determining minimum slope in pipe not flowing full 2

[greekmom]

I have one house that I am hooking up to a sanitary sewer main 200 feet away via an 8" HDPE pipe, therefore pipe not flowing full. How do I calculate what pipe slope is necessary to flow successfully?

 

[LHA]

You are going to have to solve for slope at full flow, then determine partial flow velocity to be 2.5 fps or more, using the relationships and equations on pages 111-113 here:

http://164.156.71.80/VWRQ.asp?docid...aspx?fs=0442d740780d00008000084d0000084d&ft=1

Remember: The Chinese ideogram for “crisis” is comprised of the characters for “danger” and “opportunity.”
-Steve

 

[rcooper]

1:50 is a good starting place.

 

[gsroy2]

You use the old standby meathod.....ITERATION!!

 

[dicksewerrat]

Are you using an 8" pipe for the service? unless you have a 5 bathroom house that is way over sized. cut back to a max of 6" and even check out a 4". the slope will be the diff. in elev. from the house outlet and the elevation of the main where you hook up divided by the 200 feet to the main. Has nothing to do with half full or full

 

[Maury]

The standard in my area is 6" Dia. pipe at a slope of 1/8" per foot (these are minimums for size and slope). This provides a flow capacity of 1.2 cfs and a velocity of 3.5 fps, flowing full, calculated with Manning's equation.

 

[hartz]

For an ambitious analytical method of doing this, you could probably refer to this manual.

http://www.concrete-pipe.org/manual/CHAPTERS/CH 1.pdf

maybe too much effort for simple task though
-hartz