Calcasieu Ship Channel Traffic Study (Port of Lake Charles)

Calcasieu Traffic Study – Base Case Results | 20 June 2014 | 1
Calcasieu Traffic Study
Base Case Results
Matthew von Schilling | 20 June 2014

Table of Contents
1. Introduction
2. Key Simulation Results
3. Traffic Year Results
4. Detailed Results
5. Pilot and Tug Requirements
6. Conclusions

1 Introduction

Purpose and Background
Ausenco was engaged by the Port of Lake Charles to conduct a simulation study of the capacity of
the Calcasieu Ship Channel.
• Traffic in the channel is expected to increase significantly over the next 10 years due to the expanded
operations of the existing terminals and the construction of various proposed facilities. Vessel traffic is
forecasted to increase by over 50% in the next five years and to double by 2023.
• This increased traffic could have a significant impact on the operations of the channel and may require
changes to the channel infrastructure to avoid significant congestion and delays.
• Ausenco developed a detailed simulation model of the Calcasieu Ship Channel to investigate the
present and future channel capacity and assess the need for changes to the channel operations and
infrastructure.

Simulation Model Screenshot
The figure below shows a screenshot of the Calcasieu Ship Channel simulation model.

Simulation Model Scope
The Calcasieu Ship Channel simulation model included the following details:
• The Outer Bar and Inner Channel, from the CC buoy to the I-10 bridge.
• 19 existing and proposed terminals (over 30 berths) along the channel.
• Current and forecasted piloted vessel traffic to each terminal, from 2013 to 2033.
• Vessel transit rules: one-way traffic, passing restrictions, separation time between vessels, and
exclusion zones for LNG vessels.
• Convoys, which gave priority to vessels calling at terminals further up the channel.
• Inbound and outbound pilot boarding windows.
• Wind and visibility restrictions.
• Pilot and tug requirements.
The inputs for the model are discussed in detail in the Inputs and Assumptions document.1
1Ausenco, Calcasieu Ship Channel Traffic Study – Revised Draft Report: Inputs and Assumptions Section, June 2014

1,022
1,108
1,153
1,189
1,322
1,668
1,914
2,039
2,121 2,121
2,183 2,184 2,191
2,237 2,241 2,249 2,249 2,249 2,249 2,249 2,249
0
500
1,000
1,500
2,000
2,500
2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033
NumberofVesselCalls
Total Number of Piloted Vessel Calls (Vessel Mix)
Large LNG
Small LNG
Deep Draft
Wide
Narrow
Simulation Model Inputs
Vessel Traffic from 2013 to 2033
• Traffic forecasts for 2014 to 2033
were provided by the current and
future channel users.
• The vessels in the simulation model
were grouped into five categories –
Large LNG, Small LNG, Deep
Draft, Wide and Narrow.
• The majority of the increased traffic
was LNG carriers to the proposed
terminals.
• Deep Draft vessels that were laden
inbound and laden outbound are
discussed separately in the results,
since they were subject to different
boarding windows.
Annual traffic in the channel is expected to increase from 1,000 vessels in 2013 to over 2,000 vessels
in 2020.

Simulation Methodology
The simulation model was used to evaluate the traffic in each year – from 2013 to 2033 –
independently.
• Each traffic year was individually modeled as a unique “simulation run”. Within each simulation run, the
traffic for the year was repeated 40 times – to produce 40 simulated years – and each time with different
weather and environmental conditions. This repetition was done to provide a sufficient amount of
variability in the model outputs.
• The outputs from each simulation run were analyzed to determine statistics and conclusions about the
channel operations for each traffic year (based on the 40 repetitions).
• The results detailed in this presentation represent the “base case” simulation model – that is, the model
with the existing channel infrastructure and operational rules.
o The results provided assume a sufficient number of Pilots and tugs in the channel – these numbers
are discussed in detail in Section 5.

Key Performance Indicators
Two key performance indicators (KPIs) were used to assess the capacity of the channel and the
impact of increased traffic: the number of vessel calls and the vessel wait time.
• The number of vessel calls indicated whether the channel was capable of handling the scheduled traffic.
• Vessel wait time was a measure of how much vessels were delayed waiting to enter the channel and
represented the effect of congestion on operations. Although the channel may be capable of handling
increased traffic levels, the additional delays incurred may not be acceptable to the channel or the users.
• Inbound wait time for a vessel was counted from the time it was assigned a berth and ready to enter the
channel, and was equal to the time a vessel waited at the pilot boarding area due to opposing traffic,
government regulations, boarding windows, wind, visibility, and Pilot and/or tug availability.
• Outbound wait time for a vessel was counted from the time it had finished all loading or unloading
activities and was ready to depart, and was equal to the time a vessel waited at berth for suitable
conditions as noted immediately above.
• Combined wait time was the sum of the inbound and outbound wait time.

Wait Time Statistics
Detailed statistics for wait time were produced by the simulation model and are detailed in this
presentation.
• The wait time experienced by each individual vessel in the entire simulation was an output of the model.
Statistics about the overall wait times were calculated from an analysis of the individual wait times.
• The median (or 50th percentile) wait time is primarily used in this presentation because it represents the
delays for a “typical” vessel. Other statistics – namely, the minimum, 25th, 75th and 99th percentiles –
provide a distribution of the operations.
• These statistics are identified on box and whisker diagrams:
• The 99th percentile is shown on the figures as the peak value rather than the 100th percentile (the
absolute maximum). This was done because each simulation run had a few vessels that experienced
excessively long delays which in practice could be reasonably managed and mitigated by the channel.
99th Percentile
75th Percentile
Minimum
25th Percentile
Median

Structure of Results Sections
The results of the traffic year simulation runs are detailed in several sections:
• Key Simulation Results: presents the results for the 2013, 2018, and 2023 traffic years. These traffic
years represented the operations of the channel over the next ten years, when traffic is expected to
increase significantly, and provide a general overview of the study results.
• Traffic Year Results: presents the results for each traffic year (from 2013 to 2033) to show when and
how the wait time increased with additional traffic.
• Detailed Results: presents detailed outputs for the 2018 and 2023 traffic cases to identify the potential
key causes of wait time in the channel.
• Pilot and Tug Requirements: presents the number of Pilots and tugs required for the channel for each
traffic year.

2 Key Simulation Results

2.3 h 4.6 h 6.8 h
0
24
48
72
96
120
144
2013 2018 2023
CombinedWaitTime(h/vessel)
99th Percentile
75th Percentile
Median
25th Percentile
Minimum
Key Performance Indicators
Comparison of 2013, 2018, and 2023 Traffic Years
• The figure shows the wait time
statistics for all vessels in 2013,
2018, and 2023.
• The median wait time increased
from 2.3 hours in 2013 to 6.8 hours
in 2023, as a result of the additional
traffic in the channel.
• The table shows that the channel
was able to handle all of the
scheduled vessel traffic in all three
traffic years.
• The results indicate that while the
Calcasieu Ship Channel is capable
of handling all of the additional
traffic, vessels calling at the
channel will typically experience
higher wait times.
Year
Number of
Vessels
Scheduled
Number of
Vessels
Handled
2013 1,022 1,022
2018 1,668 1,668
2023 2,183 2,183

Wait Time by Vessel Category
Comparison of 2013, 2018, and 2023 Traffic Years
• The figures show the wait time for
each of the modeled vessel
categories in 2013, 2018, and
2023.
• The median wait time increased by
3.1 to 4.0 hours between 2013 and
2023 for the vessel categories
present in both traffic years.
• The Large LNG carriers had the
highest wait times out of all vessel
categories in both 2018 and 2023.
3.5 h 2.6 h 1.3 h
0
24
48
72
96
120
144
201399th Percentile
75th Percentile
Median
25th Percentile
Minimum
8.8 h 5.5 h 6.6 h 2.1 h 4.1 h 3.1 h
0
24
48
72
96
120
144
2018
12.3 h
7.5 h 8.6 h 3.1 h 5.7 h 4.6 h
0
24
48
72
96
120
144
Large LNG Deep Draft
(Laden Inbound)
Deep Draft
(Laden Outbound)
Small LNG Wide Narrow
2023

3 Traffic Year Results

0
24
48
72
96
120
144
2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033
Total Wait Time Distribution by Year
99th Percentile
75th Percentile
Median
25th Percentile
Minimum
Wait Time for All Vessels
Each Traffic Year from 2013 to 2033
• The figure shows the wait time
statistics for all vessels for each of
the traffic years.
• The median wait time increased
from 2.3 hours in 2013, to 4.6 hours
in 2018, and to 6.8 hours in 2023.
• The 99th percentile wait time
increased from 31.0 hours in 2013,
to 50.8 hours in 2018, and to
67.2 hours in 2023.
• The wait time for all vessels
followed the same trend as the
increase in traffic (as shown on
Slide 7).

0
6
12
18
24
2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033
MedianCombinedWaitTime(h/vessel)
Combined Wait Time by Vessel Type
Large LNG
Deep Draft (Laden Inbound)
Deep Draft (Laden Outbound)
Small LNG
Wide
Narrow
All Vessels
Wait Time by Vessel Category
• The figure shows the median wait
time for each vessel category for
each traffic year.
• The Large LNG carriers had the
largest increase in median wait time
– from 6.4 hours in 2017 (the first
year in which they are expected to
call at terminals in the channel) to
12.3 hours in 2023.
• The wait time for all other vessel
categories increased moderately as
the traffic increased.
• The wait time in a given traffic year
was highest for the most-restricted
vessel categories – Large LNG
carriers and Deep Draft vessels.

4 Detailed Results

Detailed Wait Time Results for Vessel Categories
The wait times for each vessel category were analyzed in detail to determine which aspects of the
channel were the cause of delays.
• Each vessel category was subject to different rules and restrictions that governed when vessels could
enter the channel.
• The following slides show the wait times for each vessel category and for each month. The comparison
between vessel categories allowed the identification of particular causes of wait time, and the monthly
breakdown allowed an assessment of seasonal causes.
• It is somewhat difficult to assign an exact cause to delays experienced by any single vessel because
delays are often subject to knock-on effects. For example, a vessel may be delayed initially due to
opposing traffic, and then further delayed by a missed boarding window or weather (or by multiple
conditions at the same time).
• The results are shown for the 2018 and 2023 traffic cases because these represented key years for
traffic increases and provided suitable indications for the causes of wait time.
• Since the Large LNG carriers and Deep Draft vessels were the two most restricted vessel categories,
the majority of comparisons are made between these categories.

5.6 h 3.3 h 3.1 h 2.8 h 1.4 h 0.9 h 1.2 h 1.5 h 1.1 h 1.7 h 1.9 h 2.5 h0
24
48
72
96
120
144
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
99th Percentile
75th Percentile
Median
25th Percentile
Minimum
Wait Time by Month | 2018 Traffic Year
Inbound Wait Time for Large LNG Carriers & Deep Draft Vessels
• The figures show the inbound wait
time in 2018 for Large LNG carriers
and Deep Draft vessels that were
laden on their inbound transit.
• Although both vessel categories were
restricted by the same inbound
boarding windows, the Large LNG
carriers had consistently higher
median wait times.
• The passing restrictions for LNG
carriers on the Outer Bar as well as
the more restrictive wind limit likely
resulted in the overall higher wait time
throughout the year.
• The median wait times for both vessel
categories varied seasonally (lower in
summer months and higher in winter
months), which was the result of wind
and visibility delays.
9.2 h 5.9 h 6.2 h 5.7 h 2.8 h 2.7 h 2.6 h 2.4 h 2.0 h 3.5 h 3.0 h 6.2 h
0
24
48
72
96
120
144
InboundWaitTime(h/vessel)
Large LNG

3.3 h 4.8 h 6.0 h 2.5 h 1.9 h 2.8 h 1.7 h 1.4 h 1.5 h 3.0 h 3.6 h 6.5 h
0
24
48
72
96
120
144
OutboundWaitTime(h/vessel)
Large LNG
Outbound Wait Time for Large LNG Carriers & Deep Draft Vessels
• The figures show the outbound wait
laden on their outbound transit
(since these vessels were subject
to the same outbound boarding
windows as the Large LNG
carriers).
• Similar to the previous slide, there
was a distinct seasonality that was
attributed to weather.
• The median wait time was higher
for the Deep Draft vessels than the
Large LNG carriers. These Deep
Draft vessels called at terminals
further upstream than the Large
LNG vessels, and were subject to
more delays.
7.4 h 7.9 h 6.7 h 3.7 h 3.2 h 4.7 h 2.8 h 4.4 h 4.3 h 4.1 h 4.7 h
11.8 h
0
24
48
72
96
120
144
99th Percentile
75th Percentile
Median
25th Percentile
Minimum

Combined Wait Time for All Other Vessels
• The three figures show the
combined wait time in 2018 for the
three other vessel categories –
Small LNG carriers, Wide vessels,
and Narrow vessels – that is, those
that were not restricted by inbound
and outbound boarding windows.
• The wait times for these three
vessel categories were much lower
than those for Large LNG carriers
or Deep Draft vessels.
• Although the wait times had some
seasonality, it was not as
pronounced as for the other vessel
categories.
3.3 h 3.3 h 3.0 h 2.4 h 1.1 h 1.3 h 1.1 h 1.5 h 1.4 h 2.8 h 2.5 h 2.6 h0
24
48
72
96
120
144
Small LNG
5.5 h 5.5 h 5.8 h 4.2 h 2.9 h 2.9 h 3.0 h 3.2 h 3.2 h 4.7 h 4.7 h 4.9 h
0
24
48
72
96
120
144
Wide
99th Percentile
75th Percentile
Median
25th Percentile
Minimum
4.8 h 4.6 h 4.6 h 3.6 h 2.1 h 2.2 h 2.4 h 2.0 h 2.2 h 3.6 h 3.8 h 3.9 h0
24
48
72
96
120
144
Narrow

Inbound Wait Time for Large LNG Carriers & Deep Draft Vessels
• The figures show the inbound wait
laden on their inbound transit.
• As was seen in the results for 2018,
the median wait times for both
vessel categories varied seasonally
and the Large LNG carriers had
consistently higher median wait
times.
13.0 h 9.3 h 9.7 h 8.5 h 5.4 h 3.6 h 4.1 h 4.0 h 3.3 h 5.4 h 6.0 h 7.8 h
0
24
48
72
96
120
144
InboundWaitTime(h/vessel)
Large LNG
8.5 h 4.5 h 5.6 h 4.4 h 2.8 h 2.0 h 2.4 h 3.1 h 2.1 h 2.8 h 3.5 h 4.3 h0
24
48
72
96
120
144
99th Percentile
75th Percentile
Median
25th Percentile
Minimum

Outbound Wait Time for Large LNG Carriers & Deep Draft Vessels
• The figures show the outbound wait
laden on their outbound transit.
the median wait time was higher for
the Deep Draft vessels than the
Large LNG carriers.
4.3 h 5.1 h 6.9 h 3.6 h 2.7 h 3.4 h 2.2 h 2.3 h 2.8 h 3.4 h 4.1 h 8.7 h
0
24
48
72
96
120
144
OutboundWaitTime(h/vessel)
Large LNG
7.3 h 7.9 h 8.4 h 6.8 h 5.0 h 4.8 h 3.5 h 4.3 h 4.5 h 4.5 h 7.1 h 11.0 h
0
24
48
72
96
120
144
99th Percentile
75th Percentile
Median
25th Percentile
Minimum

Combined Wait Time for All Other Vessels
• The three figures show the
combined wait time in 2023 for the
Small LNG carriers, Wide vessels,
and Narrow vessels.
the wait times for these three
vessel categories were much lower
than those for Large LNG carriers
or Deep Draft vessels.
4.1 h 3.9 h 4.2 h 3.3 h 2.3 h 2.2 h 2.3 h 2.4 h 2.1 h 3.8 h 3.4 h 3.8 h0
24
48
72
96
120
144
Small LNG
7.6 h 6.9 h 7.3 h 6.1 h 4.5 h 4.3 h 4.4 h 4.4 h 4.5 h 6.6 h 6.9 h 6.6 h
0
24
48
72
96
120
144
Wide
99th Percentile
75th Percentile
Median
25th Percentile
Minimum
6.2 h 6.0 h 6.2 h 5.4 h 3.5 h 3.3 h 3.4 h 3.2 h 3.4 h 4.7 h 5.6 h 5.7 h
0
24
48
72
96
120
144
Narrow

Summary of Detailed Wait Time Results
The monthly statistics demonstrated that wait time was highly seasonal for certain vessel
categories and that the Large LNG carriers experienced the highest combined wait times.
• The wait times for all vessel categories were seasonal which was attributed to the wind and visibility
delays. The Large LNG carriers, the most restricted vessel category, had the most pronounced
seasonality.
• Weather delays are difficult to mitigate and as traffic increases in the channel, such delays will have a
more significant impact and result in higher wait times.
• Weather delays create knock-on effects, however, which could be mitigated. After a delay ended, there
was often a queue of vessels waiting to enter or exit the channel, and any additional restrictions on the
queued vessels – boarding windows, passing, etc. – increased the time before the backlog could be
cleared.
• Any changes to the channel operations and infrastructure that would allow vessels to move more freely
(longer boarding windows, passing lanes, revised LNG exclusion zones, etc.) would likely reduce wait
times for all vessels in the channel.
• It is also expected that changes that only directly decrease wait times for one vessel category (e.g.
changing passing restrictions for LNG carriers) will have a secondary impact and decrease wait times
for all other vessel categories.

Several vessels per year experienced excessive wait times. The figure below demonstrates a
series of events that prevented a vessel from entering the channel, and shows how wait time can
be the result of multiple causes.
Example of a Long Wait Time
Worst Case (100th Percentile) Scenario

5 Pilot and Tug Requirements

Pilot Requirements
Each modeled vessel required at least one Lake Charles Pilot on board to transit the Calcasieu
Ship Channel.
• There are currently 17 Pilots employed by the Port of Lake Charles.
• The Pilots have restrictions on continuous working hours and required break periods, as well as a limit
to the number of working hours in a year.
• The exact number of hours the Pilots will work in each year in the future was not known at the time of
the study, so the number of Pilots required was determined for limits of 700, 800, and 900 working hours
per year.
• For the simulation model, the working hour limits were assumed to be a hard limit – that is, the Pilots in
the model were unable to exceed this limit. As such, if the modeled channel had an insufficient number
of Pilots, then it was unable to handle the scheduled vessel traffic.

0
5
10
15
20
25
30
35
40
45
50
55
2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033
NumberofPilotsRequired
Channel Pilot Requirements
700 h/y Pilot Working Hour Limit
Pilots Required in 2018:
700 h/y:
800 h/y:
900 h/y:
36
32
28
700 h/y:
800 h/y:
900 h/y:
49
43
38
700 h/y:
800 h/y:
900 h/y:
22
19
17
Number of Pilots Required
• The figure shows the number of
Pilots required to handle the
modeled traffic in the channel for
each traffic year and for the three
different working hour limits.
• The number of Pilots required
varied between 17-22 in 2013 to
38-49 in 2023, which was roughly
proportional to the increase in
traffic.
• The real Calcasieu Ship Channel
employed 17 Pilots in 2013.

Channel Tug Requirements
Each modeled vessel required two assist tugs to transit the Calcasieu Ship Channel.
• The channel currently has 7 assist tugs, which is equivalent to 3 tug “sets” (with the 7th tug available as
a spare).
• All of the LNG terminals were assumed to provide their own dedicated tugs, so the LNG carriers in the
simulation model did not require the use of the channel tugs.
o The tug requirements for the LNG terminals were not known at the time of the study, nor were the
rules for shared usage for the dedicated LNG terminal tugs, so the tug usage for these terminals
could not be accurately modeled.
• Unlike the Pilots, if the channel had an insufficient number of tugs, it could still be possible to handle all
of the scheduled traffic, albeit with additional delays. That is, the number of tugs did not impose a hard
limit on the number of vessels that could be handled.
• Simulation runs with different numbers of tug sets were performed to determine how the number of tugs
impacted vessel wait time and to assess the need for additional tugs.

Number of Channel Tugs Required
Vessel Wait Time for 2013, 2018, and 2023
• The figure shows the wait time for
the vessels which required channel
tugs (i.e. non-LNG vessels) in
2013, 2018, and 2023 when the
modeled channel had different
numbers of tug sets.
• The results are shown for
simulation runs with 3 and 4
channel tugs sets, as well as with
unlimited tug sets.
• The results indicate that an
increased number of channel tugs
did not significantly reduce vessel
wait time.
2.4 h 2.2 h 2.2 h 4.2 h 3.9 h 3.8 h
5.7 h 5.3 h 5.2 h
2013 2018 2023
0
24
48
72
96
120
144
3 Tug Sets
(Present)
4 Tug Sets Unlimited
Tug Sets
3 Tug Sets
(Present)
Tug Sets
3 Tug Sets
(Present)
Tug Sets
Wait due to Tugs
99th Percentile
75th Percentile
Median
25th Percentile
Minimum

6 Conclusions

Overall Conclusions
The results of the base case simulation runs showed that the channel was capable of handling the
forecasted traffic levels up to 2033, although the increased traffic was subject to longer wait times
that may need to be mitigated.
• For each traffic year, the channel was capable of handling the scheduled number of vessels.
• Wait time increased for all vessels as traffic increased, although Large LNG carriers experienced the
most significant increase in wait time.
• The overall wait time increased, and if the amount indicated by the model is considered unacceptable –
for example, if the typical wait times experienced by the present traffic needs to be maintained – then
changes to the channel operations or infrastructure should be investigated.
• The discussion of results focused on median wait time (the wait time for a typical vessel), but the long
wait times caused by multiple sources could impact production capabilities at the terminals and may
need to be considered as well.
• The channel will require a significantly higher number of Pilots to handle the forecasted additional traffic.
• The current number of channel tugs is likely sufficient for the channel (assuming the LNG terminals
provide their own dedicated tugs) since additional tugs did not significantly reduce wait time.

Next Steps
The next major step for the study is to determine which sensitivity cases to perform.
• Each sensitivity case can be used to investigate changes to the channel operations to determine if they
improve the wait time as intended. Results can be compared between sensitivity cases to attempt to
identify the “optimal” changes.
• Some potential changes which could be investigated in the study are:
o Changes to LNG exclusion zone restrictions and passing rules (on the entire channel or just on the
Outer Bar)
o Passing lane(s) (location(s) and length(s) to be determined)
o Anchorages (specific locations to be determined)
o A salt water barrier
o Revised boarding window rules (if possible)
o Combinations of the above
The other remaining steps for the simulation study are:
• Produce report detailing results of the base case and sensitivity cases.
• Prepare user interface for simulation model.

Calcasieu Ship Channel Traffic Study (Port of Lake Charles)

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