French drains on a track - Will they work?
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I have a track about 60m long that leads to my house. It's constructed with a consolidated aggregate base topped with quarrydust and scalpings as a surface binder. The problem I have is that heavy rains lead to water running down the track and flooding the path at the front of the house - I'm planning to do some work here replacing flags anyway and I'll be putting a french drain along the path (I'm fortunate enough to be right on the shore so I've no issues with disposing of surface water). I would also like to put something across the track and along the lowest side to remove surface water. Would a french drain work here?
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French drains are a waste of time and money. They are a classic example of a technology that was fine for thousands of years because there was no alternative, but which has been superceded by advances in geotextiles.
The big problem with French drains has always been that they silt-up, and given that your site description reports a surface of quarry dust, silting-up is likely to happen at a faster rate than normal on this project. Which is why I would recommend a 'proper' collector drain as shown here. Note the two key 'upgrades' compared to an olde-worlde French drain: the presence of a perforated pipe at or near the base of the trench, and the use of a permeable geotextile liner. The pipe maintains an open flow channel for times of really heavy precipitation while the geotextile prevents silting and keeps out the tree roots.
If you're going to build a drain, it might as well be one that won't balls-up in 5-10 years time!
The big problem with French drains has always been that they silt-up, and given that your site description reports a surface of quarry dust, silting-up is likely to happen at a faster rate than normal on this project. Which is why I would recommend a 'proper' collector drain as shown here. Note the two key 'upgrades' compared to an olde-worlde French drain: the presence of a perforated pipe at or near the base of the trench, and the use of a permeable geotextile liner. The pipe maintains an open flow channel for times of really heavy precipitation while the geotextile prevents silting and keeps out the tree roots.
If you're going to build a drain, it might as well be one that won't balls-up in 5-10 years time!
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The collector drain is what I actually meant - sorry about the confusion, I'm not really that up on the terminology!
I intended to dig a trench across the track in two places one just before a 90 degree turn where the track comes off of the public road (I get water along this part) and one after where the track falls towards the house itself where I get some additional water from a field above, link these trenches with a trench along the lower, inside curve of the bend, and dig a further trench on the lower side of the track where water would accumulate down to the house and link into the drainage I'm planning to run under the flags there - it will eventually discharge onto the shore in front of my house (part of my land too).
I was going to use a geotextile barrier to stop silting up and a 100mm perforated plastic pipe as well. Would it be worth bringing the end of the pipe to the surface at the highest point to enable it to be flushed through if necessary?
I intended to dig a trench across the track in two places one just before a 90 degree turn where the track comes off of the public road (I get water along this part) and one after where the track falls towards the house itself where I get some additional water from a field above, link these trenches with a trench along the lower, inside curve of the bend, and dig a further trench on the lower side of the track where water would accumulate down to the house and link into the drainage I'm planning to run under the flags there - it will eventually discharge onto the shore in front of my house (part of my land too).
I was going to use a geotextile barrier to stop silting up and a 100mm perforated plastic pipe as well. Would it be worth bringing the end of the pipe to the surface at the highest point to enable it to be flushed through if necessary?
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Flushing - bring up the pipe-end at 45° and fit it with rodding-eye cap, as shown at the right-hand end of this drawing
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