Slow bends in drainage

[MIStructE_IRE]

Hi,

We’ve often used slow bends (15 degree) in underground drainage for surface water because it seems reasonable.. Is there a basis of design for slow bends or some guidance/reference as to what is acceptable?

I’ve never done this for wastewater though.

Thanks

 

[bimr]

Don't believe so. The problem with bends is that it makes the drainage pipe difficult to clean. Cables are used to pull a cleaning head through the pipe and the cable will bind on the sidewall and destroy the pipe.

 

[cvg]

bends are not recommended (slow, long radius, or otherwise) for either surface water or sewer. If you want to put in an angle point in the pipe, than use a cleanout or manhole. not only is it difficult to clean, but more likely to clog with any sort of bend