River rock tops the list of the best rocks for installing in French drains. Natural round rocks are ideal because their size and shape allows the water to drain more effectively. It's vital to use washed rock because it has been cleaned of debris and particles, which will help prevent clogging the drainage system.
But which gravel is ideal for a French drain? Hard rocks like washed river rock or granite chips are the ideal gravel for French drains. The gravel pieces should ideally average at least 1′′ wide to provide the best permeability for water to run along.
The stone should be no less than ¾” and dense (we suggest Granite, or River Gravel) so it will allow good water flow. Lime Rock, although inexpensive, is a poor choice for a French Drain because it will begin to deteriorate over time and eventually begin to pack down and restrict flow.
The best material for a french drain is a mixture of clean sand and gravel. This is better than gap graded aggregate. This would be the typical aggregate used in making concrete, but of course without the cement. There is one other possible problem.
Pea Gravel: The Ideal Choice. Pea Gravel's reputation as the best option for drainage stems from its unique properties. These small, rounded stones have high permeability, allowing water to flow through easily and preventing accumulation.
Use River Rocks – Having a dry-creek bed installed to redirect water adds style and is a terrific way to prevent pooling in uneven or low areas. River rock can also be used to create French drains that commonly deliver water to dry wells which hold excess water, allowing them to drain slowly back into the yard.
You would need around 0.72 cubic feet of gravel per foot length of French drain for a typical French drain width of 10 inches and a depth of 12 inches if you're using a 4" drain pipe. On the other hand, you would need around 0.6 cubic feet of gravel if you're using a 6" drain pipe.
Pea gravel is one of the best materials for landscape drainage because its small size allows for outstanding drainage. These rocks are only about ¾ inches in size. Pea gravel is available in a variety of shades, including brown, grey, blue, and red, making it a good choice for a number of different landscapes.
Pour and compact about 3 inches of gravel or landscaping stone along the bottom of the trench. This will act as bedding for the drainage piping.
To prevent this, clean out and snake the French drain once a year. Whether you're performing interior French drain maintenance, basement French drain cleanout, or exterior French drain maintenance, you'll need an electric sewer snake. You can easily rent one if you don't want to buy it.
Clay soil has poor permeability, meaning it doesn't allow water to pass through easily. In such cases, the effectiveness of a French drain may be limited as the water may struggle to drain away from the area efficiently. French drains may not be suitable for areas with high water tables.
Versatile Size: The 1/2 inch to 1 1/2 inch size range of #57 gravel suits various construction and landscaping needs. Effective Drainage: Due to its porous nature, # 57 Stone allows water to flow through, preventing pooling and erosion.
Swales: A Natural Solution
They're a great option if you're looking for a more natural, eco-friendly alternative to French drains. A swale is typically lined with grass or vegetation that helps slow down and absorb water.
If you want to connect the French drainage system to the gutter downpipes from your home, consider using a 4-inch pipe rather than a 3-inch pipe. In heavy rain or bad weather, 3-inch pipes may not be able to cope with the amount of water that comes out of the downpipes flowing through them.
Both crushed stone and gravel serve as excellent drainage materials. Gravel is often used in French drains, septic drainage fields, and other drainage applications, while crushed stone is used in similar applications where a firmer base is needed.
Choice of Materials
Higher-quality materials often come at a higher price but may offer better durability and performance, potentially reducing long-term maintenance costs. The gravel or rock needed for a French drain can range from $10 to $60 per cubic yard, depending on the quality and type.
River rock tops the list of the best rocks for installing in French drains. Natural round rocks are ideal because their size and shape allows the water to drain more effectively. It's vital to use washed rock because it has been cleaned of debris and particles, which will help prevent clogging the drainage system.
French drain depth: About 8 inches to 2 feet deep should be sufficient for many water-diverting projects, though related systems, such as those built around foundations and sub-ground living spaces, as well as the bases of retaining walls, may be deeper.
Bury Drain Pipe in Gravel
In the next step of building a French drain, place the drain pipe on top of a fabric lining. Add gravel until the pipe is completed covered. There should be 5 inches from the top of the gravel to the ground.
The Bottom Line
The best type of fabric for a drainage project such as a drain field or french drain is non-woven geotextile landscape fabric. If you're project requires high strength and also good drainage then a high end combination woven fabric could be suitable for your application.
Firstly, their natural composition allows water to pass through easily. Unlike solid surfaces that can cause water to accumulate, river rocks create a permeable layer that facilitates the movement of water. This is particularly beneficial in areas with heavy rainfall or poor soil drainage.
Landscape rock serves as a highly effective solution for addressing drainage issues by promoting efficient water runoff.
Traditionally, you would fill it with gravel, but you may wonder if you have any alternatives. Could you instead fill it with sand? Yes, you can use sand instead of gravel for your French drain when your project calls for it. It is less effective than gravel, but it can get the job done.
On average, you can expect to pay $10 to $100 per linear foot, or between $500 and $5,000 to have a 50-foot French drain installed. The final price will depend on several factors, including drain type and size, location, labor, and any permits you might need.
Corrugated pipes are a popular choice for French drains. They have a flexible, ribbed design that allows them to bend and conform to the shape of the trench. They're can also be easier to install than PVC pipes, as well as require fewer fittings and couplings to connect.