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lou_spicewood_tx

Planting trees on top of PVC sewer pipe

lou_spicewood_tx
11 years ago

I recently moved into a new house and they planted a live oak directly on top of the sewer pipe for some reason. I don't know how deep the pipe is but I looked at several houses under construction and noticed that the sewer pipe wasn't that particularly deep. Will that eventually cause problems one day? I will eventually take it out anyway since it's too close to the driveway for my liking.

Comments (18)

  • ken_adrian Adrian MI cold Z5
    11 years ago

    city water.. city sewer.. sealed system.. right???

    no septic issues here ...???

    i would consider PVC to be impervious.. for the next millennium or so.. i dont know what a tree could or would do to it ... the connections between pipes literately welds the pieces of plastic together..

    ken

  • lou_spicewood_tx
    Original Author
    11 years ago

    Ken,
    It's a brand new house so no issues at all.

    It looks like they run water line through PVC pipe that runs to the house along the sewer pipe line from the street. I was thinking in terms of expansion over the time from the root system that would put pressure against sewer PVC pipe over the years. Just wondering since the sewer line is right underneath the live oak that they planted a couple months ago.

  • j0nd03
    11 years ago

    If the tree is a recent transplant and moving the oak will spare you from any amount of worry, why is your shovel idle and collecting rust?

    ;)

    John

  • ken_adrian Adrian MI cold Z5
    11 years ago

    again.. i would like to think that modern construction creates an impervious barrier to tree roots ..

    as compared to say late 50's or earlier suburbia... clay pipes packed with oakum.. etc ...

    PVC does NOT expand ... its inert.. chemically bonded thru melting of PVC ...

    i dont really care.. about sewer issues.. thats the cities problem .. i dont know how that connection is made ...

    ken

  • brandon7 TN_zone7
    11 years ago

    If you plan on living in the house for many years, I would get rid of it, or move it, ASAP. The longer you wait, the bigger the job will be. I think your concerns may have some validity down the road (many years from now). Tree roots expand and contract with soil moisture and can do some serious damage in certain cases. Yes, PVC is some pretty tough and somewhat flexible material, so maybe you'd be OK, but why take the chance. You said you would eventually take it out anyway, so I'm not sure there's much else to consider anyway.

  • eahamel
    11 years ago

    Ken, sewer issues on YOUR property are not the city's problem. Since the pipes are PVC, they are much less likely to be damaged by trees than concrete. I have a horror story about that one....

  • lou_spicewood_tx
    Original Author
    11 years ago

    Ken, what about crushing pressure by the expansion of root system over the years? That was what I was wondering about after seeing how shallow the pipes were at the other house when they were installing the pipe from the house to the sewer system at the end of the street.

    Brandon, I was considering replacing sorry looking Live Oak (over planted anyway) with something more desirable but after seeing how shallow the sewer pipes were at the other houses under construction, it got me wondering about it.

    John, I tried pulling it out by hand once we moved in but it would not budge (30 gallon at least?) I figure it's just easier to saw it off at the base and cover it with mulch. Use the wood for fire. :-)

  • Toronado3800 Zone 6 St Louis
    11 years ago

    Right on the pipe is pretty silly. I bet for we have 20 years before crushing or imploding due to pressure is an issue.

    And plastic in a hole like pvc may last a long time but last I remember them space suits in the Smithsonian were behind glass and it seems the plastic in my decade old Lincoln is biodegrading nicely.

  • WxDano
    11 years ago

    All you need is one bad seal on a joint and you are done. That is were roots penetrate most often. If it were me I'd find somewhere else.

  • whaas_5a
    11 years ago

    Around here PVC sewer pipe is buried well below the frost line so roots would never be an issue in regards to pressure.

    You could contact the building inspector or public works and just ask what the code is for depth. Tree roots typically aren't going to be deeper than 24" depending on the soil and how oxygen rich it is. However oaks as you know reach further than most.

    If anything I'd be more concerned if they need work on, re-route, tie-into, etc. If they have to do this is quite possibly game over for the tree.

  • WxDano
    11 years ago

    Surely the PW or Building Dept would like to know their inspector missed something that the landscaper didn't care to check on. Right? Wouldn't a public safety dept want to know this?

  • ken_adrian Adrian MI cold Z5
    11 years ago

    Ken, what about crushing pressure by the expansion of root system over the years?

    ==>> yes.. i ignored that comment.. because i cant conceptualize what you mean ...???

    the shear weight of the tree above ground is going to compact and crush that which is below it??? .. hmmm.. never thought of that.. i my world.. let me suggest you will be long dead and gone before that transplant gets to that point.. lol ...

    eahamel ... what i tried to say.. was that i dont know how the homeowners PVC system physically attached to the city pipe.. which i presume is NOT pvc ... but i still dont think that connection is the homeowners responsibility ... just pull a backhoe up to the curb.. and start trying to dig on the cities sewer.. i am sure someone will be in your face pretty fast ... but i do have some very vague THIS OLD HOUSE memory about them working on such .. but alas.. i dont know ..

    anyway.. typical suburban lot.. i dont care where you put a tree with hundred foot potential .. on that lot.. its roots will find a problem .. and on that logic.. you may as well not grow any large trees ...

    scot.. its simple.. do you want the tree or not ...

    if no .. get rid of it .. the sewer is not an issue ...

    if you can live with it.. and you will spend the rest of your life fixating on whether gravity and physics will ruin your pipe.. move it ... peace of mind has nothing really to do with this sewer discussion ... in my world.. if there is the potential for it to bug you ... GET RID OF IT ... lifes too short ... [its the same logic of the large carp tree overhanging your bedroom ... if you think its going to crush you in your sleep in the next storm.. what difference does it make.. how precious or rare it is.. its a psyche issue.. not a tree issue] ...

    if you can live with it.. dont want to waste it.. move it ... and relax your brain ...

    if you want the oak.. move it.. so you never have to worry about your pipe again.. simple as that ....[is there an echo in here???]

    ken

  • ken_adrian Adrian MI cold Z5
    11 years ago

    why wouldnt large trees eventually sink themselves.. if there was such a compaction point under the trunk ????

    they must distribute that weight thru the web of root structure ...

    it would be funny to see swamp trees.. slowly sinking to their canopy.. in the muck ... it just doenst happen.. does it???

    ken

  • brandon7 TN_zone7
    11 years ago

    Sinking is not how the tree roots could crush the pipe. Think of the tree roots as a giant python that could push or even squeeze the pipe. It's not likely to happen, IMO, but that doesn't mean it won't. Because of the possible future need for access and because of the possibility of damage (pushing, crushing, ripping the pipe up if the tree ever fell, etc), I wouldn't want a tree planted right over my sewer pipe.

  • ken_adrian Adrian MI cold Z5
    11 years ago

    i agree.. i wouldnt either ... its a metaphysical debate at this point ...

    wish it were a maple.. so i could just tell you to kill it.. lol

    ken

  • lou_spicewood_tx
    Original Author
    11 years ago

    Lol. Ken, I was planning on planting shantung maple in that area. Something more colorful than plain Live Oak that is widely planted everywhere. Boring... In fact, I may end up the only person not to have live oak trees in the front yard next year on my street. Every single house has Live oak... Say hello to oak wilt... I already have ancient Escarpment Live Oak grove in the backyard so I don't see the point for more Live Oak trees in the front yard anyway.

  • fmart322
    11 years ago

    I've been plumbing over 20 years now. Over this time I've never seen a root system penetrate a PVC drainage system. (Unless they forget to glue a fitting of course) find out if they used the heavy pvc pipe, schedule 40 over the thin green pipe.
    Here in my area we dig down 42" for utility work due to thaw heaving, ect.. I'm sure it's different in your area. The weight may factor into it some day.
    Now, with all that said, its not hard to go around large trees with plumbing. You just dont use hard turns like 90's, use 2 -45's to make a bend.
    With all that being said, if the tree is small enough to move now, do it just for peace of mind. I doubt the tree will harm your system as long as the plumbing was done correctly with the heavy grade schedule 40 pvc.