Water Feature on Top of Sanitary Drainage Pipe

[markullrich]

Hi everyone, I need some advice on whether I can place a basin and rock feature in a location with a sewer pipe underneath. Here's a photo: https://www.dropbox.com/s/5ug09c2qwn1362a/Screen Shot 2023-05-18 at 5.36.08 PM.png?dl=0

The two primary concerns are:

1) Weight. The rock feature will be largely supported by the vertical PVC in the middle which will sit in the basin under the grated platform. The rock feature is 1000 lbs. Luckily the drainage pipe is off-center and not directly under. And the weight of the basin and water is roughly the same as the soil was before removing it. But still concerns about the weight around this pipe.

2) Freezing. Sewer pipes have to sit below the frost line to be up to code (mine is about 20 inches), and with the basin on top this leaves it with only a couple inches of soil between the basin. I can certainly heat the water in the pond but it does pose some additional risk. Not sure if the 50" of exposure is enough to worry about or not.

Thoughts from the community?

Many thanks!
Mark

 

[Beercan31]

As far as the exposed sewer pipe bearing weight you can bridge the pipe with a slab of slate of from any box store at least 2" thick to transfer weight away from the pipe.

What climate zone are you in?
moving water is less likely to freeze but that lower temperature of water can transfer to the sewer pipe and cause trouble.

 

[GBBUDD]

6 inches of sand over the pipe . Or a steel plate,/ u channel / flat stock . Will all do the trick to help protect the pipe from Weight.
However if your pond gets drained you now have an issue of freezing temps. Can the line pipe be routed out along the edges of the feature so if it fails everything won't need to be destroyed

 

[j.w]

@markullrich

 

[markullrich]

As far as the exposed sewer pipe bearing weight you can bridge the pipe with a slab of slate of from any box store at least 2" thick to transfer weight away from the pipe.

What climate zone are you in?
moving water is less likely to freeze but that lower temperature of water can transfer to the sewer pipe and cause trouble.

Thanks for your reply and recommendations. I'm in the high desert of central Oregon, so we have real winters here. I'm hoping to have a septic pro take a look and advise on whether it should be rerouted or not. I do think building a shelf on either side of the pipe should easily protect it from the weight of the basin.

 

[markullrich]

6 inches of sand over the pipe . Or a steel plate,/ u channel / flat stock . Will all do the trick to help protect the pipe from Weight.
However if your pond gets drained you now have an issue of freezing temps. Can the line pipe be routed out along the edges of the feature so if it fails everything won't need to be destroyed

Thanks for your input. I do think a shelf of some kind around the pipe should protect it. *Might be able to reroute it, but there's a large boulder to it's left to contend with - might need a small excavator. I'm going to have a septic pro take a look.