What kind of soil should I use for burying underground drainage pipes?
I am installing an underground drainage system to handle water from my gutter downspouts. We get heavy rains here, so the system is badly needed.
A landscape company incorrectly installed psuedo french drains. (Very long story.) They surrounded and covered the the drainage pipe and immediate surrounding area with ABC, which I guess is normally used as a base for pouring concrete. (I don’t think they compacted it after they spread it. Because when you walk on it you sink. Although there is less sinking when you walk over it as time goes by. This actually cause the area to go out of level with the compaction of the soil.
Unlink the landscaping company who installed the french drains, I will be laying down about an inch of gravel below and above the pipe before I fill in the trench with dirt. So the dirt will go on top of gravel. And more gravel/landscaping rock will go onto of any fill dirt.
Was/is ABC the best material to use for this application? Or would regular fill dirt be better? If it matters, I think the soil around here is high in clay content, so I bet the fill dirt will be as well.
I’m wondering if I can just reuse their ABC when I install my pipes, or if I should haul it away and use fill dirt instead? Maybe a combo or ABC and fill dirt?
Slightly unrelated question, when would you use sand in a landscaping project, other than a top dressing for a play area?
soil and sand is a bad choice because it tends to move right into the black corrugated perforated pipe used in french drains. I find that #2 gravel works very well. It actually works as its own little french drain. when you get about an inch from the surface, top it off with soil so your grass can grow.
you often use sand when you are laying block or stone because it makes leveling easy.
You’re overthinking it. Just cover the pipe with sand, soil, or whatever and keep a downward slope on the pipe or else it could allow stagnant water in and attract mosquitoes. I’d stay with black plastic flexible pipe, non-perforated.
Sand is used for many useful things – excellent base for a building, foundation; a thickener for driveway tar sealcoating to fill in cracks; to counteract heavy clay water retaining soils to allow for good drainage for plant roots.