For heavy-duty drainage applications like French drains and retaining walls, crushed stone is better. Its angular, jagged edges interlock to create a highly stable base, while the irregular shapes leave larger voids for water to move through without the material shifting.
Its angular, porous construction lets water pass between the stones unhindered. This effective water flow lessens the possibility of floods and helps minimize water collection. Because crushed stone provides better drainage than other materials, it is a preferred choice for many drainage uses.
Crushed stone costs $20 to $115 per cubic yard, while gravel ranges from $15 to $250 per cubic yard depending on the stone type. Your choice between crushed stone and gravel depends on your project needs: industrial applications suit crushed stone, while aesthetic landscaping calls for natural gravel.
The best rock for drainage is washed, smooth round rock (ranging from 34three-fourths34 to 112 inches) or 3/4-inch crushed washed gravel. These stones create large, open voids that allow water to flow freely without the material compacting over time.
French drains are a low-cost option for dealing with surface water. These systems consist of a trench which houses a perforated PVC pipe. The pipe is secured in a mesh sock to keep dirt out, that is covered with gravel.
The Golden Rule of Drainage is: “Drain only what is necessary for good crop growth and trafficability, and not one drop more.” “Conservation drainage” goes further, incorporating approaches and practices to minimize the environmental impacts on the downstream environment and ecology.
Yes, you can dig a hole and fill it with gravel to create a drainage system (often called a dry well or a vertical French drain). However, to ensure it works and doesn't quickly clog or fill with mud, you need to follow a few specific steps.
For a standard residential drainage project or French drain, your trench should be excavated 12 to 24 inches deep and 6 to 12 inches wide. The gravel should extend at least 3 to 4 inches beneath your perforated pipe and cover the top of the pipe by at least 4 to 6 inches.
The ideal drain rock size typically ranges from 𝟑𝟒 𝐢𝐧𝐜𝐡 to 𝟏𝟏𝟐 𝐢𝐧𝐜𝐡𝐞𝐬 in diameter. This size creates large voids between the stones to maximize water flow while preventing the rock from clogging perforated pipes.
Generally, medium to large rocks (1/2" to 2") are better for drainage. They create larger "void spaces" (gaps) between the stones, allowing water to flow rapidly without becoming clogged.
The short answer is $10 to $75 per ton depending on the type and whether delivery is included, but there's more to consider when budgeting your project. Most homeowners pay between $30 to $60 per ton for standard driveway gravel before delivery costs.
Salt on a gravel road causes maintenance problems as the road begins to thaw out, often making conditions worse. As the salt melts the snow/ice, it causes the salt and water solution to penetrate into the road surface. This causes the road surface to break up and loosens the previously hard packed surface.
Crushed stone is a mechanically processed rock with sharp, angular edges that lock together, making it ideal for stable driveways, structural bases, and heavy-traffic areas. Gravel is a natural, river-weathered rock with smooth, rounded edges. Because gravel stones act like marbles and shift easily, they are best suited for loose-fill landscaping and drainage.
Using gravel allows the water to flow freely and seep down through into the land drain where the water is carried to a discharge point or a soakaway crate. Fill the trench up with a minimum layer of 300mm gravel backfill to a depth of about 150mm from the surface.
Typically, a layer of rock at least 2-3 inches deep is effective in preventing most weed growth. This thickness provides a solid barrier that suppresses weeds while allowing for proper drainage.
For a 10x10 area, you will need approximately 1 cubic yard (or about 25 to 27 cubic feet) of pea gravel to achieve a recommended 3-inch depth. This is enough to cover the space effectively without the ground showing through.
3/4” Washed Gravel Stone is widely used for drainage solutions, including septic systems and French drains, due to its efficient water flow capabilities. It also serves as a decorative gravel for pathways, garden beds, and around foundations, providing both functionality and aesthetic value.
On average, installing a French drain costs between $10 and $65 per linear foot. The price depends on where you live, the type of soil, and the complexity of the job. For a typical 100-foot French drain, most homeowners spend between $1,000 and $6,500, covering materials, labor, and excavation.
Depth in permeable soils
In soils where the drains control the depth of the water table, deeper drains allow the spacing between drains to be increased. Drain depths in such soils are typically 1.2–1.5 metres.
Pea Gravel Is the Best Overall Choice for Drainage
It's made up of small, smooth stones that are typically the size of a pea. It has a unique size, shape, and loose structure that lets water flow through it easily.
For a French drain, the holes in your perforated pipe should face down (between the 5 and 7 o'clock position). This allows water that pools at the bottom of the gravel trench to easily rise up and enter the pipe through hydrostatic pressure, rather than waiting for the water level to submerge the entire pipe.
Yes, a 2-foot retaining wall should have drainage to ensure long-term stability and prevent failure. While small, 2-foot walls can still trap water and build up significant hydrostatic pressure, leading to bowing, cracking, or tipping.
Gravel that hardens like concrete is typically a mixture of crushed angular stone and fine rock dust. When compacted, the fine powder acts as a binder, locking the larger stones into a solid, durable surface. Common varieties include Crusher Run, Decomposed Granite (DG), and Crushed Concrete.
Yes, you should put 3–4 inches of gravel (angular crushed stone or pea gravel) under a drainage pipe to create a stable, sloped bed, prevent the pipe from settling into the soil, and allow water to flow freely underneath, which helps prevent freezing and clogs.
To improve soil drainage, mix in coarse inorganic materials like perlite, pumice, or horticultural sand to create larger air pockets. For garden beds, incorporate organic matter like compost to loosen heavy clay and help roots breathe.