During
the
19th
and
early
20th
century
lead
was
used
very
widely
in
the
major
cities
of
the
U.S.
for
water
pipes
because
of
its
durability
and
malleability.
It
was
also
the
major
source
of
lead-related
health
problems
in
the
years
before
the
health
hazards
of
ingesting
lead
were
fully
understood;
among
these
were
stillbirth
and
high
rates
of
infant
mortality1.
Lead
pipes
were
superceded
by
galvanized
steel
and
copper,
and
copper
pipe
became
the
predominant
material
selected
for
domestic
water
service
and
distribution
in
residential
construction
after
World
War
II.
Copper
pipe
still
has
over
80%
market
share
for
new
indoor
plumbing2
with
galvanized
pipe
and
plastics
being
alternatives.
Lead
Some
old
homes
and
particularly
the
service
lines
from
the
water
mains
to
the
homes
still
have
lead
pipes.
For
example,
Providence
Water
in
Rhode
Island
announced
in
May
2007
that
some
25,000
of
its
total
of
74,000
water
connections
are
made
of
lead
and
will
be
replaced
over
a 15
year
period3.
According
to
the
Federal
government4,
“Lead
is
unusual
among
drinking
water
contaminants
in
that
it
seldom
occurs
naturally
in
water
supplies
like
rivers
and
lakes.
Lead
enters
drinking
water
primarily
as a
result
of
the
corrosion,
or
wearing
away,
of
materials
containing
lead
in
the
water
distribution
system
and
household
plumbing.
These
materials
include
lead-based
solder
used
to
join
copper
pipe,
brass
and
chrome
plated
brass
faucets,
and
in
some
cases,
pipes
made
of
lead
that
connect
your
house
to
the
water
main
(service
lines).”
In
1986,
Congress
banned
the
use
of
lead
solder
containing
greater
than
0.2%
lead,
and
restricted
the
lead
content
of
faucets,
pipes
and
other
plumbing
materials
to
8.0%.”
This
so-called
“lead-free”
brass
can
still
legally
contain
up to
8%
lead
and
plumbing
systems
installed
prior
to
1986
can
contain
high
levels
of
lead
from
both
plumbing
components
and
lead
solder.
The
presence
of
lead
in
water
from
the
tap
is
indicative
of
serious
pipe
corrosion
that
must
be
corrected
for
health
reasons.
Galvanized
pipes
Galvanizing
of
steel
pipes
involves
the
application
of
molten
zinc
to
pre-formed
steel
pipes
to
provide
a
corrosion
resistant
coating.
However
many
galvanized
pipes
in
old
buildings
were
manufactured
using
zinc
that
probably
contained
high
levels
of
lead,
which
is a
common
impurity
in
the
zinc.
It
was
not
until
1986
that
the
Wheatland
Tube
Company
became
the
first
galvanized
pipe
manufacturer
to be
certified
to
ANSI/NSF
Standard
61
for
its
hot
dip
galvanized
pipe.
Galvanized
pipes
are
still
common
in
older
homes
and
many
commercial
buildings.
Galvanized
pipes
will
corrode
over
time,
as
indicated
by
the
following
corrosion
symptoms:
 |
high
levels
of
zinc
or
iron
in
tap
water |
|
a
“metallic“
taste
of
the
water |
|
poor
water
flow
due
to
blockage
from
mineral
buildup |
|
discolored
water
(brown,
red
or
yellow
water) |
Copper
pipes
Copper
is
widely
used
for
plumbing
pipes
because
of its
excellent
corrosion
resistance
and
safety.
It is
also
very
easy to
work
with:
it is
malleable
and
easily
joined
by
fittings
or
soldering.
Copper
plumbing
pipe
comes
in
three
types:
|
Type
K:
has
the
thickest
walls |
|
Type
L:
walls
are
less
thick
than
K,
but
thicker
than
M |
|
Type
M:
has
the
thinnest
walls.
Also,
Type
M
is
a
hard
tube,
not
easily
bendable
and
is
only
supplied
in
straight
lengths.
It
is
most
commonly
used
as
the
lowest
cost
tube
in
new
buildings. |
Despite
its
success
as a
plumbing
material,
copper
pipe
has
sometimes
failed
well
before
its
design
lifetime,
mainly
because
of pinhole
leaks.
This
subject
has
been
extensively
studied
for
many
years.
Dr.
Marc
Edwards
of the
Virginia
Polytechnic
Institute
and
State
University
(Virginia
Tech)
believes
and has
testified
during
hearings
of the
U.S.
House
of
Representatives
and at
City
Council
Hearings
of the
District
of
Columbia
government
that
pinhole
leaks
in
copper
pipes
are a
major
national
problem.
1. W.
Troesken,
National
Bureau
of
Economic
Research,
NBER
Working
Paper
No.
W9549,
2003
2.
Copper
Development
Association
3.
Providence
Water,
Press
Release
May 24
2007
4. Code
of
Federal
Regulations
(CFR
Chapter
1, Part
141,143)
