Tree roots in the drain pipe

Discussions of Urban Forests and trees in general, including their growth, care, and impact on society. Discussions of specific trees, parks or forests in urban areas should be included in the proper forum of the Trip Reports and Site Descriptin category of this BBS.

Moderators: edfrank, dbhguru

User avatar
PAwildernessadvocate
Posts: 389
Joined: Sat Mar 13, 2010 3:31 pm

Tree roots in the drain pipe

Post by PAwildernessadvocate » Thu Mar 07, 2013 11:51 am

Well, I knew more than ten years ago when I moved in and started planting trees and shrubs in my side yard that this day may eventually come.

The main drain line from the house to the street had been draining extremely slowly in recent weeks, with sewage backing up into the basement when a large amount of water is used, such as when doing a load of laundry. Today I had the line snaked and sure enough it was tree roots. Might have been the hemlock I planted in November of 2001, or the London plane tree I planted in May of 2002, both of which are quite large at this point, much taller than the house. Or it could be the smaller blackgum I planted not long after that. All three of these trees are in close proximity to the drain line. Or maybe it could even be the big Norway maple or black cherry which are further away but have both probably been growing for at least 40 years.

In any event, the line is clear now but will need to be snaked periodically. Naturally, now that the roots have found their way into the line they will of course keep growing back. Any ideas for a permanent solution short of cutting down all my beloved trees? I seem to recall seeing a method on This Old House once where a sleeve is inserted into the line and then inflated. Then, a liquid substance is pumped into the line between the sleeve and the original line. Once the substance hardens, the sleeve is deflated and removed leaving you with a permanent hardened contiguous pipeline lining the interior of the old line, supposedly impenetrable to tree roots. Anyone else heard of this? I bet it's expensive.
"There is no better way to save biodiversity than by preserving habitat, and no better habitat, species for species, than wilderness." --Edward O. Wilson

User avatar
Rand
Posts: 1217
Joined: Tue Mar 16, 2010 9:25 pm

Re: Tree roots in the drain pipe

Post by Rand » Thu Mar 07, 2013 12:57 pm

My dad used to throw a handful of copper sulfate down the drain tile around our house once a year. Seemed to keep the cottonwood tree roots out. Don't know how legal/environmentally friendly this might be, but it was out in the country.

User avatar
PAwildernessadvocate
Posts: 389
Joined: Sat Mar 13, 2010 3:31 pm

Re: Tree roots in the drain pipe

Post by PAwildernessadvocate » Thu Mar 07, 2013 4:52 pm

Thanks for the suggestion, I will look into that possibility.
"There is no better way to save biodiversity than by preserving habitat, and no better habitat, species for species, than wilderness." --Edward O. Wilson

User avatar
Will Blozan
Posts: 1153
Joined: Fri Mar 12, 2010 7:13 pm

Re: Tree roots in the drain pipe

Post by Will Blozan » Thu Mar 07, 2013 5:11 pm

I had the same problem here in NC... I was able to replace the line with PVC and have not had a problem since. I had the old crappy terracotta pipes. If you can replace it without severe damage to the trees or your wallet that is how I would approach it.

Will

User avatar
PAwildernessadvocate
Posts: 389
Joined: Sat Mar 13, 2010 3:31 pm

Re: Tree roots in the drain pipe

Post by PAwildernessadvocate » Thu Mar 07, 2013 5:40 pm

Yeah I am worried about having someone come in and cavalierly dig up the line with a backhoe without regard to damaging the trees. They are quite close to the line. Maybe the thing to do would be to dig up the line myself with hand tools, because I trust myself to be as careful as possible around the roots, and then have professionals come in to replace the line with PVC. That would probably also save me some money if I did that much of the work myself. Maybe the old line could even simply be left as it lay in the ground and put the new one on top of it or next to it.

How long has your PVC line been in the ground now?
"There is no better way to save biodiversity than by preserving habitat, and no better habitat, species for species, than wilderness." --Edward O. Wilson

User avatar
Will Blozan
Posts: 1153
Joined: Fri Mar 12, 2010 7:13 pm

Re: Tree roots in the drain pipe

Post by Will Blozan » Thu Mar 07, 2013 6:20 pm

Mine has been in about 12 years. I think it is PVC but it may be ABS- check local codes first!

How close are the lines to the trunk and how much of the root zone (%) would be severed? Most trees can handle a good bit of loss but it is the anchor roots that are a concern as well. My line was about 10 feet from a 30" white oak and about 2 feet from a 12" hemlock. Both are alive and healthy even though some 4" diameter roots were severed. I would estimate, with the assumption of the root zone being consistently and evenly distributed around the trunk (which is likely not the case) that the hemlock lost 40% of its root zone and the white oak less than 30%.

Will

User avatar
mdvaden
Posts: 883
Joined: Tue Sep 07, 2010 6:30 pm

Re: Tree roots in the drain pipe

Post by mdvaden » Thu Mar 07, 2013 7:33 pm

About 2 years ago, I replaced a lawn and French drain, that another landscaper installed for a couple merely one year earlier.

In just a year, the pine and deodar cedar roots, passed through the fabric they lined the trench with, through the river drain rock, through the fabric on the pipe, and crossed the diameter of the 3" perforated pipe.

Difference with my work .... I added a barrier material on the tree side. I vary it from tree root barrier, to bamboo barrier, to pond liner. Remarkably, pond liner works pretty good for most tree roots if I have extra scrap left over in long enough lengths.

...
Attachments
roots_600.jpg
M. D. Vaden of Oregon = http://www.mdvaden.com

200 Pages - Coast Redwoods - http://www.mdvaden.com/grove_of_titans.shtml

Portraits & Weddings - http://www.vadenphotography.com

Porter
Posts: 11
Joined: Fri Oct 26, 2012 2:19 pm

Re: Tree roots in the drain pipe

Post by Porter » Fri Mar 08, 2013 7:57 am

I remember seeing that same This Old House episode with the sleeve method for fixing a sewer line. Really cool but I had the same thought that it's probably really expensive. It does target the main problem which is usually a crack or weak joint in the pipe. No matter what you do roots will most likely continue to grow in the line if the crack/weak joint isn't fixed. Systemic herbicide treatments can work well to take care of the immediate root(s)causing the problem in and outside of the pipe. This treatment is usually coupled with an auger or some other cutting tool to clear the pipe. I believe copper sulfate isn't permitted in all states so make sure to check before using it.

Here's a link to some additional info: http://pested.osu.edu/documents/CommStu ... ontrol.pdf
Tim Porter

User avatar
AndrewJoslin
Posts: 408
Joined: Sun Mar 14, 2010 7:36 pm

Re: Tree roots in the drain pipe

Post by AndrewJoslin » Fri Mar 08, 2013 8:39 pm

Mario's post about roots penetrating a perforated french drain pipe points to what I think is a huge misconception about tree roots and lateral lines (house sewage lines). Tree roots do not penetrate lateral lines that are not already leaking. As Will mentioned, the typical material used for these is fired terracotta or clay. Over long periods of time fired clay pipes form cracks, from simply sitting in moist ground and from ground shifting and other causes (heavy equipment rolling above them etc.) Once cracks form and water seeps, fine tree roots grow to the water and nutrient source and eventually obstruct the pipe. The result is the same as if the tree did break the pipe but I think it's important to blame the already cracked pipe material not the tree.

If you think about it... trees do not have some extra sensory perception that says "Aha! There's water and good nutrient inside this perfectly sound pipe! I think I'll bust the pipe so it's easier to get my roots in there!". But once water starts seeping through cracks all bets are off. That's why Will's PVC line has been holding up so well, it doesn't crack as easily as a clay pipe and invite the roots in.
-AJ

User avatar
PAwildernessadvocate
Posts: 389
Joined: Sat Mar 13, 2010 3:31 pm

Re: Tree roots in the drain pipe

Post by PAwildernessadvocate » Sun Feb 12, 2017 4:44 pm

Happened again. Snaked the drain this morning and sure enough it was tree roots. No surprise. The hardware store where I rented the drain snake sells copper sulfate (Roebic brand), and they recommended that I use it. So it must be legal in Pennsylvania. I don't want to use it though if there is a risk of killing or damaging the tree(s) to which the roots belong. The label says "this product works without harming surrounding trees," but what about the tree itself with the roots in the drain? The other option is just rent the drain snake every four or five years, whenever the line backs up again.
treeroots1.jpg
"There is no better way to save biodiversity than by preserving habitat, and no better habitat, species for species, than wilderness." --Edward O. Wilson

Post Reply

Return to “Urban Forests, Trees, and Landscapes”