Water, water, everywhere....

73 responses total.

Sigh...I finally called a plumber after doing my own work for years. We
were sitting in the kitchen Thursday night when a drip started from the
ceiling...a quick run found a leak from a pipe going to a tub valve in
a pipe cupboard on the second floor. There was a shutoff valve, so I
studied the problem, and decided that the coupling between the pipe and the
faucet assembly had developed a hairline crack. What with a 30 year old
house and a family that insisted they had to have a shower ASAP, and
expecting that if I took the cracked coupling to a hardware store they
would laugh and say "we haven't seen one of those in years!".....I called
a plumber Friday a.m. He came within two hours, was thin enough to fit into
the pipe cupboard, and had an assortment of couplings in his tookbox, one
of which was OK - presto, 15 minutes of work and it was done. It wasn't
cheap, but it was fast and good. I have been feeling a bit ashamed of
not having tried to do the job myself, though.... At least I diagnosed
the problem so the plumber did not have to spend time finding it - and
I waited on him with light and tools, so my self respect is still somewhat
intact...   8^}.

I've done similar calls to professionals.  When I replaced my outdoor faucet,
I got stuck on a tee made from a *huge* chunk of brass, which I couldn't get
hot enough to make a reliable connection.  The plumber had a nice, hot
acetylene torch which made quick work of it.

Imagine the look on my face when I had it all together and the water back on,
then managed to pull the connection apart with my bare hands.  ;)

Wet?

Sweating pipe with a propane  torch can be difficult at times.   Water
in the pipe can make it very difficult since the water has to boil off
before the pipe will get hot enough to melt the solder.   However, the
only time so far that I had to resort to a hotter flame was when I was
trying to silver solder a 1" copper pipe on an air conditioning system
I was helping install.  I got enough heat by using a MAP  gas cylinder
instead of a propane cylinder.  Propane will also burn hotter if burnt
it with pure oxygen instead of air.

Well, the usual (recent) stampted copper sleeves were easy to sweat into a
solid connection.  But propane can only generate so much heat...

We are running a revent through a wall and wonder how far back from the front
of the studs the pipe is supposed to be.  If it is 1.5", we only have 1.5"
space for the PVC, which is slightly bigger.  Can we use copper in that area,
and how do we join it to PVC?  For electrical it is 1 1/4" spacing from the
front of the studs, is plumbing the same?  If so, we can shave the studs.

I don't think plumbing has to be 1.5" behind the front of the stud like
electrical.  Otherwise one couldn't run pipe larger than 1/2" through
a stud wall between two rooms.  They even sell 3" shc 30 pipe that has
an OD of just under 3.5" for running through 2X4 stud walls.  Either
way, the plumbing inspector can answer that.  I do know that you have
to use nail plates where pipe runs through studs.
 
You can join PCV to Cu with couplings they sell just for that purpose.

(I've started plumbing my house this week too.  Lots to learn!)

Klaus, if you finish your plumbing this week and have leftover PVC cement,
we need just a little bit to do the vent stack where it goes through the
atttic insulation.  Does anyone else have a little extra cement?  We are not
exactly running piping through studs but between two sideways studs.

Sure, it's out at the house but I will make a point to bring it back with
me today.  You also need to use primer.  If the inspector sees that you
didn't (The primer as a stain in it so he can tell.) he'll make you do
it over again.  (I'm sure you knew that.... Just wanted to make sure.)

Many thanks, but make sure you are finished with your plumbing first, we are
not in a big hurry and can insulate the front of the house first.  Where
should we pick it up in Ann Arbor when you are sure you don't need it?

Does anyone know the name of the material used for house sewers, probably some
sort of asbestos cement product, that the tree roots are always growing
through.  And what years was it used in Ann Arbor, so we can tell if we have
it (in a 1947 house).

Might that be Orangeburg (sp?)?  It's what the guy who inspected my house was
talking about when he mentioned sewer lines that go bad.  (I probably don't
have it in my 1950 house).

I don't remember what it is called, however I think it was used in the 60's.

Thanks, Jim thought it was Green-something.  He is safe.

        I don't know a name but I think they were just clay crocks.

My father called it Orangeburg tile.  We had it in a 1948 house, replaced
the sewer line in 1983.

Was it clay tile or asbestos-fiber cement?  (Orange or grey?).  We have a 1947
house where the sewer needs routing every year from tree roots.  If it is clay
tile, how would the roots be getting through, at the joins?

Usually. We've had that problem, but our sewer pipe is iron (Ithink.....).
I put a slug of copper sulfate (purchasable in hardware stores locally for
this purpose) down the line once a year when root growth should be
at its most prolific. I do worry (a little) about a) copper sulfate attacks
iron by electrochemical replacement, and b) the copper sulfate will kill
microflora in the sewage until it gets diluted. On the other hand, copper
is an essential element for plant growth, and it is also precipitated
as insoluble copper sulfide in the sewage treatment plant, I figure 
limited use is non-detrimental w.r.t. b). Now a).....

We just snake it out once a year (after the sewer backs up into the basement).
The neighbors borrow our snake.  Did you know you can get replacement tips
for the snake that bolt on at Wolverine Supply?  (They did not know, we had
to call the manufacturer).  The tip only pokes a hole through, putting a cage
made of expanded metal bolted on to the tip snags the hair-type roots, but
this has not been necessary for a while, since they started removing the last
of the elm trees.  The replacement trees have not grown big enough yet.
How long do you think the copper would have to sit in the pipe for any
noticeable attack on the iron?  And isn't there copper in the water anyway
from everyone's copper piping or is it too dilute to matter?  (Or safely
coated with precipitated calcium compounds).

Essentially no copper enters the water supply from copper piping. Copper
is quite inert in a non-acidic system. There is a greater hazard from the
lead in the solder that used to be used for copper tubing in homes. 

It is nearly 100 feet from our sewer cleanout in the basement to the
street drain. We have had it routed out several times in the past. I
figure its worth the ca. $60 for them to use their heavy duty motor
driven equipment (and do the cleanup). 

I flush the copper sulfate crystals into the line with a few gallons of
water, and leave it for a few hours. I think the main effect is to diffuse
a CuSO4 higher than the plant roots can stand into the crevices through
which they enter. But I really don't know the degree of attack on the iron.
It takes a week or so for a nail to dissolve in CuSO4 solution....the
short treatments I use should not be too server.

The city water treatment plant told us they intentionally leave the water
somewhat alkaline to avoid dissolving the copper.  
Can you describe what happens at the sewer treatment plant, I have not been.
What happens with drains over 100' long, are there routers made?

Briefly...at the sewage treatment plant the sewage is filtered to remove
shoes, dead rats, and other large debris, and then digested with bacteria.
This can be done partly anaerobilically, to produce methane, which can be
used as fuel to run the plant, but eventually the sewage is digested
with bacteria aerobically, which is a much more thorough digestion of
the organic matter (called BOD = biological oxygen demand). The resulting
slurry is filtered and the sludge (solids) landfilled or used as a soil
conditioner, and the liquid is disinfected and discharged. This describes
primary (first filtration) and secondary (digestion) treatment. Tertiary
treatment can destroy all the chemicals that still remain in the effluent
by either combusting them with oxygen (in solution), or by treatment in
constructed wetlands (converting the remaining nutrients to cattails, etc.)

Does Ann Arbor sell its sludge to tree farms?  Does it practice tertiary
treatment, and what cities do (if you know).  We also do anaerobic and then
aerobic treatment of our compost - it sits in closed buckets for a while,
where it starts stinking (or freezes over the winter) but this seems to not
interfere with the later aerobic composting.  Any problems that you know of
with this method, as long as the fermented stuff gets buried deeply?

There was an article in the A^2 Observer a few months ago that covered
A^2's water & sewage system pretty well.  (Though it focused more on
the people & pipes between the treatment plants.)

A few communities practice tertiary treatment, mostly in arid regions.
I forget the city names, but some reuse all their sewage water and not
just as "gray water" - it goes back into the water mains. Some use
constructed wetlands for tertiary treatments, and some use hyperbaric
oxygen. I left out another option of sewage sludge - incineration. 

I recall sludge being put on plants in California, but usually not on
fresh vegetables. Cotton, feed corn, and the like, are OK. The sludge
is sterilized, but people would still object. 

Home treatment of sewage with septic tanks used to be common. Septic
tanks with overflow to drain fields is still common in rural areas. This
is a combined anaerobic/aerobic treatment, and does not have high capacity
for the volume. Resorts often have aerobic treatment with spray ponds.

It is hard to do an efficient job on a small scale. 

Ann Arbor does have a big sludge pond between the Wines/Forsythe schools and
M-14.

That is NOT a sludge pond.  It is a settling pond used by the water
treatment plant, not the sewage treatment plant.  The water treatment
plant uses it when there is a high demand.  They pump water, mixed
with lime, into it during the night and draw off of it during the day
when the demand is greater than what their pumps can pump out of the
river and wells scattered around the city.  This pond is located only
slightly below the level of the treatment plant, located just on the
other side of Newport on Sunset.

I always wondered how septic tanks and drain fields work.
I thought there was a problem with heavy metals being concentrated in sludge
and that it was therefore never used for even feed crops.
Can someone give me more details on septic tanks, and do they ever need to
be cleaned out?

Klaus, that "settling pond" is the "sludge pond" for the hardness removed
from the water - it isn't sewage sludge, but it is still called "sludge". 
Lime is added to the water, and this precipitates temporary hardness as
calcium carbonate. That is what they pump to the "sludge pond". I wouldn't
have thought they would use it for water storage - they'd draw sludge back
into their system if they did. Did they tell you it was used for water
storage? 

Heavy metals don't "concentrate" in sewage sludge, but any large city has
industries connected to the sanitary sewer system, who discharge wastes
containing lots of noxious things. Metal plating (especially chrome)
plants dispose of chromium and zinc wastes, which show up in the sludge.
Some plants take up the chromium - others don't. Chromium is not good for
you. They are not supposed to dispose of chromium in the sanitary sewers,
but the city can't be everywhere, testing all waste streams. 

Septic tanks do need to be pumped when the solids put into them that are
not "liquified" by bacteria accumulate to too high a level. Companies do
this for a fee - and I know a spot where one waste hauler used to dump the
waste in the woods - with the farmer's permission (I think he was paid to
permit this). I think it was legal at the time - now they must take it to
a sewage treatment plant.

Since the topic was sewage, I didn't want people thinking that the pond
behind Wines school contained sewage.  You are correct, Rane, both are
sludge.  I should have referred to it as a reservoir for the water
treatment plant.  The shore along that pond is white from what I suspect
is lime.  The mixing of the lime with the untreated water is done at the
treatment plant.  That is also where they dredge the sludge tanks for the
precipitate, etc.  These tanks contain dredgers that constantly dredge the
the bottoms of the tanks.  I don't know why there is lime in the pond.
Perhaps the water in that pond has already been through the lime treatment
and there is a little residual lime left that settles out in the pond over
time?  I'm not even sure if the pond is still being used.  It doesn't seem
to be very well maintained any more.

I now recall that they stopped using it because it was full. Lime is
mixed with raw water in large tanks on the premises, and this precipitates
out the temporary hardness. The reaction is

          Ca(HCO3)2 (temp hardness) + Ca(OH)2 = 2CaCO3 + 2H2O

They have a fluidized bed lime kiln in the plant (or did), but stopped
using it some time ago because it was more economical to buy lime than
to reprocess their sludge. The latter was done at ca. 1800 F to carry
out the reaction

          CaCO3 + heat = CaO + CO2

The lime, CaO, was then slaked to form Ca(OH)2, by adding water, before
mixing with raw water. 

No matter how they do it, the plant is a net producer of CaCO3 sludge,
so it has to go somewhere. I believe that pond is full, as I said. They
may keep water in it to prevent CaCO3 dust from being picked up by
the wind and spreading around (harmless, but a nuisance).

Can the CaCo3 sludge (limestone) be sold to whoever produces the CaO?  Or to
a company that produces agricultural lime, or is that something different?

No, because of economics. They produce it at a very low rate, requiring
employees, storage, multiple handling, etc. Making lime from limestone at
a quarry is a high production rate operation, even with the cost of
subsequent shipping. There were several lime recovery plants in Michigan
at one time, for water treatment (Ann Arbor and Lansing), and papermaking
(Muskegon), but new lime is now cheaper. 

I will have to remember that question for the next time I go there
annual open house.

So where does the limestone sludge go now?  CAn it be used directly to add
to fields that need more alkaline soil, or are there not around here?

I don't know. They have it hauled away, but where and for what purpose
can be something that changes monthly, depending on the cost. 

With this being the Water Plumbing Item, I have another question:

Those who have done any amount of plumbing have probably run into a little
fitting called a "dielectric union".  The purpose of this fitting is to
electrically isolate copper plumbing from iron plumbing.  If one puts
these two metals in water they form a very weak battery.  None the less,
if you allow these to metals to touch current will flow from one to the
other.  This energy is not free because the metals react and will, with time,
cause premature failure of the fitting, put excessive rust in your water
or plug up the iron pipe with scale and rust.  To prevent these two metals
from touching, dielectric unions are used.

The most common place to see / use these unions is on top of a hot water
heater that is plumed to copper pipe.  It's even required by code.  Looking
at the total picture, however, I don't see how they can do any good.  Bare
in mind that code also requires all metal plumbing to be grounded to earth
ground.

Take a typical electric hot water heater installation.  The hot water
heater has an iron tank so we put dielectric unions on the nipples that
bring in cold water and take out hot water, just as the code says me
must.  Next we wire up the heater to the electric supply and turn on
the water and the electricity and after a few hours take a nice hot
shower.  Even the inspector approved the installation.

Here is the sticky point:  The dielectric unions are suppose to isolate
the iron in your hot water heater from the copper in your plumbing
sustem.  However, when you connect the power to the heater you are also
required to tie the heater to earth ground!  In so doing you have 
connected the iron in the heater to the copper in your plumbing and
rendered the dielectric union ineffective!  Dielectric currents now
use the common ground connection instead of the plumbing connection and
corrosion will happen as if no dielectric union were used in the first
place!  Even a gas fired hot water heater is tied to ground through the
gas line and flue pipe.

Am I missing something?  Is the burner or heating element electrically
isolated from the tank?  Am I off on the purpose of dielectric unions
and how they work?

I just checked my gas water heater, and the entering hot and cold pipes
do have plastic separators between the copper piping of the house and the
steel piping of the water heater. I measured the voltage across that,
and it was 0.000, and in confirmation the resistance was also only an
ohm or two. 

So a "battery" exists. However the two electrodes are separated by a
finite distance (between 1 mm and 1 cm?). I think that offers enough
resistance that the electrolysis current is too small to be of concern.
However if the copper and the steel touched, the separation distance
is zero, and a large electrolysis current could flow *at* the the
junction (through the water). 

I checked my, as of yet, unattached electric and gas hot water heaters.
The tank on the gas heater was connected to the metal gas regulator
and every other metal part that made up the heater.  The tank on the
electric heater was connected to the ground screw on the electric box
as well as every other metal part on the electric hot water heater.
i.e. the tanks on my two hot water heaters were not electrically iso-
lated.

I'm also in process of doing the following experiment:  I have three
similar containers filled with a similar amount of Ann Arbor tap water.
I the first container I put a small ring of 3/4" copper pipe and a 
bright (Not coated) 1 1/2" finishing nail, not touching.  In to the
second container I placed a small ring of 3/4" copper pipe soldered
to a bright 1 1/2" finishing nail.  In to the third container I placed
a short ring of 3/4" copper pipe and a bright 1 1/2" finishing nail
attached to each other with a wire.  The nail and copper ring are
separated by >1" and the wire was not underwater.  I also measured the
potential between the the copper ring and the steel nail at about 
300 mv and a current of about 16 uA.

It has been about four days since I started this experiment and it is
very obvious that the the nails electrically connected to the copper
are corroding *much* faster than the nail and copper ring not connected.
If anything, the nail connected but separated by >1" from the copper
ring is rusting as much as, it not more than, the nail soldered to the
copper ring.

I have yet to uncover a real purpose for dielectric unions in your
typical hot water heater installation.

- Backtalk version 1.3.30 - Copyright 1996-2006, Jan Wolter and Steve Weiss