How do French Drains Work

How do French Drains Work
French drains are a type of drainage system, that have been used since ages due to their convenience in moist and damp areas of houses such as basements. Here are we explain, how do French drains work and also some of their uses.
Gardenerdy Staff
Last Updated: Jun 23, 2018
French drains are a hit since 1859 and are the simplest ways of discarding sewage and water picking it up from one area and taking it to the other. It is a downward sloping trench filled with gravel, which prevents erosion, and drains the water from one area to another.
These drains have a simple basic mechanism of working, but there have been many minor refinements over the years. There are many solutions along with French drains, the first being, that it is used to divert water from behind a retaining wall to a garden irrigation system, which is also done to protect a home's foundation from water damage.
Working Mechanism
The word "French drains", have nothing to do with France. It was framed because of a farmer named French, who found this technique of drainage about 150 years ago in New England. It is built in the form of a narrow ditch filled with gravel, sand, and stones to funnel the water into a drainage pipe underneath.
These pipes are made out of PVC with small perforations that allow the water to seep in. There is also a filtration fabric which is placed on top of the pipe to keep dirt and other debris from clogging the holes. The pipes can also be connected to a gravity drain or a sump pump to take care of the excess ground water runoff.
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Now, that you know how they are made, how they work can also be easily understood. Scroll further for that information.
✤ The reason these drains are built inside the ground is due to few drainage problems. If the area has a lot of water in the ground, with lack of sunlight for evaporation, or if the ground doesn't drain well, these setups are used.
✤ In this system, the water is disbursed along various points and by doing this, it pulls the water away from the wet spot. Due to the angled trench, which is sloped away from the wet ground, this water is transferred to another area. This is a very easy method of building a French drain.
✤ The gravel and sand that is filled in the slopping trench drains down the water quicker than dirt, which can get clogged in the pipes. If the area has too much water, the pipe is placed in the trench with gravel below and above it. This way, the pipe acts as a storage area for excess water and drains it whenever required.
✤ The holes on top of the pipe, are the means by which the water gets into the pipe, and is also the way to remove water more quickly from the surface area. When the water enters the pipe, it is transported down the slope to the bottom through the gravel and then out through the holes. Excess water is collected in ponds or more drains.
✤ Also, if a particular area receives a lot of rain and faces standing water issues, these setups are the best choice to remove the extra water out of it. For this reason, a pipe is placed, up to the surface that does the job of pulling water away rapidly and brings it down to the slope into a French drain.
✤ With the help of a filter that is placed on the surface, the debris does not get down into the lower pipes and the rest of the system works normally and you don't suffer from a clogged drainage. These are the easiest way to drain extra water.
With this useful information about French drains and how they work, the idea must be clearer to you now! So, if you are facing drainage water problems, it is absolutely perfect to get French drains installed.