Cooling
Water
Intake
Structure
(
CWIS)
Information
Data
Required
Rig
Information
Rig
Name
Deepwater
Pathfinder
Deepwater
Frontier
Deepwater
Discovery
Deepwater
Millennium
Rig
Type
Drillship
(
Dynamically
Positioned)
Total
Installed
Power
Generation
Capacity
47,736
HP
Number
of
Cooling
Water
Intake
Structures
(
CWISs)
12
Brief
description
of
each
CWIS
(
e.
g.,
sea
chest,
simple
pipe)
All
CWIS
are
enclosed
within
Sea
Chests
Rough
dimensions
of
each
CWIS
and
indicate
whether
onboard
CWIS
has
an
existing
flange
Port,
aft
engine
room
#
1,
450mm
pipe,
flange
Port,
aft
engine
room
#
2,
450mm
pipe,
flange
Center,
aft
engine
rm.
#
1,
450mm
pipe,
flange
Center,
aft
engine.
rm.
#
2,
450mm
pipe,
flange
Stbd,
aft
engine
room
#
1,
450mm
pipe,
flange
Stbd,
aft
engine
room
#
2,
450mm
pipe,
flange
Fwd.
Machinery
space
#
1,
450mm
pipe,
flange
Fwd.
Machinery
space
#
2,
450mm
pipe,
flange
Port
Bow
thruster,
125mm
pipe,
flange
Port
Bow
thruster,
125mm
pipe,
flange
Ballast
Pump
#
1,
700mm
pipe
Ballast
Pump
#
2,
700mm
pipe
Screen
type
(
e.
g.,
strainer,
wedge
wire)
with
mesh
size
Port,
aft
E/
R
#
1­
2,
Seachest
grating­
25mm
Simplex
Basket
Strainers
with
6mm
perforations.
Center,
aft
E/
R
#
1­
2,
Seachest
grating­
25mm
Simplex
Basket
Strainers
with
6mm
perforations
Stbd,
aft
E/
R
#
1­
2,
Seachest
grating­
25mm
Simplex
Basket
Strainers
with
6mm
perforations
Fwd.
Machinery
space
#
1­
2,
Seachest
grating­
25mm
Simplex
Basket
Strainers
with
6mm
perforations
Port,
Stbd
Bow
thrusters
aft
E/
R
#
1­
2,
Seachest
grating­
25mm
Simplex
Basket
Strainers
with
6mm
perforations
Ballast
pumps
#
1,
2­
Seachest
grating­
25mm
Total
Design
Specifications
for
Daily
Maximum
Water
Intake
Volume
of
each
CWIS
Port,
aft
engine
rooms
#
1&
2
4,362,470
gal
each
(
16,512
m3/
day)
Center,
aft
engine
rooms#
1&
2
6,898,790
gal
each
(
6,112
m3/
day)
Stbd,
aft
engine
room
#
1
&
2
4,362,470
gal
each
(
16,512
m3/
day)
Fwd.
Machinery
spaces
#
1&
2
4,628,784
gal
each
(
17,520
m3/
day)
Port
&
Stbd
Bow
thruster
443,856
gal
each
(
1,680
m3/
day)
Pump
Rooms
#
1&
2
15,852,000
gal
each
(
60,000
m3/
day)
Total
Daily
Water
Intake
Volume
of
each
CWIS
(
Set­
up/
Drilling)
Note
1
Note
2
Port,
aft
engine
room
#
1
4,362,470
gal
Port,
aft
engine
room
#
2
Center,
aft
engine
room
#
1
6,898,790
gal
Center,
aft
engine
room
#
2
Stbd,
aft
engine
room
#
1
4,362,470
gal
Stbd,
aft
engine
room
#
2
Fwd.
Machinery
space
#
1,
4,628,784
gal
Fwd.
Machinery
space
#
2,
Port
Bow
thruster,
443,856
gal
Stbd
Bow
thruster,
443,856
gal
Ballast
Pump
#
1,
112,285
gal
Ballast
Pump
#
2,
Design
Specs
for
Through
Screen
Velocity
of
each
CWIS
(
i.
e.,
Q=
V*
A)
(
Set­
up/
Drilling)
Port,
aft
engine
room
#
1
1.64
fps
Port,
aft
engine
room
#
2
1.64
fps
Center,
aft
engine
room
#
1
2.59
fps
Center,
aft
engine
room
#
2
2.59
fps
Stbd,
aft
engine
room
#
1
1.64
fps
Stbd,
aft
engine
room
#
2
1.64
fps
Fwd.
Machinery
space
#
1
1.74
fps
Fwd.
Machinery
space
#
2
1.74
fps
Port
Bow
thruster
0.164
fps
Stbd
Bow
thruster
0.164
fps
Ballast
Pump
#
1
5.97
fps
Ballast
Pump
#
2
5.97
fps
List
of
Purposes
of
Cooling
Water
Intakes
(
e.
g.,
cool
crude
oil,
produced
water,
power
generators,
drill
pipe
brakes)
Port
#
1­
2,
,
cooling
for
central
cooler
for
port
E/
R
support
equipment
Center
#
1­
2,
cooling
for
central
cooler
for
center
E/
R
support
equipment,
atmospheric
condenser,
rig
floor
equipment
Stbd
#
1­
2
cooling
for
central
cooler
for
stbd
E/
R
support
equipment
Fwd.
Machinery
space
#
1,
#
2
cooling
for
central
cooler
for
all
drill
floor
equipment,
center
bow
thruster
and
support
equipment,
accommodation
air
conditioning
&
refrigeration,
MSD
.
Port
Bow
thruster,
cooling
for
central
cooler
for
port
Bow
thruster
support
equipment
Stbd.
Bow
thruster,
cooling
for
central
cooler
for
stbd
bow
thruster
support
equipment
List
of
Purposes
of
Non­
cooling
Water
Intakes
(
e.
g.,
fire
water,
hotel
loads)
Ballast
Pump
#
1,
2­
Ballast
water
Total
Volume
of
Water
Intake
for
Ballasting,
Duration
of
the
Ballast
intake,
and
the
Through
Screen
Velocity
of
the
Ballast
intake
Note
3
Total
volume
ballast
water
7,397,600
gal
(
28,000
m3/
well)
Duration
of
well
65
days
Velocity
3.04
fps
Mitigation
Measures
for
reducing
Exotic
Species
Migration
through
Ballast
water
The
rig
does
not
carry
much
ballast
water
from
location
to
location.
It
is
taken
on
and
dumped
at
the
same
location.
Mitigation
Measures
for
reducing
Impingement
and
Entrainment
of
Aquatic
Organisms,
as
well
as
Bio­
fouling
Prevention
Measures
Sea
chest
screens,
simplex
baskets,
cathodic
protection,
marine
growth
protection
system
Is
the
Rig
equipped
with
a
Radiator
Cooling
System
for
the
Main
Engines?
No
Note
1:
Only
one
seachest
in
each
of
the
port,
starboard,
center
and
forward
machinery
will
be
open
at
a
time.

Note
2:
Ballast
operations
are
continually
changing­
this
figure
represents
the
estimated
average
daily
ballast
intake
volume.
Only
one
pump
used
for
this
ballast
operation.

Note
3:
Figures
represent
estimated
values.
