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Dan Friedrichs
12-08-2013, 10:46 PM
Ignoring the use of chlorine, is there some reason that bacteria does (or doesn't) grow on the inside of residential water piping? Presumably, if it's wet and dark and relatively warm, something might grow?

I got thinking about this because my coffee machine has a water reservoir that I've rigged with a float valve to keep itself perpetually full (supplied by the RO water filter). I noticed the inside of the tank has developed a clear "slime". It got me thinking - what keeps that from forming on the inside of pipes?

Mike Henderson
12-08-2013, 11:36 PM
I have no real clue but I'll guess it's the chlorine. I know that in pools they use a shock of chlorine to get rid of algae when it forms.

I've taken plastic pipe out that had been used for a long time and there was nothing on the inside.

Mike

Shawn Pixley
12-09-2013, 1:22 AM
Bacteria can and does grow on the inside of pipes. Chlorine controls it at safe levels. The only times you really need to worry about it is when there isn't a regular flow through them. The more crevasses (joints) where a colony can form the worse it will be. Plastic piping systems in boats or other similar systems where the water flow is relatively stagnent are particularly susceptable. It likely that some plastics have bacterialcides built in.

Dan Friedrichs
12-09-2013, 9:26 AM
I imagine that chlorine is the answer, but then I started wondering about the water that comes out of filtration systems (RO and similar). These ostensibly remove the chlorine - does that leave the them susceptible to bacterial growth? If I connect the ice maker or water dispenser in my refrigerator to a chlorine-free water supply, what keeps it from growing "stuff"?

Prashun Patel
12-09-2013, 9:35 AM
Isn't that why there's pvc and cpvc? cpvc (at least in my town) is mandated for potable water supply. The pvc DRAINS in my sinks certainly grow all kinds of stuff. I always thought cpvc was treated to make bacteria hard to grow in there. I also thought copper has this property naturally. Wrong?

Steve Rozmiarek
12-09-2013, 9:37 AM
Us private well users usually don't use chlorine, and it doesn't kill us (usually...). The slime is likely a harmless algae that occurs naturally.

When you pull a well, or do old plumbing repairs, its surprising how much stuff is actually growing there. Municipal wells are no different. Don't worry about it.

Art Mann
12-09-2013, 9:38 AM
Bacteria can't grow in the absence of nutrients. Plastic, copper or iron doesn't offer much of a growth medium. The tank in the coffee maker probably contains dust, coffee residue, soap residue and other materials suitable for a growth medium. There is no way to avoid getting enough contaminants from the atmosphere to grow bacteria in an open container of water. Distilled water in a plastic jug will exist without bacteria almost indefinitely.

Rich Engelhardt
12-09-2013, 9:43 AM
:rolleyes:Great......

Something else to keep me awake @ night worrying about....:eek::p

Harold Burrell
12-09-2013, 10:06 AM
Don't worry about it.

Hey! You gotta die from somethin',right???

Just yesterday someone was telling me that I should be tested for sleep apnea. They said that they knew someone who died from it. I said, "Let me get this straight...There is a chance that I may be able to die someday in my sleep? And I'm supposed to not want that??? Is there a better way to go?"

We do tend to worry about stuff, don't we? If you think about it, we are all basically on "Comfort Care". The doctors are only trying to keep us comfortable until it is our time.

Morbid? Maybe...but true.







OK. End of hijack. Carry on...

Steve Rozmiarek
12-09-2013, 10:21 AM
Hey! You gotta die from somethin',right???



LOL, thats true!

We had a repair to a leaking underground water line take a bad turn on the farm. The backhoe cut a water line and a sewer line in the same hole. It was not clear whether contamination of the water pipes occurred, but to be safe, I installed softeners, reverse osmosis systems and ultra violet treatment filters to kill any nastiness. There is a way to make your water "pure" if you want.

Gordon Eyre
12-09-2013, 10:25 AM
Could the lack of oxygen in a closed system be the reason?

Brian Elfert
12-09-2013, 10:44 AM
Clear water pipes exposed to sunlight can grow nasty stuff inside the pipe. PEX is the primary type of clear pipe, but PEX shouldn't be exposed to UV either so this shouldn't be an issue for anyone.

Myk Rian
12-09-2013, 11:37 AM
You ought to see the inside of your hot water tank.
Talk about gross-out.

Dan Hintz
12-09-2013, 4:10 PM
Could the lack of oxygen in a closed system be the reason?

Nopers... plenty of dissolved oxygen in water.

John McClanahan
12-09-2013, 4:52 PM
Pressurizing the water reduces bacteria growth. The higher the pressure, the more bacteria resistant it is.

John

ray hampton
12-09-2013, 4:57 PM
HOW often do your fire dept. flush the fire hydrant to remove build-up, any build-up could be remove when the pipes are expose to running water, add fine sand to the water and sand the inside of the pipe clean

Scott T Smith
12-09-2013, 8:37 PM
Bacteria can and does grow on the inside of pipes. Chlorine controls it at safe levels. The only times you really need to worry about it is when there isn't a regular flow through them. The more crevasses (joints) where a colony can form the worse it will be. Plastic piping systems in boats or other similar systems where the water flow is relatively stagnent are particularly susceptable. It likely that some plastics have bacterialcides built in.


This has been my experience as well,.

When there is low or irregular flow (such as at weekend cabins or camps), there can definitely be some nasty stuff that can develop on the inside of the water systems pipe, especially if you are on well water. Typically it is addressed by a process called "shocking the well", which involves pouring a some bleach into the well, running the faucets long enough to get the chlorinated water throughout your system, and then leaving it in place for 24 hours. After the time is up, you flush the system for 20 minutes or so (usually when the water first comes out it is really black and nasty looking - I've seen it so bad that it looks like used motor oil).

Lots of information is available if you do a search on "shocking a water well".

Jeff Erbele
12-10-2013, 3:22 AM
Isn't that why there's pvc and cpvc? cpvc (at least in my town) is mandated for potable water supply. The pvc DRAINS in my sinks certainly grow all kinds of stuff. I always thought cpvc was treated to make bacteria hard to grow in there. I also thought copper has this property naturally. Wrong?

CPVC is a cousin to PVC. The short version is CVPC will withstand higher temperatures over time. It is rated to 190*F to 200*F depending on what you read on the inter-web. Skip those conflict and read the pipe (its printed on each stick). Neither CPVC or PVC is treated.
http://www.commercial-industrial-supply.com/resource-center/whats-the-difference-between-pvc-and-cpvc-pipe/

Biofilm will grow in copper as well.

Jeff Erbele
12-10-2013, 3:30 AM
Ignoring the use of chlorine, is there some reason that bacteria does (or doesn't) grow on the inside of residential water piping? Presumably, if it's wet and dark and relatively warm, something might grow?

I got thinking about this because my coffee machine has a water reservoir that I've rigged with a float valve to keep itself perpetually full (supplied by the RO water filter). I noticed the inside of the tank has developed a clear "slime". It got me thinking - what keeps that from forming on the inside of pipes?

Your slim is called biofilm.
A biofilm is a collection of organic and inorganic, living and dead material collected on a surface


Here are two references that address the topic:

Water Quality and Health Council
http://www.waterandhealth.org/drinkingwater/safewater.html

World Health Organization
http://www.who.int/water_sanitation_health/dwq/HPC10.pdf