Best drainage for new lawn courtyard on clay?

Question

Hi. We recently had some sandstone blocks laid (ag pipe was installed behind wall) to retain soil at the back of our block for a recently built house. We now have an enclosed courtyard. There are a few stormwater pit connections to choose from. The courtyard has a lot of clay and water sits on top. Our intention is to lay a lawn once we have prepared the ground. What drainage options do you think might work best? I have heard about French type drainage but not sure if it will be suitable. I would appreciate the communities advice.

JacobZ · Answer

Hi @rex_4321,

In a lawn, French drains are typically installed in the lowest areas where water naturally collects, or around the perimeter if runoff is coming in from the surrounding ground. In your situation, having a french drain around the perimeter would make the most sense to me as it would collect any water running down from the stairs and higher area, and any ground water heading towards the house slab.

Channel drains could also be added along the outside of the house slab, like in Eric's render, in case there is excess surface water.

The french drains, and any channel drains should both run directly to the stormwater pipe independent of each other, but as @Dave-1 has noted, any connections made to your stormwater pipes must be done by a licenced plumber. They would likely be able to advise the best approach.

Let me know if you have any further questions.

Jacob

Dave-1 · Answer

Good Evening @rex_4321

Just a note that you will need a plumber to connect the ag pipe to the stormwater pipe.

I like the idea of the French drain probably closer to the house slab then the middle, you want it to drain but not exhaust the water in the yard. A sketch always helps me  solidify what I want and also what can work :)

Dave

rex_4321 · Answer

Hi @EricL and @Dave-1 many things for the advice and the fancy ai render. What configuration would you suggest for laying the french style drain? Lay it through the middle and ensure it flows to the grate ? Would it be better to connect the ag pipe to the storm water connections directly as that will have a lower connection point and it will be easier to create a slope for the water to drain to ? I will try and create a 2D plan based on what has been discussed so far.