Furniss
Well-known member
Over here soakaway trenches are allowed 1% maximum fall, and more often than not we are working to minimum fall (2%) on at least one of the connections of foul from the house to the tank/treatment plant etc in order to keep the system as shallow as poss to either meet requirements for maximum backfill round system or to have sufficient falls going onwards from tanks to drainage beds etc and still arrive at or above our maximum invert depth allowed on soakaways or drainage beds.what are you guys doing that requires that level of machine control?
Foundations and septic tanks? Driveways?
Most our drawings unless highway etc don’t have levels other than what suits the site
How do these systems go on on steep
Hills doing new road say 300mm dig where ground is up and down and very steep down hill as well?
It's all checked with laser by the authorities before its signed off and backfill.
We usually dig say 3cm below grade (depending on the going) on each pipe run to allow a pipe an even bed and have a perfectly flat plane to lay pipes, if your working to 2% you can’t really afford to go up n down in the run.
Its pretty precise work and each cm matters.