levelling pitch on sewer line

[creepyoldguy]

I've got a long run of 4" line that has been installed and awaiting burial for awhile. upon checking it with a level I noticed that the pitch is all over the place. There is precious little fall to work with on this particular project, so it all has to be uniform.

Now I have this problem that whenever I make adjustments on to the pitch it screws up my previous adjustments from down the line. I found myself putting heavy stones on the pipes to weigh them down in some spots. It also seems like I'm spending way too much time and effort on hands and knees, digging and then coming back and re-digging- over and over again. There should be a way to hold the pipe still after it's set how I want it. It feels like I'm not making any progress.

Suggestions?

Thanks,
S

 

[SewerRatz]

The pipe should be laid on a bed of stone. The stone should be set to the proper pitch. Then you should put stone over the top by 12 inches. Here is a good pdf chat to look at.

http://www.wjordan.com/files/SS02PipeTrench1.pdf

 

[Sponsor]

 

[Leejosepho]

I've got a long run of 4" line that has been installed and awaiting burial for awhile. upon checking it with a level I noticed that the pitch is all over the place. There is precious little fall to work with on this particular project, so it all has to be uniform ...

I had a similar situation last fall with only 3-1/2" of drop available for a 35' run between tanks, and I used a string stretched from one end to the other while doing whatever it took to get it straight.

 

[creepyoldguy]

existing pipe

I see how this works the best if you are putting in a new pipe, but this pipe is already in. Is there a good strategy for digging underneath a pipe that is already there? Is there some kind of tool?

 

[Leejosepho]

Here are a couple of my favorites:

 

[NHmaster]

Run a level string over the center line of the pipe and measure from the string to the top of the pipe. Minimum pitch for 4" is 1/8 ipf. Drainage pipe should be bedded in clean gravel or sand with no large rocks or stones either under or over the pipe. Once the pipe has been properly pitched it can be secured against movement using two pieces of re-bar approximatly 3' long, driven at a 45 degree angle on either side of the pipe and finally bound at the top (over the pipe) using mechanics wire. these supports should be place every 6' maximum and at all branch locations and changes of direction. A transit can be used in lieu of the string if you have access to one. If you are going to do it do it right, do it once. It's expensive and aggravating to have to dig it up again in the future.