Page 1 of 2 12 LastLast
Results 1 to 20 of 28

Thread: Drainage Agpipe

  1. #1
    Junior Member
    Join Date
    Jun 2011
    Posts
    208
    Thanks
    23
    Thanked 26 Times in 14 Posts
    Rep Power
    110
    Reputation
    140

    Default Drainage Agpipe

    I seem to have a ground water problem, Im on a slight slope so already started digging trenches for Agpipe but need some advise..

    My father believes I should use plain agpipe with no filter, wrap it in newspaper and sandwitch it between 19mm (3/4") Drainage Scoria within the trench.

    But for me after researching on the internet I proper prefer to perhaps line the base of the trench with newspaper to filter small particles, then use socked (geofrabic) agpipe sandwitch between the scoria within the trench..

    Whats the best method of laying down agpipe? I have heaps of scoria so I guess I can widen the filteration area created by the scoria.

    I have orange clay about 2 foot down, my soil isn't really sandy I could probably get away without using the sock but its probably better to use one with sock... not sure which one will clog up faster or if it doesn't make a difference and both will clog up over time ?

    Any help advice welcomed



Look Here ->
  • #2
    Premium Member
    mandc's Avatar
    Join Date
    Jan 2008
    Location
    Gold Coast
    Age
    65
    Posts
    3,656
    Thanks
    1,799
    Thanked 2,404 Times in 1,239 Posts
    Rep Power
    787
    Reputation
    26155

    Default

    My thoughts...which are probably wrong...is that the sock will hasten the clogging of the drainage holes of the agpipe. The holes in the pipe walls are a hell of a lot smaller than the diameter of the pipe so it should not clog..especially if it is on a slope.

    All the agpipe I have ever laid had no sock and 10 years on it still works.

  • #3
    Member
    Join Date
    Jan 2008
    Age
    62
    Posts
    402
    Thanks
    162
    Thanked 148 Times in 95 Posts
    Rep Power
    172
    Reputation
    842

    Default

    I would dig the trench, lay the geotextile in it, lay the pipe, cover the sides and top of the pipe with the scoria then fold the geotextile over the top.

  • The Following User Says Thank You to homebrew041 For This Useful Post:

    darkage (28-11-11)

  • #4
    Senior Member
    weirdo's Avatar
    Join Date
    Jan 2008
    Posts
    5,458
    Thanks
    4,638
    Thanked 3,134 Times in 1,632 Posts
    Rep Power
    0
    Reputation
    29582

    Default

    Just fill all the trenches with gravel

  • #5
    Senior Member
    fandtm666's Avatar
    Join Date
    Jan 2008
    Posts
    5,116
    Thanks
    141
    Thanked 579 Times in 250 Posts
    Rep Power
    957
    Reputation
    32227

    Default

    1: dig trench
    2: lay matt
    3: put some gravel
    4: lay pipe that has the sock on it
    5: cover with gravel
    6: lay matt
    7: finish filling with soil


    well thats how i used to do it when i was getting paid as a plumber

  • The Following 2 Users Say Thank You to fandtm666 For This Useful Post:

    darkage (28-11-11),Hakko (29-11-11)

  • #6
    Senior Member
    Godzilla's Avatar
    Join Date
    Jul 2008
    Location
    Melbourne
    Age
    55
    Posts
    12,650
    Thanks
    15,902
    Thanked 7,008 Times in 3,580 Posts
    Rep Power
    2063
    Reputation
    75253

    Default

    We had the same problem at my fathers house, on a slope with a soil swimming pool under it that was rotting the posts.

    Deep trench across the high point and the sides.

    Lined the bottom of the trench and house side with black plastic to stop water that was missed penetrating through.

    Crushed rock base, lay pipe, cover in crushed rock.

    Put 10cm soil and grass back over the top.

    The soil under the house dried out quickly, we tried to dig out a basement to store things a few years later, it was so dry and hard the pick use to just bounce off.

  • The Following User Says Thank You to Godzilla For This Useful Post:

    darkage (28-11-11)

  • #7
    Junior Member
    Join Date
    Jun 2011
    Posts
    208
    Thanks
    23
    Thanked 26 Times in 14 Posts
    Rep Power
    110
    Reputation
    140

    Default

    Thanks all! I like diavalo's method...

    I guess everyone has their own method and I was a little hangup on with to sock or not I guess more layers of filteration the better in a way..

  • #8
    Junior Member
    Join Date
    Jan 2008
    Posts
    196
    Thanks
    47
    Thanked 43 Times in 19 Posts
    Rep Power
    153
    Reputation
    247

    Default

    Quote Originally Posted by diavalo13666 View Post
    1: dig trench
    2: lay matt
    3: put some gravel
    4: lay pipe that has the sock on it
    5: cover with gravel
    6: lay matt
    7: finish filling with soil


    well thats how i used to do it when i was getting paid as a plumber
    Thats the way to do it!

  • #9
    Junior Member
    Join Date
    Jun 2011
    Posts
    208
    Thanks
    23
    Thanked 26 Times in 14 Posts
    Rep Power
    110
    Reputation
    140

    Default

    One quick question.. would the sock actually clog up faster since it looks like it would offer finer particule filtration than the actual agpipe but then again it has a large surface area for the water to get in..

    Just my father kept on warning me that the dust from the scoria might block up the sock..

    but then again my father did say just use one bag on my satellite dish pole and thats suffering from slight movement from boggy soil
    Last edited by darkage; 28-11-11 at 11:13 AM.

  • #10
    Junior Member
    Join Date
    Jun 2011
    Posts
    208
    Thanks
    23
    Thanked 26 Times in 14 Posts
    Rep Power
    110
    Reputation
    140

    Default

    Quote Originally Posted by Godzilla View Post
    Lined the bottom of the trench and house side with black plastic to stop water that was missed penetrating through.

    The soil under the house dried out quickly, we tried to dig out a basement to store things a few years later, it was so dry and hard the pick use to just bounce off.
    I like the usage of black plastic... I might add in that touch.. my lowest point of my house is like a swimming pool too. I have concrete posts.

    on the weekend noticed some pooling of water on the outside. Next thing I knew I dug a 1.5 metre channel outside to drain the water out. I think I bucketed out 120 litres.. saturday was like tropical monsoon rain..

  • #11
    Administrator
    mtv's Avatar
    Join Date
    Apr 2008
    Posts
    17,808
    Thanks
    5,195
    Thanked 11,536 Times in 5,682 Posts
    Rep Power
    4060
    Reputation
    166411

    Default

    I agree with diavalo13666's method.

    Rowville is renowned for poor drainage.. after all, it is reclaimed swamp land.

    It's even reflected in the name... row-ville.

  • #12
    Member
    Join Date
    Jan 2008
    Age
    62
    Posts
    402
    Thanks
    162
    Thanked 148 Times in 95 Posts
    Rep Power
    172
    Reputation
    842

    Default

    I think its still better to put the aggpipe at the very bottom of the trench.
    If you place say 50mm of scoria under the pipe your soakage trench will have to fill with more than 50 mm of water before the pipe can start to work.
    Consider your trench to be maybe 250mm wide and thats a lot of water that will be soaking into the subsoil before your aggpipe will do anything? If you could put enough fall in the trench it wouldn't be an issue, but in that case you you could do as wierdo states and just fill it with the gravel.

  • #13
    Junior Member
    Join Date
    Jun 2011
    Posts
    208
    Thanks
    23
    Thanked 26 Times in 14 Posts
    Rep Power
    110
    Reputation
    140

    Default

    Quote Originally Posted by mtv View Post
    Rowville is renowned for poor drainage.. after all, it is reclaimed swamp land.

    It's even reflected in the name... row-ville.
    haha! lol! I better start building my boat instead. At least Im half way up a hill.. other areas are pretty bad when it really pours..

    Yeah homebrew you have a valid point.. probably makes more sense with agpipe with sock to sit directly ontop of matt then layer gravel ontop.

  • #14
    Senior Member
    Godzilla's Avatar
    Join Date
    Jul 2008
    Location
    Melbourne
    Age
    55
    Posts
    12,650
    Thanks
    15,902
    Thanked 7,008 Times in 3,580 Posts
    Rep Power
    2063
    Reputation
    75253

    Default

    BTW, what is the sock? We never used one.

    I remember we used a variety of stone sizes, around the pipe was the finest (smallest) size rock and the further away from the pipe we went, the larger the crushed rock size was used.

    It was so long ago, i remember my father telling me it was to filter the water of large particles by going from large rock (20 cent piece size) to small fine crushed rock.

    That was over 25 years ago, still works fine, bone dry, hard as a rock under the house.

  • #15
    Senior Member
    weirdo's Avatar
    Join Date
    Jan 2008
    Posts
    5,458
    Thanks
    4,638
    Thanked 3,134 Times in 1,632 Posts
    Rep Power
    0
    Reputation
    29582

    Default

    You'd be surprised how well a trench just filled with drainage gravel works.
    It will need a bit of fall to work successfully (the more the better) but that's no different with pipe.
    I dug a trench 300 wide by about 500 deep over a distance of about 35 meters to catch overland flow of my uphill neighbours.
    No fancy geo fabric or socks or pipe for that matter.
    Been there for 15 years and still works well.

  • #16
    Junior Member
    Join Date
    Jun 2011
    Posts
    208
    Thanks
    23
    Thanked 26 Times in 14 Posts
    Rep Power
    110
    Reputation
    140

    Default

    Quote Originally Posted by Godzilla View Post
    BTW, what is the sock? We never used one.
    Plastic netting around pipe... can be purchased that way. Just like a sock


  • The Following User Says Thank You to darkage For This Useful Post:

    Godzilla (29-11-11)

  • #17
    Junior Member
    Join Date
    Jun 2011
    Posts
    208
    Thanks
    23
    Thanked 26 Times in 14 Posts
    Rep Power
    110
    Reputation
    140

    Default

    Quote Originally Posted by weirdo View Post
    You'd be surprised how well a trench just filled with drainage gravel works.
    It will need a bit of fall to work successfully (the more the better) but that's no different with pipe.
    I dug a trench 300 wide by about 500 deep over a distance of about 35 meters to catch overland flow of my uphill neighbours.
    No fancy geo fabric or socks or pipe for that matter.
    Been there for 15 years and still works well.
    Actually I find that not too hard to believe... Bunnings plumber said why put down agpipe when it will fall from the bottom of the pipe.. I've had my trenches not filled in for 2 months with the some off cut agpipe I've found and I do see the water flow down to the lowest point like a mini stream.. If just filled with gravel, I take the lowest point would be grated drain with some fine filter over it (panty hose perhaps) then cover with large gravel?

  • #18
    Premium Member

    Join Date
    Jan 2008
    Location
    Central Tablelands of NSW
    Age
    76
    Posts
    13,824
    Thanks
    1,242
    Thanked 3,803 Times in 2,523 Posts
    Rep Power
    1741
    Reputation
    56926

    Default

    Your missing the point of drainage, Roof gutters dont need more than a minimal slope to function nor does the Agpipe.
    The whole principle is to remover the BULK volume of water quickly and the gravel just drains away whats left either by soakage or evaporation.
    If you were to flood the Apipe with a fire hose, you would see how very little actualy 'leaks' out of the sides compared to the flow through.

    The 'sock' or earth mat stops both earth and weeds from fouling the drainage but like everything else its not for ever.
    I have large sheets of 'Earth Mat' laid under sections of Railway line (Points) to stop the line 'Pumping' the ballast as trains passed over and 'drawing up' the mud from under the ballast.
    Water drains straight through the mat easily.
    I stand unequivicably behind everything I say , I just dont ever remember saying it !!

  • The Following User Says Thank You to gordon_s1942 For This Useful Post:


  • #19
    Premium Member
    LeroyPatrol's Avatar
    Join Date
    Jan 2008
    Location
    N.E. Vic
    Posts
    15,846
    Thanks
    3,280
    Thanked 4,401 Times in 2,654 Posts
    Rep Power
    1478
    Reputation
    40371

    Default

    When I did all my retaining walls I lined the inside of the wall and the ground behind with black plastic and then laid the pipe on the plastic next to the wall and filled with stones or more like small pebbles that are nice and smooth. The wall hasn't fallen down yet and I used no fancy socks etc.

    Leroy
    XCRUISER HDSR600HD twin sat and terrestrial receiver $OOS *
    XCRUISER HDSR385 Avant - sold out$OOS UltraPlus DVB-T and DVB-S2 tuners $49 Remotes $OOS

  • #20
    Senior Member
    fandtm666's Avatar
    Join Date
    Jan 2008
    Posts
    5,116
    Thanks
    141
    Thanked 579 Times in 250 Posts
    Rep Power
    957
    Reputation
    32227

    Default

    Quote Originally Posted by weirdo View Post
    You'd be surprised how well a trench just filled with drainage gravel works.
    It will need a bit of fall to work successfully (the more the better) but that's no different with pipe.
    I dug a trench 300 wide by about 500 deep over a distance of about 35 meters to catch overland flow of my uphill neighbours.
    No fancy geo fabric or socks or pipe for that matter.
    Been there for 15 years and still works well.
    What you have done there is similar to whats called a TRANSPIRATION trench.

    these are used for places with septics where you dig the trench put in the the half pipe plastic and then fill over with gravel etc.The trench would be dug at 90 degrees to the fall of the land.

    we also used to install these in similar situation to yours.By digging the trench and installing the half pipe would create a empty volume of space>when it rained and the surface water would soak into the soil and flow down to the next property it would reach the trench and fill the empty space created by the half pipe.Now it would sit and slowly seep back into the ground water system.

    Many more suburbs in Sydney are going this way because the stormwater system can not handle all the water and many buildings are cracking because the soil is all drying out so by putting the water back into the ground system it helps 2 fold.

  • Page 1 of 2 12 LastLast

    Bookmarks

    Posting Permissions

    • You may not post new threads
    • You may not post replies
    • You may not post attachments
    • You may not edit your posts
    •