February 2, 2005

 

The following guidelines have been developed to determine adequate Tug assistance in the Port of Houston. Similar docks have been grouped and coupled with vessel size and draft information. Assist tugs are then designated by the circumstances of the maneuver. Tugs are categorized by “bollard pull” as provided by area operators. Bollard pull is used rather than horsepower to rate tugs effectiveness. Additionally, the tug’s design type, tractor or conventional has a definite bearing on effectiveness and desirability.

 

Tug Class Ratings:

Minimum Bollard Pull (in pounds)

 

Class  

ahead                                         

astern

S (Small; compact)

35,000

20,000

M (Medium; diamond class)

60,000

45,000

L (Large; twin-screws)

85,000

55,000

T (Tractor)

 

 

 

T can substitute for any class

L can substitute for S or M

M can substitute for S except arrivals less than 30’

 

Bow thruster substitutes for smallest tug

 

Thrusters must meet the following minimum requirement of available horsepower to substitute for a tug.  (I KW equals 1.35 HP)

 

Vessel LOA

Thruster Horsepower

More than 900’

2,500

751’ – 900’

2,000

551’ – 750’

980

451’ – 550’

730

350’ – 450’

400

Less than 350’

200

 

As always any vessel specific concerns should be discussed with the Houston Pilots. Ships and the waters in which they operate represent a dynamic, ever-changing environment.  Firm rules addressing every possible scenario are not possible.  The individual pilot and master on board are best situated to evaluate the specific docking and/or undocking evolution contemplated by the vessel and the prevailing weather, current, and traffic situation affecting the vessel.  These guidelines are recommendations only.  It is recognized that the on-scene discretion of the pilot and master should not be hindered.  The following guidelines regarding tug assistance are in no way intended to limit, hinder, or override the on-scene discretion of the pilot and master as they navigate vessels on the Houston Ship Channel.  We realize that there will be situations where actions that conflict with these recommendations may be necessary to address specific situations or special circumstances that confront a specific vessel.  Further, it is recognized that the demands of maritime commence, vessel and tug design, and terminal configuration may change requiring a departure from the current tug assistance guidelines. 

 

Bayport- Odfjell/Baytank & LBC/Petro United

Vessel size

Draft

Arrival

Departure

Notes

<400’

Any

S

S

* no thruster substitute

<500’

<30’

SS

SS

 

<500’

>30’

MS

SS

 

<550’

<30’

 

S

*head out sailing-no thruster sub.

501’-650’

<30’

LS

LS

 

501’-650’

>30’

LM

LM

 

>650’

<30’

LM

LM

 

>650’

>30’

LL

LM

 

 

Barbours Cut

Vessel size

Draft

Arrival

Departure

Notes

<400’

Any

S

S

 

<500’

<30’

-

S

*head out sailing

<600’

<30’

MS

SS

 

<600’

>30’

MM

MS

 

601’-750’

<30’

LM

LM

 

601’-750’

>30’

LL

LM

* no thruster substitute

750’-900’

<30’

LL

LM

* no thruster substitute

750’-900’

>30’

LL

LL

* no thruster substitute

>900’

<30’

LLM/LT

LL

* no thruster substitute

>900’

>30’

LLL/LT

LL/LT

* no thruster substitute

 

ExxonMobil Baytown

Berth 1 & 2

Vessel size

Draft

Arrival

Departure

Notes

<500’

<30’

SS

S

* no thruster substitute

<500’

>30’

MS

M

* no thruster substitute

501’-650’

<30’

LM

MS

* no thruster substitute

501’-650’

>30’

LL

LM

* no thruster substitute

>650’

<30’

LL

LM

* no thruster substitute

>650’

>30’

LL

LL

* no thruster substitute

 

Berth 3,4,5,6

Vessel size

Draft

Arrival

Departure

Notes

<500’

<30’

SS

SS

* no thruster substitute

<500’

>30’

MM

MS

* no thruster substitute

501’-650’

<30’

LM

MS

* no thruster substitute

501’-650’

>30’

LL

LM

* no thruster substitute

>650’

<30’

LL

LM

* no thruster substitute

>650’

>30’

TLL

LL

* no thruster substitute

Widebody (Berth 6)

<34’

TLL/LLL

LL

* no thruster substitute

Widebody (Berth 6)

>34’

TLL/LLLM

LL

* no thruster substitute

Widebody (Berth 4 & 5)

<34’

TLLM/LLLL

LL

* no thruster substitute

Widebody (Berth 4 & 5)

>34’

TTLL/TLLL

TL/LL

* no thruster substitute

 

Cemex. Cargil, Houston Ammonia, Georgia Gulf Agrifos

Vessel size

Draft

Arrival

Departure

Notes

<400’

Any

S

S

 

<500’

<30’

SS

SS

 

<500’

>30’

SS

SS

 

501’-650’

<30’

LS

MS

 

501’-650’

>30’

LM

LM

 

>650’

<30’

LL

LM

 

>650’

>30’

LL

LL

 

 

Vopak, Deer Park

Vessel size

Draft

Arrival

Departure

Notes

<400’

Any

S

S

* no thruster substitute

<500’

<30’

SS

SS

 

<500’

>30’

MS

SS

 

501’-650’

<30’

LS

LS

 

501’-650’

>30’

LL

LM

 

>650’

<30’

LL

LM

 

>650’

>30’

LL

LL

 

Widebody (VoPak #3)

<34’

LL

LL

 

Widebody (VoPak #3)

>34’

TL/LLL

LL

 

 

ITC

Vessel size

Draft

Arrival

Departure

Notes

<400’

Any

S

S