When adding gravel to a yard feature for drainage, use angular stones between 0.5 and 1.5 inches large. #3 crushed stone and #57 crushed stone are both ideal for this use. Avoid using round gravel, such as pea gravel, since it will compact and prevent drainage. Similarly, sand does not make a good drainage bed. Gravel is the best choice for drainage ditches, paths, and driveways.
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What Kind of Rock is Used For a Drainage Ditch?
The best type of rock to use for a drainage ditch is #3 crushed stone. It can be purchased from most hardware stores and gravel wholesalers. #3 crushed stone is between 0.5 and 2 inches in size. This makes it ideal for drainage ditches with or without a pipe.
- #3 crushed stone is the best choice for drainage ditches.
- You can find #3 crushed stone at hardware stores or directly from wholesalers.
- Use #3 for both pipeless drains and french drains.
#3 crushed stone is great to use when constructing a french drain. By laying a layer of gravel beneath the perforated pipe, then surrounding the pipe with additional gravel, you allow for proper drainage and prevent a clogged french drain.
Is Crushed Gravel Good For Drainage?
Crushed gravel, sometimes referred to as crushed stone, is excellent for providing drainage. The best type of gravel to use is one that is made up of angular stones. Smooth stones will interlock tightly and drain poorly. #3 and #57 crushed gravel are both excellent choices for most drainage needs.
- Crushed gravel is one of the best choices for drainage.
- Use #3 or #57 crushed stone for your drainage needs.
- Select an angular crushed gravel—smooth stones drain poorly.
- Gravel between 0.5 and 1.5 inches is the best choice for drainage.
Make sure you choose a grade of gravel that is between 0.5 and 1.5 inches in size. Gravel that is too small will lock tightly and make drainage difficult. Very large stones can be difficult to work with and often form an unstable, shifting surface.
Is #57 Gravel Good For Drainage?
#57 crushed stone is an excellent choice for drainage material. The individual stones in #57 gravel are about 0.75 inches in size. This is large enough to allow drainage but small enough to form a solid driveway or path.
- #57 crushed stone is great for paths, driveways, and runoff trenches.
- When creating gravel driveway, begin with #3 crushed stone, then pour #57 on top.
- #3 crushed stone is best for in-ground drainage trenches, but #57 can be used as a substitute.
For large projects, such as a gravel driveway, pour a 3–4-inch deep layer of #3 gravel. Then, top it off with 2–3 inches of #57 gravel. This provides excellent drainage. You can use #57 gravel for paths and small runoff drains. For larger and more complex drains, such as a french drain, we recommend #3 crushed stone. It’s slightly larger than #57 and provides great drainage for belowground applications.
Will Water Drain Through Pea Gravel?
Pea gravel is notoriously bad at providing drainage. Because the individual stones of pea gravel are rounded, pea gravel is prone to packing together to form a solid mass. This prevents water from draining. A trench, driveway, or path where pea gravel has been used is prone to flooding and washouts.
- Pea gravel will compact and trap excess water, causing flooding.
- Do not use pea gravel for drainage trenches or areas that need to shed water.
- For drainage purposes, begin with a layer of gravel that is made of angular stones.
While pea gravel has uses as decorative gravel, it’s not useful for drainage. Instead, choose angular gravel, such as #57 crushed stone. Abnormal, angular-shaped gravel won’t compact together. The spaces between the stones allow water to drain away.
What is Better For Drainage: Sand or Gravel?
Gravel layers provide much better drainage than sand. A layer of medium-sized angular gravel will allow water to flow downhill. On the other hand, sand will pack solid and trap water. If you use sand instead of gravel, your ditch, driveway, or trench will flood or be destroyed by washouts.
- Gravel is far better at providing drainage than sand.
- Sand grains will interlock and form a barrier that prevents drainage.
- If you level a driveway or path with sand, leave several inches so you can add base gravel on top of the sand.
If you use sand as a leveling layer for a driveway or path, allow room to pour 3–5 inches of gravel on top of the sand. This deep layer of gravel will carry water away safely. Too much sand will disrupt the water flow and cause flooding.
How Do You Use River Rock For Drainage?
If you are creating a creek bed, swale, or garden feature, you can use river rock for drainage. However, river rock is not a good choice for a surface that you will walk or drive on. River rock is slick and does not settle to form a solid base for foot or vehicle traffic. It is best used for decorative purposes.
- River rock is best used to provide proper drainage to creek beds and open trenches.
- Do not plan to use river rock for any surface that will be asked to handle foot traffic or vehicle traffic—it doesn’t form a stable surface.
- To prevent weeds from growing through river rock, pour drainage gravel, then top it with river rock.
Because river rock does not form a firm bed, unwanted weeds and plants may grow through river rock installations. One of the best ways to prevent this is to lay a base layer of #57 drainage gravel. Then, top the gravel with decorative river rock.
What Size Stone is Best For Drainage?
- When it comes to planning for water runoff, the best types of drainage gravel are:
- #3 Crushed Stone: Best for drainage ditches such as french drains. Also used for a base when constructing a gravel driveway.
- #57 Crushed Stone: Best for aboveground areas that require good drainage, such as paths and runoff trenches. Great topping for gravel driveways that have a #3 crushed stone base.
By using the larger #3 crushed stone for serious drainage and implementing #57 crushed stone for smaller projects, you’ll get good drainage every time. Just make sure to grade your trenches so water flows away. With these tips, you’ll upkeep your garden, yard, and driveway flood-free.