Collect Rainwater

2023 Author: Hannah Pearcy | [email protected]. Last modified: 2023-08-25 03:36

Rainwater is not suitable as drinking water, but that does not mean that it does not have any authorization in the garden and household. After all, the use of precious drinking water for flushing the toilet, washing the laundry or watering the flowers is actually much too good. But how can you collect rainwater ? And is a rain barrel enough or is it even worth the effort and cost for a water tank? We'll tell you!

Garden maintenance

rain barrel for rainwater use

In a rain barrel, free rainwater can easily be pre-treated

Collect rainwater: Safe and harmless

Concerns about the quality of the rainwater are mostly unfounded. After all, the water should not be used for drinking and cooking. A large part ends up in the toilet, which is why the use is completely harmless. When washing clothes, however, it should be borne in mind that the water is initially heated to such an extent that all germs are killed, but this cannot be guaranteed in the subsequent rinsing with cold water. Subsequent ironing can then render all germs harmless.

However, the Federal Environment Agency points out that there is still a residual risk for people with a weakened immune system - such as the elderly, children and the sick.

Collect rainwater for the home and garden

We use about 120 liters of water a day. We only drink the smallest part of it. The three biggest water eaters in the household are:

1. Toilet flush: 40 liters
2. Showering or bathing: 20 to 40 liters
3. Wash laundry: 19 liters

What sounds a lot is actually comparatively little. Modern technology alone means that we use over 50 liters less water every day than we did 20 to 30 years ago - without our intervention. Of course, there are still suggestions for improvement: showering instead of bathing, replacing outdated devices etc. But why not simply collect and use rainwater ? After all, this is not only useful for watering flowers. By using it for toilet and laundry, about 60 liters per person and per day can be saved, i.e. a good 50 percent of the water requirement.

Rain barrel or rainwater barrel

Probably the simplest and cheapest way to collect rainwater is in a rain barrel or a rain barrel. Thanks to special rain collectors for the gutter, rainwater can be collected quickly and effectively, and with the connection of a garden pump, it can even be used to blow up the lawn. A rain barrel not only saves money, but also watering the flora in your garden by watering with lime-poor water.

Rainwater tank: Collect rainwater for the household

A simple rain barrel is of course not sufficient for the needs of an entire household. A cistern has to be built and it has to be embedded in the floor or stowed in the basement, equipped with a filter system and connected to the household water supply. Before purchasing, you should therefore first make sure that your roof is even suitable for the treatment of drinking water. The roof covering must be made of clay, slate or concrete. In addition, a partial exemption for the drinking water supply must be requested from the drinking water supplier and the system must be reported to the health department, but not approved by it. Before starting construction, you should always ask your municipality whether financial subsidies are possible for your system.

Collecting rainwater with a cistern: is it financially worthwhile?

To purchase a complete system, you have to plan between 2,500 and 7,000 euros depending on the size of the system, its location and whether it is a new building or a subsequent installation. There are also annual maintenance costs of around 100 euros.

You can collect a lot of rainwater with a cistern.

According to the Federal Environment Agency, the savings for a four-person household are around 160 to 200 euros per year. If this is counted against the purchase and maintenance costs, it can take up to ten years before the purchase pays off and even then the savings amount to a maximum of 100 euros per year. However, numerous other factors such as annual precipitation values and roof pitch also play a role here. The size of your garden is also crucial, as the rainwater collected can also save money on irrigation water. How sensible a purchase is should therefore always be decided individually. Ultimately, however, it is not just your financial savings that are important, because using the rainwater from day one is a big win for the environment.

Photos: sidm / archive; Marley