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.
Add and compact 3 inches of coarse drainage gravel in the trench. Place the perforated pipe on top of the gravel in the trench.
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.
One of the most important parts of the French drain is the gravel because it enables water that has seeped through the ground to be taken away down the slope of the drain. 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.
One of the biggest French drain mistakes is not lining the trench with drainage fabric. A drain requires a fabric lining to act as a soil separator, in order to prevent any dirt and debris from getting into the drain's gravel lining so water can flow freely.
An outdoor French drain is a trench you cover in rocks. It's connected to pipes to guide water away from your home. The first part of French drains is the elevated or higher end, referred to as a drain field. The drain field is where the groundwater or excess surface water enters the drainpipes.
For water to flow freely, there needs to be adequate spacing between the rocks. Pea gravel is not a good choice to use for a French drain because the size of the rocks are too small. It also compacts more easily, which prevents proper use of the drainage system.
Description: #57 Stone is a popular lime rock gravel rock choice for drainage, driveways, and erosion control base material. Because of its cheaper cost, it is often used in french drains and in parking lots.
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.
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.
Best Landscape Rock for Drainage: Pea gravel is ideal, providing good drainage while enhancing the visual appeal of your garden paths or flower beds.
Installing a French drain costs $500 to $18,000, with a national average of $9,250. 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.
8 cons of French drains
May require regular maintenance. Care must be taken not to hit utility lines when digging for installation. Installing them may involve digging up your yard or even pavement. If the pipe gets clogged, it can be difficult to find and fix the problem area on your own.
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.
The stone should be no less than ¾” and dense (we suggest Granite, or River Gravel) so it will allow good water flow.
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.
One truckload of this rock is roughly equal to 10 to 12 cubic yards or 16 tons and may cost around $800, although prices can fluctuate. Dirt Connections currently offers this type of stone in increments of half a truckload.
When it comes to landscaping to divert water from the house, gravel is an excellent option. It is vital to note the benefit of rocks around the house for drainage. Ensure the gravel bed does not slope towards the foundation.
Gravel allows water to filter through and improves drainage. Your layer should be around 3 inches deep. What kind of gravel should you use for a French drain? Avoid pea gravel and crushed rock and opt for round, washed rock ½ to 1 inch across.
Because it's small, pea gravel will move easily if not edged properly. If you're going to add it to a walkway or a flower bed, be sure that you have concrete blocks or landscape trim set up to keep the pea gravel in place.
Among 15 choices, these Pea gravel Landscaping Rock have the highest satisfaction ratings with Lowe's customers. While these might be the highest rated, what you choose should fit your needs, so consider additional features such as Brand, Size and Color/Finish Family when making your selection.
If you have a problem area where water tends to pool, a trench drain may be the best option. If you want a drainage system that is less visible or installed around the perimeter of yo French drains are long-buried trenches containing a perforated pipe enclosed by gravel.
If installing the drain involves diverting a stream or affecting a wetland, you likely need a permit to move forward. Generally, a small French drain on your property that doesn't change the flow of runoff entering and exiting your yard won't need a permit.
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.