Good morning all on this snowy morning.
I have been asked to provide a quotation to fill in a ditch which is 300M long and up to 2M deep, it has many land drainage pipes feeding into it so I was wondering if I needed to fit a large plastic drainage pipe to transport the water away down into the stream, or could we just fill it in as it is quite deep. The other idea I was thinking about was putting some french drains in as the area can get quite wet especially at the top of the ditch.
Advice needed really, we have been used to putting in land drainage but this is a little bigger than I have done before, its for a nice estate so want to get it right.
Any help gratefull.
If you simply fill in the ditch you will prevent the land drainage pipes which are running into the ditch from working. This will cause problems with the area of land these land drains are supposed to serve. The best solution would be a larger bore perforated pipe along the full length of the ditch surrounded by clean gravel to act as a carrier drain collecting all water from the individual land drain outlets. The ditch can then be backfilled without risk of later waterlogging.
Be careful if this drain drains land that doesnt belong to your customer - You could accidentally cause thousands of damage to someones land - From the sounds of it it may be a field drain - these can often be linked into a wide system. (In yorkshire we have "internal drainage boards" who oversee land drain networks).
If you make any alterations and a neighbours field becomes waterlogged you and or the owner of the ditch would be liable.
If it must be covered - Lay a large capacity pipe on a gravel bed at the bottom, cover it with 20mm gravel and then membraine and then finally cap with soil. What ever you do, Ensure that it connects upto what ever it drains to. If there is no soakaway, seek pro advice on whether one would work - often in waterlogged - prone sites a soakaway would be useless as the water table is so close to the surface.
Edit - http://www.yorkconsort.gov.uk/about.html explains well what these bodies do - and is the one my family has dealt with.
Many thanks chaps, most helpful and I was hoping that a normal drainage pipe would suit, the owners were talking about a large soilid pipe but I was hoping that was not needed.