DIP vs. HDPE?
DIP vs. HDPE?
(OP)
I work in the Rocky Mountains in Colorado. Every water district in my area requires the use of DIP for all water mains (generally 8" in size or larger). They will also allow the use of C900 for water mains. I have been asked by a client to propose the use of HDPE for the replacement of an existing 3" pvc plastic pipe. I know the District's first reaction will be "absolutely not!" These District's are not the most open-minded, mostly because I live in a small community and we do not have the most technically advanced people currently working for these Districts.
I guess my first question is: can anyone tell me why the use of DIP would be so important, especially when compared with HDPE? Please consider the following: I work in very cold conditions, lots of freeze/thaw, also bury these mains at least 8' deep, and the soil types can be very rocky.
I know the use of HDPE pipe is becoming more and more common for water mains, but I also believe it is fairly new in this type of use, so truly understanding it's life span seems to be an issue. From the little research I've done, it seems that the most important part of construction that ensures a longer life-span is correctly welding the joints together. Besides that, the installation seems fairly straight-forward.
Being the local PE that steps up the plate and attempts to educate the local municipalities to change their ways, is a long-standing challenge that I would prefer to not take. BUT, if I did, does anyone have a good reference source to start with?
Any advice or opinions would be appreciated.
I guess my first question is: can anyone tell me why the use of DIP would be so important, especially when compared with HDPE? Please consider the following: I work in very cold conditions, lots of freeze/thaw, also bury these mains at least 8' deep, and the soil types can be very rocky.
I know the use of HDPE pipe is becoming more and more common for water mains, but I also believe it is fairly new in this type of use, so truly understanding it's life span seems to be an issue. From the little research I've done, it seems that the most important part of construction that ensures a longer life-span is correctly welding the joints together. Besides that, the installation seems fairly straight-forward.
Being the local PE that steps up the plate and attempts to educate the local municipalities to change their ways, is a long-standing challenge that I would prefer to not take. BUT, if I did, does anyone have a good reference source to start with?
Any advice or opinions would be appreciated.





RE: DIP vs. HDPE?
RE: DIP vs. HDPE?
Check out this website for some good information on all PE pipes though it probably doesn't have exactly what you are looking for. The Handbook is pretty valuable though:
http://www.plasticpipe.org/index01.php
I believe you can getPC350 DIP down to 3" though.
RE: DIP vs. HDPE?
RE: DIP vs. HDPE?
http://www.dipra.org/pdf/DIPvsHDPE.pdf
somebody please post something comparable for HDPE if available. I can provide the following site which has some useful information:
http://www.kwhpipe.ca/know_artwhite.asp
RE: DIP vs. HDPE?
The problem that comes up is you can have a set of specs requiring a contractor to use something he's never used before, but lay the blame for any problems with the material on him. The pipe-contraction issue mentioned above is one example- that could have been some expensive knowledge to pick up.
In general, sales literature as mentioned above is useful, even if one-sided. If every utility around there uses DI, they probably know all the disadvantages of it. And if there aren't any, there wouldn't be much reason to switch other than installed cost.
RE: DIP vs. HDPE?
And while the stuff in the system may not be the same quality at the product sold today, it is hard for systems to regain the trust in an product that should last 100 years or so when they have seen failures in 10 years.
At two years even the best spec's warrantee wear out.
Hydrae 2ยข