Connecting pipes of different material
Connecting pipes of different material
(OP)
I have a 24" line that I am running under a creek. under the creek, i am required to use DI. I want to tie in to a 24" line that is 949_PVC on the other side of the creekbed.
TCEQ (Texas Commission on Environmental Quality) madates that a manhole be used when changing direction or moving laterally...but doesnt say you must use one if changing materials. I am wondering if I need to put a manhole there, or can i just put a fitting there to make it work and be ok?
TIA, Chris
TCEQ (Texas Commission on Environmental Quality) madates that a manhole be used when changing direction or moving laterally...but doesnt say you must use one if changing materials. I am wondering if I need to put a manhole there, or can i just put a fitting there to make it work and be ok?
TIA, Chris





RE: Connecting pipes of different material
However, for a sewerline crossing a creek, I would suggest manhole on both sides.
RE: Connecting pipes of different material
RE: Connecting pipes of different material
If it is a pressuized main, then a manhole would be out of the question (assuming of course that you are using the manhole to compensate for different pipe ODs).
If the PVC OD is equivalent to the ductile iron pipe OD (I apologize for my ignorance, I've never seen the designation 949 PVC or I might be of more help). Then a ductile iron mechanical joint sleeve (or any ductile iron fitting) used in combination with MJ restraining systems (such as EBAA Iron Megalugs or Sigma One-Loks) are often used, but be aware that different models of retainer glands are use for the PVC and ductile iron pipes.
If the PVC OD is not-equivalent to the ductile iron OD, then a transition sleeve may be required to transition the ODs, these sleeves are available through most manufaturers such as EBAA Iron, Smith-Blair, Dress, Romac, etc.
There are other options, but those are the ones that I see most commonly.
And please, please check local codes and specifications for your area, as they often have requirements for these types of transitions.
RE: Connecting pipes of different material
tnboy, i apologize for my own ignorance...the 949 PVC pipe may not be a real designation, that is just what the plans had written on them.
New problem with this though is that the surveyors we hired said the creek we were crossing was only 6 ft deep and it turned out to be about 15.... now the flowline of the pipe pretty much matches the creek flowline. The bottom of the DI pipe is only about 2 inches off the creekbed. I have been looking for a full day now in EPA and contract documents to see what I am allowed to do and have no idea...
any ideas?
RE: Connecting pipes of different material
RE: Connecting pipes of different material
A sleeve would also still be a viable option (and I would think a more cost effective option, the price of excavating placing and grouting a manhole versus installing a sleeve). Whether it is a transition sleeve (for differing ODs) or a standard mj sleeve (for matching ODs).
Back to the PVC notation, I know much more about ductile iron pipe than pvc pipe, but I do know that C900 & C905 PVC ODs do match the ODs for ductile iron (and often ductile iron MJ fittings are used to with this PVC pipe).
RE: Connecting pipes of different material
I am spec'ing to reinforce the embankments, and then encase the DI pipe in another steel pipe because there will be a joint exposed (code spec'd)....it is going to raise the water level about 2.5 feet right there, so I then plan to cover this in gravel, letting the natural flow cover it in silt and keep from creating a giant erosion hole on the downstream side of the pipe
sound like a winner?..anything i am missing?
"Don't worry about the world coming to an end today. It's already tomorrow in Australia."
---Charles Schulz
"Beer is living proof that God loves us and wants us to be happy."
---Benjamin Franklin
RE: Connecting pipes of different material
RE: Connecting pipes of different material
RE: Connecting pipes of different material
RE: Connecting pipes of different material
what are some good ideas for enbankment support, i was thinking something along the lines of a concrete winged structure around the pipe....
"Don't worry about the world coming to an end today. It's already tomorrow in Australia."
---Charles Schulz
"Beer is living proof that God loves us and wants us to be happy."
---Benjamin Franklin