water withdrawn? Can the cistern be connected to the outdoor tap?
N
nordanney
18 Jun 2015 15:45
Do you need to build a cistern? Could a well be a (more affordable) alternative (depending on the groundwater level) – here in NRW, many cisterns have run completely dry in recent weeks, so the garden had to be watered with expensive tap water.
K
kernm23
18 Jun 2015 15:49
No, we don’t have to build a cistern! How can I find out if a well is permitted? What costs should I expect?
T
tbb76
18 Jun 2015 16:02
It’s best to check with your local municipality about having a well. They are not permitted everywhere, as there must be sufficient groundwater available. If you are building on a hillside with a nice view, the chances are low; if you are in a valley near a flowing water source, the chances are better. But as I said, inquire with your municipality about any regulations or maximum extraction limits. Depending on jurisdiction, they might also refer you to your county or district office.

However, if you are using a rainwater cistern for garden irrigation and need to have a hole dug anyway, it’s better to go for a slightly larger size, especially with cisterns made from concrete rings.
f-pNo18 Jun 2015 16:10
You wrote that a cistern is not mandatory. Are you referring ONLY to the cistern?
For example, where we are, a suitable rainwater infiltration system is required. This can be an infiltration pit, soakaway, pond, or a cistern.

You might want to check again whether something like this is necessary. Either way, this will incur costs for you – so in my opinion, choosing a cistern makes sense because you can use the rainwater and avoid paying for both tap water and wastewater.

Edit: By the way, there are already threads on this topic here in the forum where you can find more detailed information.
Musketier18 Jun 2015 16:17
Does a cistern ever make sense if it is not required?

From a certain level of water consumption, it is possible here to be exempted from sewage charges for external water use. Then, the cost per cubic meter is only 2.xx€ instead of 6-7€. The neighbors used about 20-30 m³ (700-1,060 cubic feet) last year.
Now you can compare the purchase costs plus interest expenses against that.