Posted: Mon May 05, 2008 6:08 pm
Hi,
I need to install a new lawn on poor draining ground made up of heavy clay. They want the lawn to be well drained. I plan to do the following:
1. Rotovate the soil with a heavy duty rotovator whilst mixing in a fair bit of sharp sand.
2. Dig trenches (1.5m apart) to put in collector drains (1.2 metres deep at lowest point, with the whole trench filled with filter material, with perforated land drain at the bottom, and the whole thing wrapped in filter material).
3. Cover the whole area with 6 inches of good top soil.
4. Turf it.
Does this sound ok? The owner wants us to go over the top to ensure it drains well. All the perforated land drains will be draining onto low land, so there will be no problem with soakaways etc. What size filter material should I use to fill the trenches (gravel or larger)? Also, will I need to compact the trenches to ensure they don’t settle later and cause dips in the lawn? If so, do I compact over the trenches, but won’t this crush the land drain at the bottom of the trench? What else can I do to ensure the lawn doesn't 'settle' later and become uneven?
The other thing I thought about is to dig the land over with a mini-digger (whilst mixing in sharp sand) to improve the drainage of the lower layers of soil as opposed to just the surface layers using the rotovator. Do you think this is worth doing or will a rotovator be sufficient?
Many thanks for any advice.
Ramsey
I need to install a new lawn on poor draining ground made up of heavy clay. They want the lawn to be well drained. I plan to do the following:
1. Rotovate the soil with a heavy duty rotovator whilst mixing in a fair bit of sharp sand.
2. Dig trenches (1.5m apart) to put in collector drains (1.2 metres deep at lowest point, with the whole trench filled with filter material, with perforated land drain at the bottom, and the whole thing wrapped in filter material).
3. Cover the whole area with 6 inches of good top soil.
4. Turf it.
Does this sound ok? The owner wants us to go over the top to ensure it drains well. All the perforated land drains will be draining onto low land, so there will be no problem with soakaways etc. What size filter material should I use to fill the trenches (gravel or larger)? Also, will I need to compact the trenches to ensure they don’t settle later and cause dips in the lawn? If so, do I compact over the trenches, but won’t this crush the land drain at the bottom of the trench? What else can I do to ensure the lawn doesn't 'settle' later and become uneven?
The other thing I thought about is to dig the land over with a mini-digger (whilst mixing in sharp sand) to improve the drainage of the lower layers of soil as opposed to just the surface layers using the rotovator. Do you think this is worth doing or will a rotovator be sufficient?
Many thanks for any advice.
Ramsey