maximum sewer fall

[phild01]

I am trying to work out best way to connect to sewer from my elevated site. The site is steep and I think the sewer service to the new bathroom will be limited by any permitted maximum fall. I can't do a vertical drop and asking if in fact there is a maximum permitted fall for the sewer service line to the Main sewer connection point several metres lower?

[Belair_Boy]

G'day phild01

I asked the same question when installing the sewer run from my house build to the road and as far as I could find out, there is no maximum fall (only a minimum).

I have about 65m of run at a fall of 3.5 : 1 as it follows the steep section of driveway.
The potential problem as far as I can see is the water leaving the solids behind but the next "wave" should take care of it.
The option of having vertical drops with sections of lesser fall between would require much more rock to be dug out and many more joints for potential problems to occur. This and the fact that the waste has to change direction so often made the steep straight run look like the best option.

If you put enough IP's in then you should be able to deal with any future issues.

It may be possible to speak to the plumbing inspector in your area and see what they say but it is just as likely to open up a can of worms and create more problems for you.
If your plumber is happy to do it then go for a steep run, he issues the COC after all. :)
Good luck.

[plum]

I'm not up to date with the regs, but after a certain grade the pipe must be anchored with poured concrete blocks every so often to secure the pipe.

[wonderplumb]

There is only a minimum fall for sewer. As plum suggested it will have to be sparged and supported at any change in direction, depending on the fill.

[phild01]

Thanks for the info, very helpful. My situation is a granny flat. The Boards sewer main is on my property and long ago I had a junction inserted to it for the house (and too high for new bathroom below exist. house level). I did not use the pit at lower ground level that was originally provided for me. Now it might be convenient to use this as well but that would mean my property will be using 2 connection points to the Main. Not sure about this and wonder if I can be charged extra rates for this or any other issue?

[manofaus]

ring the council. I was told they would wave the extra fee and would be noted on documentation at the council.