Does anyone know what materials are acceptable for potable water pipes? We have a small job for a water plant and were going to use carbon steel pipe. I've read on another forum that it is ok but coating or galvanizing is necessary.
I know copper, PVC, ductile iron, cement lined are ok. Hate to buy 20' of 4" copper when we only need 4 feet. I would think 304L and higher is ok but read mixed views on it. It's good enough for food and dairy if installed properly.
Ultimately it comes down to local codes and the governing code which I think is AWWA and I do not have it.
Any imput on the matter is appreciated.
Is there a restriction for the pvc? Outside of that, for metals copper would be your best choice, 316L I believe would be your better choice in 300 series, unless there is specific chemistry run on the system I don't think 304L would be a good idea. There are plenty of old iron water lines out there, I would say it to is a viable alternate.
Two cents worth,
Gerald
No restriction on the pvc. This plant is brutal on pvc even with flex connectors so we prefer metal. Copper is best but it was priced using CS before I was involved. We're building a header. The PH levels will be correct since it is already treated water so no concerns there.
The pipe systems we usually work on are flushed per specs and treated with chemicals to inhibit corrosion. Different industry. I've demo'd old CH/HW lines and seen some in great shape and seen some with nearly an inch of growth on the I D walls.
Thanks for the reply.
By G.S.Crisi 
Date 07-27-2007 17:50
Edited 07-27-2007 17:52
From material suitability (corrosion resistance and prevent water contamination) standpoint, all of the mentioned materials are OK.
However:
copper and stainless steel are too expensive
PVC is fragile, i.e. it cracks very easily
ductile iron and cement pipe are recommended for long pipelines, especially underground, not short runs
So, the best choice is definetely galvanized carbon steel. It doesn't need to be seamless. Many years ago, there was an ASTM standard covering this pipe, which was ASTM A-20. This standard, however, has been discontinued and replaced by A-53, galvanized.
Giovanni S. Crisi
Sao Paulo - Brazil
Please let me interject. Our homestead in Chugiak, Alaska was built by my grandad in 1951. The pipes were all steel, and are still in place today. Excellent water, no bad elements.
Don't know the codes but hey, proof positive...........oh, and the house was built with railroad ties and stucco..........
My great grandad and My grampop put a galvanised steel waterline in that fed spring water by gravity from the spring on the hill to a camp great grampop built and to thier homes. This was 1 1/4" pipe put in in the '30s. It was rusted darn near shut by 1962. The hilside around that spring is and always was a hardwood forest, lots of oak, especially since the blight killed all the chesnut. That water is highly acedic, eats through copper pipes in a decade or two. The new line was plastic.
Carbon steel it is. Thanks guys.
