Copper Pipe as Water Main
Copper Pipe as Water Main
(OP)
Hi All,
I have a question that I'd like to get some feed back on.
I've looked through codes/standards of various municipalities regarding the type of materials that can be used for water main lines. They all share the typical ones:
1. Ductile Iron
2. Concrete
3. PVC
However, none of them list copper as an acceptable material to use for a water main. I am aware of the cost difference, but is that the only reason? Does copper behave poorly underground? If so, then why do they use specify copper for service connections? What would be a good source for such information?
Thanks in advance!
I have a question that I'd like to get some feed back on.
I've looked through codes/standards of various municipalities regarding the type of materials that can be used for water main lines. They all share the typical ones:
1. Ductile Iron
2. Concrete
3. PVC
However, none of them list copper as an acceptable material to use for a water main. I am aware of the cost difference, but is that the only reason? Does copper behave poorly underground? If so, then why do they use specify copper for service connections? What would be a good source for such information?
Thanks in advance!





RE: Copper Pipe as Water Main
The parameters of the service installation such as pipe velocity and diameter are somewhat defined making copper more acceptable. The ease and speed of installation is probably the biggest factor for services.
RE: Copper Pipe as Water Main
In addition to remarks from bimr:
If you go back 50 years and more, both copper and certain brass qualities were used commonly for water, hotwater and steam pipelines, both for processes and especially for high- quality shipbuilding pipelines and accessories. The materials where not much used for diameters above 1 - 2 inch.
The reason for use was mostly corrosive resistance over time. Price compared to other competitive materials was not that large (I believe), where and if alternatives actually could be found. Pipewall thickness was far more than today.
Increased knowledge on heavy metal 'leakage' from som copper alloys has since limited the allowed use and narrowed the band of alloys allowed. The commercial cost and availabiity of copper materials, and weaker, more thinwalled standards combined with the availability and pricing of alternative materials (stainless, plastic composites and GRP) will together contribute to a very limited use, and only for special applications. Therfore: no special reason to include copper in standards or descriptions for 'mains'.
(If selecting, be sure to check against allowance regarding heavy metal deposits and water quality.)
RE: Copper Pipe as Water Main
RE: Copper Pipe as Water Main
Water will have either a tendency to form scale or to corrode the pipe. However, the preferred approach for municipalities is to have a water with slight scaling tendencies.
For carbonate to be present in water, the water will have to have a relatively high pH. Most waters do not have a pH high enough for carbonate to be present. If there is no carbonate present in the water, it is impossible to have copper carbonate scale form no matter how many years the pipe is in service.
The easiest method to make municipal water less corrosive is to raise the pH. However, most municipal systems refuse to do this because of the expense.
Copper is more susceptible to corrosion than other materials and that as well as cost takes copper out of consideration.
I seriously doubt that the German experience is any different than anywhere else.
RE: Copper Pipe as Water Main
RE: Copper Pipe as Water Main
Michalbrch,
You say that copper is not allowed because it will dissolve in PH lower than 7, is that fact or just your interpretation of the German building codes? If anyone is aware of any studies to this effect, I'd love to learn more.
RE: Copper Pipe as Water Main
RE: Copper Pipe as Water Main
RE: Copper Pipe as Water Main
RE: Copper Pipe as Water Main
NOte that water scale for the most part consists of calcium carbonate or magnesium carbonate, not copper carbonate.
As to the pH of water, that is just one factor in corrosion. A water having a pH of 7 will tend to be corrosive if the hardness is low and the water salts are several hundred mg/l.
There is also another factor with copper corrosion. Unlike most other materials, copper is susceptible to erosion ahould the fluid velocity exceeds 8 ft/sec.
You can find information on copper at copper.org
RE: Copper Pipe as Water Main
RE: Copper Pipe as Water Main
You noted that any fluid velocity over 8 ft/s can result in excessive erosion in the pipe. Just curious where you got that number (don't mean to hijack the post, just have a possible issue within our system where excessive flows through a smaller diameter pipe may cause this erosion with higher velocities)
Thanks!
RE: Copper Pipe as Water Main
2.Water at high velocity.
An undersized piping system or an oversized recirculating pump may cause high water velocity. Installation of a smaller capacity pump(s) or a throttling bypass on the existing pump(s) should help in lowering the velocity of the water in the system. The recommended maximum velocity for water in a copper tube system is 5 - 8 feet per second (fps) for cold water systems, 4 - 5 fps for hot water systems < 140º F, and 2-3 fps for hot water systems with a temperature greater than 140º F.
http://www.copper.org/applications/plumbing/techco...