How to fix stormwater pipe too close to surface?

[ArashM]

Hi all,

I've got a stormwater pipe going perpendicular to my land at the end of the block and connecting to stormwater drain in the left corner of the land. 

I was digging to put in an ag pipe and after digging a bare 10cm I hit this giant pipe on the right side of block.

On the right side pipe is burried only 10cm deep while on the left side where it connects to the drain it's over a metre deep. 

I don't understand what these geniuses were thinking putting in the pipe so close the surface. 

I'm gonna plant privacy plants at the back fence (most likely golden palm tree) and now I'm worried if the roots would be an issue for this pipe 😞

 

 

 

 

Any thoughts?

Just some additional info, the pipe seems to be wrapped with fabric and gravel (see photo below) which i am now ripping apart as I need to dig the clay soil out and replace with top soil. I also need ti dig under the pipe so I can pass my ag pipe next to the end retaining wall. Although I suspect there's an ag pipe already running along this pipe to the stormwater drain since I can see the exit to the drain.

 

 

[JacobZ]

Hi @ArashM,

It's certainly not an ideal location for the pipe, but I believe 100mm to the top of the stormwater pipe is in line with the Australian and New Zealand Standards. It might be worth contacting your local council's water authority to ask some question as rules may be different in your area. It is certainly possible to bury them deeper, but it looks like it is up to code. These types of stormwater pits are also often council assets, so any modifications would likely need to go through them anyway.

Roots can certainly cause problems with pipes, so planting privacy plants directly over them is not ideal. As their roots will seek out water, they can potentially find their way into the pipe causing blockages and damage to the pipe.

You could install a root barrier such as this Jack 600mm x 5m Garden Root Barrier around the pipe as an extra layer of protection, but you might still have trouble in the future.

Unfortunately, I think the best solution is to avoid planting in this area.

You could install some fence extensions to add privacy on that side of the property. A physical structure like a pergola or shade sail could also be a good option.

Allow me to tag @Nailbag, @prettyliving and @michael1972 to see if they have any ideas.

Let me know what you think.

Jacob

[Nailbag]

Hi @ArashM 

Looking at your fence line, it sits upon a retaining wall. This means that in some earlier stage that pipe was further under the original ground prior to your land being excavated. Though not a satisfactory answer to help your situation it would explain the shallow depth.

As the length of the fence line appears to be an easement, I would have to agree with @JacobZ in avoiding planting in this area as it would contravene local guidelines. Any issue arising from the tree roots would be at your cost.

But you could still plant further in front clearing the easement and utilising the root barrier Jason suggested.

Nailbag

[ArashM]

Yes, it appears that the 1.5 m depth from the back is an easement. I originally wanted to create a raised garden bed to plant privacy plants so their root would not reach the stormwater pipe but it appears that is now also not an option, unless I build the blocks outside of the 1.5m easement and raise the easement with top soil. Would I then be able to plant noninvasive privacy plants.

 

[EricL]

Hello @ArashM 

I'm afraid any plant that is placed along that area will cause plant root problems which in turn will lead to plumbing problems. I'll have to go with my friend's suggestions and that is either to extend your fence or install a shade sail for more privacy.

If you have any other questions we can help with, please let us know.

Eric

[ArashM]

What if i create a raised bed 50-60 cm and covered the bottom with root barrier. It'll let water through while keeping roots away from sub soil. This should work, shouldn't it?

[JacobZ]

Hi @ArashM,

I imagine it would work for some time, but the size of the plants needed to create privacy on this side of the property would likely have roots that extend deep into the ground.

It is likely that over time; these roots will eventually break through the root barrier and find their way to the stormwater pipe. Adding a garden bed on top of the pipe will make it more difficult to get to the pipe in the eventuality that damage occurs.

You could certainly give it a try, but I can't confidently say you'll have no issues in the future.

Allow me to tag @mich1972 and @Noelle to see if they have any advice.

Let me know if you have any further questions.

Jacob

[Noelle]

Hi @ArashM 

It would be most unwise to plant privacy trees above or close to a storm water drain as it is almost inevitable that the roots will, at some stage, damage the pipes - and the expense to fix it will be all yours, as will be the cost to remove the trees!

Root barrier materials are not designed to be placed under trees, but rather vertically to prevent roots from growing sideways into easements, under foundations, into neighboring properties etc. Used under trees will certainly affect their overall health and vigor as well as their stability.

I have to agree with most of the other contributors to this conversation - planting within an easement is not a good idea at all!

[ArashM]

I understand, so to clarify, I can still put plants over the easement but nothing that grows tall such as privacy plants. Any other decorative plants should be fine, correct?

Thanks 

[JacobZ]

Hi @ArashM,

Anything with roots will likely cause issues if they are directly over the stormwater pipe.

There are plants with shallow root systems that you could try, but they will not grow tall enough to give you any privacy and there's no guarantee they won't find a way into the pipe. 

My suggestion, as mentioned above, is to use structures such as shade sails or timber screens for privacy and to plant your plants elsewhere in your yard. Alternatively, you could speak with your local council about having the pipe rerouted, but the cost for this would likely exceed the benefit.

Let me know if you have any further questions.

Jacob