How do you do this? I assume a sand base in the bottom of the trench would be a good start and then just work with it until you get it right? I was wondering if I determined where the bubble on my level was at that slope, could I use that as a guide?

Brad

With a 4 ft level you could use a 1 inch (or 3/4 inch) gauge block put the gauge block on the low end and read level. Just push and pack dirt under the pipe to get the right elevation.

Usually this is done with a surveyor's type level, if the pipeline is at all long. The drop would be 2.5" every 10', so probably the guys would check it each 10 or 20 feet. Sand pushed under the line at each station will be used to temporarily set the slope, and once it's established, the rest of the sand would be backfilled under and then backfilling completed.

You can make a water level for this purpose. A lenght of garden hose, water filled, with clear tubing at each end. The water in the clear tubing will always be level from one end to the other.... Allowing you to have a stable reference... Can be a bit tricky, but it's a good accurate way.

A laser level and a measuring stick could do the job. You can rent'em if you don't wanna buy.

A short one could be done by setting a plank level (with carpenter's level) adjacent the pipe, and using that as a reference...

How long's the run?

J

About 12 years ago I installed a 3 inch PVC line (about 50 ft). I was REALLY tight on the fall from the start to the septic tank. I had one 20ft section with a drop of less than an inch from one end to the other! That line has NEVER clogged and is still in use. (A one bedroom, one bath apt with a kitchen).

Many of my levels have common slopes (1/8", 1/4", 1/2") designated right on the bubbles. Easiest way is to pick up a plumber's level for less than $10 at a hardware/home center.

No idea what your specific need is, but usually if you're "close" (+/- 1/16" from desired) drain lines will be fine. Just DON'T have any low spots where water can puddle.

What are you installing?

Quote:

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easy except that I'll probably be breaking out limestone for the whole thing!

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If your pipe will be laying directly on limestone or similar, you should add a bedding layer of sand or pea gravel, 3 to 4" thick, at a minimum.

Curious... Why so thick Spack?

You want 2" min under the pipe and typiclly, you'll have a 1" to 2" variation in the bottom of the pipe trench, especially with limestone, shale, rock etc.

3" to 4" bedding will help eliminate any "hard spots" between the pipe and actual bottom of the trench.

Not knowing the application - it may be over-kill, but site unseen, it's good practice.