Deep sewer lines

Looking at a park that has park owned sewer lines that are 15 feet deep that lead to the city sewer on the street.  There are 5 sewer lines that are all 15 feet deep leading to the city sewer line.  There was a break and it took a back hoe and many people to fix the broken sewer line.  Are there any issues with sewer lines being this deep?  Is that a deal killer?  Why would they be so deep and is that common?  Lines are 6" schedule 40 PVC.Thank you,Pat

Septic lines require a specific slope to work properly. Too much and the water runs away leaving the solids behind, too little and the fluids do not have the momentum to carry the solids.The depth is determined by the required drop to connect with the city and maintain the proper slope. Depth should not be an issue for the park.

I’m not expert like Greg but that would concern me. But then again, it would depend on the park numbers.I’m able to rent a small tractor with a backhoe to deal with a few feet of digging but I’d need to bring in a professional excavator operator for a 15 foot dig. I’m able to save a fortune by doing it myself as it requires  no permits when the owner is doing the work. You can handle most problems with a shovel if the lines are not very deep.

Thank you for the response.  How often do sewer lines break.  I know it depends on the soil, but is it a common occurrence and is it mainly due to soil shifting?Pat

This would not be a deal-killer for us.  Nothing like it.  Most sewer lines are park-owned.  And yours are sewer lines going to the city sewer, not a septic field, if I understand correctly.  So provided the rest of the park makes sense, then by all means, … buy it!You might talk to the plumber/excavator that did the backhoe work to understand what the problem was.  You might also run a sewer camera down there to verify the rest of the lines are in good shape (e.g. are not orangeburg or crumbling clay tile).  But deep sewer lines running to a city sewer main are definitely not 'deal killers.'Good luck,-jl-

Jefferson is correct, the depth of the lines is not nearly as important as other factors, like what they’re made of.  Also important is that they are properly bedded on compacted sand, that they travel in a single plane, and that the slope is about 1/4 inch per foot, or 2 percent.  The proper slope keeps solid material including grit, like sand and small gravel, moving while eliminating places where the effluent might stay too long.  Running a camera is always a good idea, get a film of it for the money you’re paying.   BTW, there is at least 1 utility dept in south OC that says they have sewer lines at 60 feet.Please note that if you’re doing the work yourself even shallow trenches in unstable soil can be deathtraps.  People have perished in trenches as shallow as 4 feet because they were working alone in unstable soil.  Jim Allen

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