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Man With a Cat
11-16-2005, 08:10 PM
First, understand I'm not looking for a "what's in my drinking water" type of answer.

It's this: Let's say, I'm a developer planning and building a subdivision where I'll get municipal water - no well/septic here.

Before I can put up homes, I have to do groundwork and infrastructure. Bury utilities, grade the land, stuff like that. Now when I'm getting ready to lay the buried pipe for my domestic water - the water that's going to come out of faucets someday - I get the pipe delivered to my work site. There it sits, oh say a few weeks while the trench is dug and the pipe gets connected and buried.

While it's there waiting, it's exposed to elements, and pretty much anything that falls on, in or around it. Let's say a vole, or a rat climbs in, gets chased by a cat and dies, or just takes a big vole-dump or something. Then the next day the pipe gets buried and becomes part of the water supply.

With the critter or what have you IN the pipe.

Now, at some point I imagine there's a process (or I hope there is) where the municipal supply is run through the pipe, and maybe dumped as a way to clear the pipe. Is there? I don't know, that's why I'm in GQ with this.

But let's say there isn't. The system is a closed loop with who knows how many voles, skunks and piles of cat turd in it. Then a house gets built, the tie in to the home is done, and some poor guy hits the shower one day and without knowing it, gets doused in water passing through pipe that's all full of nasty stuff.

Someone tell me there's a way they know to clear or sanitize or at least rinse out buried water supply before it comes out of my tap?

I'm going right now to take a shower then out for the night so an answer won't save me for now, but I am checking this thread first thing in the morning before I grab a glass of water for my AM drugs.

Si Amigo
11-16-2005, 08:17 PM
Good Morning! I went to house last night and hooked up you sewer line to your water line. Have a nice day! :D

John F
11-16-2005, 08:30 PM
Someone tell me there's a way they know to clear or sanitize or at least rinse out buried water supply before it comes out of my tap?

Nope.

Sorry about that but nope.

They just hook it up and start using it no sanitizing or anything.

groman
11-16-2005, 08:38 PM
What do you think happens to all the wildlife that drowns in your water supply before it hits your pipes but after it's cleaned?

BlakeTyner
11-16-2005, 10:31 PM
I spent most of my life with horrible well water, until last year we were finally able to get city water. Being the last house in the county, the supply line ends at my driveway. When the workers installed the line, they flushed it out for days on end before any of our houses were connected. They'd just open the valve at the end and let it flow for about 8 hours, every day, for roughly a week.

Every quarter or so they come back and do the same thing.

John F
11-16-2005, 10:45 PM
Every quarter or so they come back and do the same thing.

Are you talking about the fire main, do they flush it from a fire hydrant?

BlakeTyner
11-16-2005, 11:07 PM
There are no fire plugs, just the taps to our houses and the end of the line (basically an industrial sized spigot) on the right-hand side of my driveway.

NinetyWt
11-17-2005, 01:49 AM
Nope.

Sorry about that but nope.

They just hook it up and start using it no sanitizing or anything.

I hope you were just kidding with that answer. :dubious:

After completion of the water line system in your new subdivision, you are required to "sanitize" the line by pumping heavily chlorinated water into it. Closed off from the rest of the system, of course. Specifications dictate that this heavily chlorinated water sit in the system for a prescribed number of hours. Water samples are then taken. In our area, you must take three water samples, a few days apart, which are sent to the Department of Health.

You will not be allowed to connect to the City's system until these samples come back clean.

Further, the City itself takes water samples randomly throughout their system once a month, also sent to the state Department of Health. If any samples come back "bad", steps must be taken to correct the problem.

A.R. Cane
11-17-2005, 07:05 AM
I supervised maintenance on water distribution systems on military installations. The process is call superchlorination and it's basically as NinetyWT describes.

Man With a Cat
11-17-2005, 08:33 AM
Thanks, NinetyWt. I can rest a little easier now. Or shower at least! :D

I knew they have to test random samples, I guess I should have figured that at the very least, anything toxic would show there.

Cowgirl Jules
11-17-2005, 12:03 PM
Just posting to echo NinetyWt (again.)

Besides disinfecting new lines, they're typically flushed. The flushing happens first, because organic material interacts badly with available chlorine, reducing the amount available for disinfection and producing some byproducts.

Lines are flushed and disinfected when they're repaired too, Bus Guy.

-California Water Distribution Operator C. Jules

Man With a Cat
11-17-2005, 12:11 PM
*Raising a glass of tap water in a toast to NinetyWt & Cowgirl Jules*

Finagle
11-17-2005, 12:13 PM
Just posting to echo NinetyWt (again.)

Besides disinfecting new lines, they're typically flushed. The flushing happens first, because organic material interacts badly with available chlorine, reducing the amount available for disinfection and producing some byproducts.

Lines are flushed and disinfected when they're repaired too, Bus Guy.

-California Water Distribution Operator C. Jules


Still, and out of morbid curiosity, when they're repairing water lines (particularly old ones), what does the inside look like? Fairly pristine, modulo mineral deposits? Or stalagmites of moss and algae everywhere? Are the pipes too dark for plant life to take a foothold or do various cave dwelling types of vegetation get a foothold in there?


BTW, if the prospect of highly diluted (but sanitized) mole poop squicks you out, then you should probably avoid swimming in lakes, swimming pools and the ocean.

robby
11-17-2005, 12:59 PM
Still, and out of morbid curiosity, when they're repairing water lines (particularly old ones), what does the inside look like? Fairly pristine, modulo mineral deposits? Or stalagmites of moss and algae everywhere? Are the pipes too dark for plant life to take a foothold or do various cave dwelling types of vegetation get a foothold in there?

There's no plant life, etc. in water mains. They can still look pretty disgusting, though, depending on what the water main was constructed of.

Old water mains made of cast iron or ductile iron look pretty bad after a few decades due to corrosion. You get a build-up of corrosion products that can completely occlude the pipe.

Ductile iron is still one of the most widely used materials for new water mains. It replaced the use of cast iron (which had been used in the U.S. since the early 1800s) in the early 1970s.

Man With a Cat
11-17-2005, 01:10 PM
BTW, if the prospect of highly diluted (but sanitized) mole poop squicks you out, then you should probably avoid swimming in lakes, swimming pools and the ocean.

I know, and within reason I accept some risk. Hell, once I even didn't wash my hands after using the washroom, really.....

But there's a difference between swimming in diluted muskrat love, and making my iced tea with it.

Cowgirl Jules
11-17-2005, 02:30 PM
Still, and out of morbid curiosity, when they're repairing water lines (particularly old ones), what does the inside look like? Fairly pristine, modulo mineral deposits? Or stalagmites of moss and algae everywhere? Are the pipes too dark for plant life to take a foothold or do various cave dwelling types of vegetation get a foothold in there?


No, it's not really vegetation. No light, you know, and the chlorine (or other disinfectants, but that's what I work with) pretty much takes care of the smaller biologicals.

It's not pretty though. Besides the corrosion that robby mentioned, there are mineral deposits like calicification built up on the insides of lines. That roughens the lines, so even more sticks to the interiors, and it builds up. Also, you're really likely to find sand or dirt, even on water systems that are supplied by wells rather than open reservoirs. But it's clean dirt, at least with regards to pathogens, thanks to the disinfection and the treatment at the plants.

Many water systems have a program of cleaning out the lines with "pigs" - a mechanical sort of wad that's stuffed into the line at one end and flushed out at another, scrubbing the crud with it.

Stan Doubt
11-17-2005, 08:03 PM
It is also not unusual for water utilities in older communities to add phosphates, such as zinc phosphate, to intentionally create deposits on the inside of small service lines, which were made of lead for many years. The deposits reduce the rate at which lead leaches from the pipes and solders. Two additional things you can do to reduce lead exposure is always flush your water for a minute or two before using it after it sits in the pipes for an extended period of time and NEVER use hot water for food preparation, as hot water leaches lead much faster than cold water.

NinetyWt
11-18-2005, 01:16 AM
You get a build-up of corrosion products that can completely occlude the pipe.

Commonly referred to as "scale" in our circles. The "scale" inside elevated water tanks can reach great, crunchy proportions. Yum! :p

However, as long as the system is chlorinated regularly one doesn't need to worry about germs.

Some of the most fab things we have found over the years in the water lines: soda cans, bleached-out bird skeletons, and a wheel.

Yes, a wheel. About 4 inches in diameter, like you'd find on an appliance dolly. This discovery was made when the crews were trying to isolate a section of line - this one valve wouldn't close. They ended up cutting it out, and found this little wheel nestled under the valve. Utterly sterile, of course. ;)

Thanks for the kudos, Bus Guy but your real experts are Jules and A.R. Cane.