We removed the pipe and rinsed it out ready to put back in. While the pipe was out we took the opportunity to check the levels of the drain and found the central section was flat with virtually no fall and the back third was actually running the wrong way. This was rectified and the pipe replaced.
We replaced the pipe and filled the trench with 10mm gravel leaving 6″ for rootzone at the top. The gravel was firmed up before the rootzone was added and heeled in as firmly as possible. The centre on the drain line has been left fractionally proud intentionally to allow for the inevitable settling of material.
The rootzone is a mix of 80% sand and 20% soil which will allow water to drain through to the gravel but at the same time hold on to enough moisture in summer to avoid the drain lines burning out.
The drain lines were then carefully rolled to smooth out any bumps.
It is important to remember that the material used in the drain lines is completely different to the rest of the green. As a result the drain lines will always be visible to a degree.
What we have now however is a functioning drainage system which can be added to over time creating a lattice of extra channels which will quickly and efficiently remove surface water.