What is a Spoon Drain in Residential Construction

Today I’m talking about spoon drains, why we use them to improve drainage around a house site and what a spoon drain looks like.

Video Transcript

G’day this is Matt Cornell from Cornell Engineers.

Today I want to talk about “What is a spoon drain?” and I’ll give you a detail for a spoon drain.

What is a Spoon Drain

So a spoon drain is a concrete drain formed in line with the ground surface and its purpose is to collect stormwater before
it can soak into the ground.

Stormwater falling on the ground beside the spoon drain is directed towards the spoon drain and the bottom of the spoon drain then is sloping and takes the water away before it can soak into the ground.

So this is a concrete spoon drain.

Its width, when we specify it, is about a meter wide.

The thickness of the concrete is somewhere between 80 to 120 millimeters deep and the thickness around the edge is deeper because we need the shape of the spoon drain is maybe 120 to 150 millimetres.

The reinforcement we use is fairly light reinforcement. In Australia, we’d probably use an SL 72 which is seven millimetre bars at 200 millimetre centres in both directions.

A spoon drain, because it’s concrete and because concrete shrinks, is going to need something to control the cracking. At about 2 metre centres we’re going to specify tool joint just so the concrete has somewhere to crack neatly without causing any alarm with uncontrolled cracking.

So that’s a concrete spoon drain but sometimes we also specify a spoon drain just in the ground which is just a natural overland where, when it rains, water falls to the middle and then can drain sideways.
Normally we’ll set these up to collect stormwater before it can soak into the ground carry it along in the spoon drain discharge generally clear of a building downstream of a building.

The reason we like spoon drains over box drains for example or grated drains is that they’re a lot easier to keep clean.

Any leaf litter that falls in this area or dirt is fairly easy to keep clean and a lot of the time just rainwater, stormwater will wash a lot of that debris away compared to grated drains can fill up with rubbish, with leaf litter, with dirt and it’s a lot harder to maintain so we like spoon drains because they’re just easier to maintain. They’re not really something that needs to be maintained.

Spoon Drains vs Ag Drains

The reason we like them, well in fact, the other kind of drain that we talk about a lot is agricultural drains and these are ag pipe drains inside a gravel trench.

These are a different kind of drain and we don’t really use Ag drains where we have water already on the surface.

So this (spoon drain) is really good for surface water, taking away surface water before it can soak into the ground.

An ag-drain, on the other hand, is really good for collecting water that’s already soaked into the ground – maybe on a neighbor’s property or from uphill somewhere.

Water that’s already in the ground. It’s great way for collecting water that’s already in the ground and taking it away.

Thank you for Joining Us

I’m Matt Cornell. This has been our quick talk about spoon drains with a spoon drain detail. I hope you were able to take something away from this.

Thank you.