So that the artificially created stream in the garden does not dry out after a while, you must waterproof its base. This also applies to streams made of concrete, because the material draws water and is also attacked by constant moisture. There are various options for this.
How can you waterproof a concrete stream?
To seal a concrete stream, pond liner or liquid film, epoxy resin, sealing slurry or sealing powder can be used. These materials prevent moisture penetration and protect the concrete.
How to waterproof a concrete stream
There are numerous materials that can be used to make streams waterproof. For a concrete stream, you also need materials that keep moisture out. The following four options are often used.
Pond liner / liquid liner
Sealing the concrete stream bed with pond liner is just as practical as it is cost-effective. If you don't want to go to the trouble of carefully laying the film, you can use the liquid version. This can simply be spread or sprayed onto the dried and hardened concrete, is phenol-free and completely harmless to humans and animals - this is particularly important in streams that lead to a fish pond.
Epoxy resin
In contrast to black pond liner, epoxy resin is colorless and seals not only concrete, but also streams made of wood or natural stone. The material is viscous and can therefore be spread easily.
Sealing slurry
Sealing slurry or sealing slurry, as used for sealing house walls and basements, has also proven to be practical for artificial streams. This material is mixed with water, applied to the hardened and dried concrete and then allowed to dry. Sealing slurry is available as a two-component material and can also be used to fill cracks and other damaged areas in the concrete stream bed.
Sealant powder
In contrast to other sealing materials, so-called sealing powder is not applied to the already dried concrete foundation, but instead is mixed into the cement mixture before construction. Using this mortar additive saves you from having to do another step, but has a smaller effect. Sealing powder only reduces water absorption, but cannot make the concrete completely waterproof.
Tip
Making concrete actually waterproof takes a lot of work and requires precision. Instead, you can simply do without the concrete and just line the stream with pond liner. This also allows you more flexibility, after all, once concrete structures have dried, they are difficult to correct again.
