1Hutson,
S.
S.,
N.
L.
Barber,
J.
F.
Kenny,
K.
S.
Linsey,
D.
S.
Lumia,
and
M.
A.
Maupin.
2004.
Estimated
Use
of
Water
in
the
United
States
in
2000.
U.
S.
Geological
Survey
Circular
1268.
Background
Information
for
Peer
Review
of
Aspects
of
Benefit
Analysis
for
Phase
III
of
the
316(
b)
Rulemakings
1.
Background
on
Section
316(
b)
Rulemakings
Nationwide,
over
1,500
facilities
withdraw
large
volumes
of
water
from
U.
S.
surface
waters
to
cool
their
operations.
These
facilities
are
located
on
a
variety
of
waterbody
types,
including
lakes,
rivers,
estuaries,
and
other
coastal
waters,
at
a
number
of
locations
throughout
the
United
States
(
see
Figure
1).
EPA
is
currently
developing
regulations
for
these
facilities
under
section
316(
b)
of
the
Clean
Water
Act
(
33
U.
S.
C.
1251
et
seq.).
Section
316(
b)
addresses
cooling
water
intake
structures
and
requires
that
"
the
location,
design,
construction,
and
capacity
of
cooling
water
intake
structures
reflect
the
best
technology
available
for
minimizing
adverse
environmental
impact."
EPA's
intent
is
to
set
technology­
based
performance
standards
that
minimize
the
environmental
impact
of
cooling
water
intake
structures
by
reducing
impingement
and
entrainment.
Impingement
takes
place
when
organisms
are
trapped
against
the
outer
portion
of
an
intake
by
the
force
of
water
withdrawal.
Entrainment
occurs
when
organisms
are
drawn
through
the
intake
structure
and
into
the
cooling
system
where
they
are
subject
to
thermal,
physical,
and
chemical
stressors.
Both
processes
cause
injury
or
death
to
hundreds
of
species
of
aquatic
organisms.

The
316(
b)
rulemaking
is
divided
into
three
phases:


Phase
I
rule,
governing
new
facilities,
was
published
on
December
18,
2001.


Phase
II
rule,
governing
existing
facilities
whose
primary
activity
is
to
generate
and
transmit
electrical
power
and
with
a
design
intake
flow
of
at
least
50
million
gallons
per
day
(
MGD),
was
published
on
February
16,
2004.


Phase
III
rule,
governing
existing
electric
power
producers
not
covered
by
the
Phase
II
rule
and
all
manufacturing
facilities
was
proposed
on
November
1,
2004.
EPA
must
make
a
final
decision
and
issue
a
final
regulatory
action
by
June
1,
2006.

Of
the
approximately
408
billion
gallons
of
water
a
day
that
are
withdrawn
from
the
surface
waters
of
the
United
States
for
cooling,
irrigation,
manufacturing,
drinking,
livestock
watering
and
other
purposes1,
EPA
estimates
approximately
237
billion
gallons
of
water
a
day
are
withdrawn
for
the
purposes
of
cooling.
Of
this
amount,
EPA
estimates
that
facilities
addressed
in
2US
EPA.
2004.
National
Pollutant
Discharge
Elimination
System
­
Final
Regulations
to
Establish
Requirements
for
Cooling
Water
Intake
Structures
at
Phase
II
Existing
Facilities;
Final
Rule.
Federal
Register
69:
41586.
http://
www.
epa.
gov/
waterscience/
316b/
ph2.
htm
3US
EPA.
2004.
National
Pollutant
Discharge
Elimination
System
 
Proposed
Regulations
to
Establish
Requirements
for
Cooling
Water
Intake
Structures
at
Phase
III
Facilities;
Proposed
Rule.
Federal
Register
69:
68465.
http://
www.
epa.
gov/
waterscience/
316b/
ph3.
htm
4
For
more
information
on
proposed
regulatory
options.,
see:
US
EPA.
2004.
National
Pollutant
Discharge
Elimination
System
 
Proposed
Regulations
to
Establish
Requirements
for
Cooling
Water
Intake
Structures
at
Phase
III
Facilities;
Proposed
Rule.
Federal
Register
69:
68465.
http://
www.
epa.
gov/
waterscience/
316b/
ph3.
htm
5
More
information
on
EPA's
draft
benefits
analysis
for
the
Phase
III
rule,
see:
US
EPA.
2004.
Economic
Analysis
for
the
Proposed
Section
316(
b)
Rule
for
Phase
III
Facilities.
http://
www.
epa.
gov/
waterscience/
316b/
ph3docs/
p3p_
ea.
pdf
the
Phase
II
rule
withdraw
214
billion
gallons
of
water
a
day
and
facilities
addressed
in
the
Phase
III
rule
withdraw
23
billion
gallons
of
water
a
day.
2,3
2.
National
Benefits
Analysis
In
developing
regulations
for
Phase
III
facilities
under
section
316(
b),
EPA
is
examining
a
variety
of
regulatory
options
to
reduce
impingement
and
entrainment
at
these
facilities.
4
As
part
of
this
examination,
EPA
is
developing
an
estimate
of
the
national
economic
benefits
that
may
result
from
each
of
these
options.
The
benefits
analysis
ultimately
expresses
benefits
from
each
of
the
options
in
terms
of
dollars.
Estimates
are
used
both
to
assess
each
option
and
to
compare
the
options
with
each
other.
5
EPA
must
complete
a
final
benefits
analysis
during
the
next
several
months
in
order
to
meet
the
court­
ordered
deadline
of
June
1,
2006
for
a
final
action
on
the
Phase
III
rule.

To
support
the
benefits
analysis,
it
is
necessary
to
determine
the
current
environmental
impact
of
facilities
with
cooling
water
intake
structures
and
the
reduction
in
impact
that
is
expected
to
occur
with
each
different
regulatory
option.
An
approach
common
in
fisheries
assessment
and
management
and
known
as
a
"
yield
per
recruit"
model
was
used
for
the
Phase
II
benefits
analysis
and
for
the
proposed
Phase
III
rule.
EPA
is
now
evaluating
the
utility
of
a
population
model
based
on
an
age­
structured
projection
matrix,
as
described
in
Newbold
and
Iovanna
(
2004).
The
sections
below
discuss
aspects
of
the
data
available
for
implementing
these
models.
Also
provided
is
an
overview
of
the
main
features
and
data
requirements
of
the
yield
per
recruit
model
used
by
EPA
for
the
previous
316(
b)
benefits
analyses.
A
more
detailed
description
of
this
model
is
available
in
Section
A1­
4.2
of
Chapter
A1
of
USEPA
(
2004).

3.
Available
Data
3.1
Impingement
and
Entrainment
Data
The
available
impingement
and
entrainment
data
are
facility­
derived
counts
of
organisms
impinged
and
entrained.
Nationwide,
hundreds
of
different
species
are
subject
to
impingement
and
entrainment.
These
species
are
listed
in
appendices
to
Parts
B­
G
of
USEPA
(
2004).
Figure
1
shows
Phase
III
facilities
for
which
precise
location
information
is
available
(
out
of
an
estimated
universe
of
683
Phase
III
facilities
total).
Most
of
the
facilities
that
are
in
scope
of
the
Phase
III
rule
are
located
on
lakes
and
rivers.
Figure
1
also
shows
the
locations
of
facilities
that
have
conducted
impingement
and
entrainment
studies
of
sufficient
quality
to
be
used
in
EPA's
analysis.
Facility
studies
were
excluded
from
EPA's
analysis
if
the
information
reported
was
not
suitable
for
the
models
used
by
EPA,
which
require
annual
loss
rates
expressed
on
a
species­
and
age­
specific
basis.
Studies
were
also
excluded
if
they
did
not
sample
all
of
the
facility's
intakes,
or
indicate
how
to
extrapolate
from
the
sampled
intakes
to
those
not
sampled.
Additional
details
on
the
available
impingement
and
entrainment
data
are
provided
in
Section
A1­
3.1
of
Chapter
A1
of
USEPA
(
2004).

Some
facilities
count
impingement
and
entrainment
losses
throughout
the
year,
but
usually
impingement
and
entrainment
is
monitored
only
during
months
when
the
greatest
number
of
organisms
are
thought
to
be
vulnerable
to
a
facility's
intakes.
Facility
documents
sometimes
indicate
how
losses
for
part
of
the
year
should
be
extrapolated
to
obtain
an
annual
loss
rate,
but
in
most
cases
it
is
necessary
to
assume
that
seasonal
counts
reasonably
approximate
the
total
annual
loss.
Facility
documents
rarely
include
per
capita
impingement
and
entrainment
mortality
rates.

There
is
no
standard
protocol
for
sampling
impingement
and
entrainment,
so
impingement
and
entrainment
loss
estimates
are
not
necessarily
comparable
across
facilities.
Many
factors
can
influence
the
accuracy
of
impingement
and
entrainment
estimates,
including
the
efficiency
of
the
sampling
gear,
but
these
factors
are
seldom
accounted
for
in
loss
records.
Facility
impingement
and
entrainment
monitoring
is
also
generally
limited
in
duration
and
decades
old.

Only
a
subset
of
facilities
with
cooling
water
intake
structures
have
collected
impingement
and
entrainment
data,
and
in
many
cases
losses
for
only
a
subset
of
the
species
impinged
and
entrained
are
counted.
Most
of
the
species
counted
are
fish
species,
and
most
of
these
are
forage
species.
Macroinvertebrate
losses
are
rarely
counted.
Figure
1.
Locations
of
in
scope
Phase
III
facilities
and
model
facilities
used
for
impingement
and
entrainment
estimates.

3.2
Life
History
Data
Both
of
the
modeling
approaches
being
examined
for
this
peer
review
require
species­
and
stagespecific
rates
of
growth,
natural
mortality,
and
fishing
mortality.
Ideally,
growth
and
mortality
rates
would
be
obtained
from
a
comprehensive,
site­
specific
monitoring
program.
However,
few
facilities
with
cooling
water
intake
structures
have
collected
site­
specific
life
history
information.
Therefore,
it
is
usually
necessary
to
obtain
literature
values
for
growth
and
mortality
rates
from
other
populations
of
the
same
or
similar
species.
The
scientific
literature,
stock
assessments,
the
online
database
FishBase,
and
local
fisheries
experts
are
sources
of
this
information.
However,
all
of
these
data
sources
have
limitations.
There
are
fewer
life
history
data
available
for
freshwater
species
and
species
that
are
not
harvested.
Stock
assessments
are
available
for
some
exploited
species,
but
they
usually
do
not
consider
early
life
stage
mortality,
durations
of
early
life
stages,
or
stage­
specific
fecundity.
Even
if
mortality
rates
of
early
life
stages
are
considered,
they
are
difficult
to
measure
with
precision.
Moreover,
few
studies
measure
all
relevant
parameters
simultaneously.
In
addition,
the
available
data
may
not
always
be
for
similar
geographic
locations
and
ecological
settings
as
those
in
which
the
are
species
impinged
and
entrained,
and
they
seldom
indicate
how
rates
may
vary
as
environmental
conditions
change
or
as
a
function
of
potential
density
dependent
effects.
In
addition
to
growth
and
mortality
rates,
population
modeling
also
requires
estimates
of
reproductive
rates,
population
growth
rates,
and
current
population
sizes.
Unfortunately,
this
information
is
usually
only
available
for
exploited
species.
However,
even
for
exploited
species
that
have
been
extensively
studied
it
can
be
difficult
to
define
a
discrete
population
for
impact
assessment
purposes.
For
example,
species
such
as
Atlantic
menhaden
move
in
and
out
of
estuaries
over
a
broad
geographic
range
that
includes
multiple
facilities
with
cooling
water
intake
structures.
It
is
also
not
clear
how
to
use
fisheries
monitoring
data
to
determine
the
spatial
extent
of
harvested
populations
affected
by
impingement
and
entrainment.
The
densities
of
organisms
in
the
vicinity
of
facilities
with
cooling
water
intake
structures
are
also
not
well­
characterized.
Thus,
in
most
cases
there
is
a
lack
of
empirical
information
on
the
total
size
of
the
affected
population
or
even
the
size
of
the
population
of
larvae
within
the
zone
of
influence
of
the
intake.

4.
Yield
Per
Recruit
Model
Currently,
EPA
estimates
changes
in
yield
resulting
from
changes
in
impingement
and
entrainment
by
first
converting
losses
of
different
life
stages
of
fish
to
an
equivalent
number
of
one­
year
olds,
and
then
using
a
yield
per
recruit
model
to
estimate
the
lifetime
yield
of
the
cohort
of
one­
year
old
fish
that
would
have
been
produced
had
they
not
been
impinged
and
entrained.
The
yield­
perrecruit
model
is
based
on
the
Thompson­
Bell
model
used
in
assessments
of
exploited
fish
species
(
Ricker,
1975).
The
general
procedure
involves
multiplying
age­
specific
harvest
rates
by
age­
specific
weights
to
calculate
an
age­
specific
expected
yield.
The
lifetime
expected
yield
for
a
cohort
of
fish
is
then
the
sum
of
all
age­
specific
expected
yields.

It
is
important
to
note
that
the
yield
per
recruit
model
projects
increases
in
yield
resulting
from
reductions
in
impingement
and
entrainment
through
the
life
of
the
cohort
only;
it
does
not
consider
potential
long­
term
changes
in
population
size
or
fish
population
dynamics.
The
method
is
described
in
detail
in
section
A1­
4.2
of
Chapter
A1
of
U.
S.
EPA
(
2004).

The
yield
per
recruit
method
addresses
the
indirect
use
value
of
forage
fish
by
calculating
the
production
foregone
of
these
individuals
and
transferring
this
production
to
the
yield
of
harvested
species.
Production
foregone
is
the
expected
total
amount
of
future
growth
in
biomass
of
the
individuals
that
were
impinged
or
entrained,
had
they
not
been
impinged
or
entrained.
Forage
species
production
foregone
is
added
to
the
foregone
yield
of
harvested
species
using
a
simple
trophic
transfer
model.
Details
of
these
calculations
are
presented
in
sections
A1­
4.3
and
A1­
4.4
of
Chapter
A1
of
U.
S.
EPA
(
2004).

The
major
assumptions
of
the
yield
per
recruit
model
are
that:


Species­
and
stage­
specific
growth
and
mortality
rates
are
known
and
constant

Literature
values
for
natural
mortality
include
mortality
due
to
impingement
and
entrainment

The
yield
from
a
cohort
of
fish
is
proportional
to
the
number
recruited.

The
assumption
that
natural
mortality
and
fishing
mortality
are
constant
implies
that:


Impingement
and
entrainment
losses
are
a
relatively
minor
source
of
mortality
in
comparison
to
the
total
effects
of
all
other
sources
of
natural
mortality

For
most
fish
stocks,
the
scale
of
changes
in
impingement
and
entrainment
loss
rates
being
considered
will
not
lead
to
dramatically
large
increases
in
the
size
of
harvestable
stocks.

For
EPA's
analysis,
loss
rates
are
calculated
for
facilities
in
each
region
with
suitable
impingement
and
entrainment
data.
Suitable
data
include
species­
and
life­
stage
specific
losses
by
year.
Rates
for
facilities
with
data
are
extrapolated
to
facilities
in
the
same
region
without
data
on
the
basis
of
intake
flow
to
derive
an
estimate
of
the
total
loss
in
each
region.
The
estimated
regional
impingement
and
entrainment
totals
are
then
summed
to
obtain
an
estimate
of
the
relative
magnitude
of
losses
nationwide.
Details
of
the
extrapolation
method
are
provided
in
section
A1­
5
of
Chapter
A1
of
U.
S.
EPA
(
2004).
Structural
and
parameter
uncertainties
are
discussed
in
Chapter
A2.
Literature
Cited
Hutson,
S.
S.,
N.
L.
Barber,
J.
F.
Kenny,
K.
S.
Linsey,
D.
S.
Lumia,
and
M.
A.
Maupin.
2004.
Estimated
Use
of
Water
in
the
United
States
in
2000.
U.
S.
Geological
Survey
Circular
1268.

Newbold,
S.
and
R.
Iovanna.
2004.
Population­
level
Impacts
on
Fish
of
Cooling
Water
Withdrawals.

Ricker,
W.
E.
1975.
Computation
and
interpretation
of
biological
statistics
of
fish
populations.
Fisheries
Research
Board
of
Canada,
Bulletin
191.

US
EPA.
2004.
Economic
Analysis
for
the
Proposed
Section
316(
b)
Rule
for
Phase
III
Facilities.
http://
www.
epa.
gov/
waterscience/
316b/
ph3docs/
p3p_
ea.
pdf
US
EPA.
2004.
National
Pollutant
Discharge
Elimination
System
 
Proposed
Regulations
to
Establish
Requirements
for
Cooling
Water
Intake
Structures
at
Phase
III
Facilities;
Proposed
Rule.
Federal
Register
69:
68443­
68565.
http://
www.
epa.
gov/
waterscience/
316b/
ph3.
htm
US
EPA.
2004.
National
Pollutant
Discharge
Elimination
System
­
Final
Regulations
to
Establish
Requirements
for
Cooling
Water
Intake
Structures
at
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