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3.3 Simulation Program
Simulations exercises were conducted for both inbound and outbound ships. In addition to the Susan Maersk, a 132,000 dwt tanker (875 ft in length and 144 ft beam) heading inbound to Tosco Refinery was added to the simulation program. Containerships pulled bow-in to the Howland Hook Terminals and backed out of the channels for outbound scenarios. Existing condition containership runs were accomplished using the SL Performance.
Track plots of the Susan Maersk, heading inbound to the Howland Hook terminals are shown in Figure 14. These track plots show the pilots having little difficulty bringing the larger Susan Maersk into the deepened Arthur Kill Channels.
Figure 14. Susan Maersk, inbound ebb tide, Plan 2
Track plots of the Susan Maersk; backing out of the Howland Hook terminals are shown in Figure 15. This was a fairly difficult maneuver due to the long backing distance. Pilots typically requested three 4000 HP tugs for backing maneuvers. The ships completing this exercise were able to successfully back out and turn in Newark Bay.
Figure 15. Susan Maersk, outbound ebb tide
A detailed description of all simulator results for Arthur Kill is beyond the scope of this paper. Full results are included in the projects technical report (Webb, in preparation).
3.4 Arthur Kill Recommendations
The deepening of the Arthur Kill channels had no impact upon tankers transiting the reach to call at Tosco refinery.
Simulation results indicate that either Plan 1 or Plan 2 of the proposed deepened channel will be adequate for inbound runs. However, backing these large ships out of Arthur Kill is a slow and tedious process. The track plots show that the Plan 1 simulations were fairly successful when compared to the existing runs. However, it was obvious during observation of these simulation exercises that the pilots were having difficulties with the dogleg to the south on the eastern end of North of Shooter's Island Reach. Therefore, Plan 2, which straightened the eastern end of North of Shooter's Island Reach was recommended.
4. ARTHUR KILL DREDGE LOCATIONS
4.1 Project Description.
CENAN is preparing to dredge the Arthur Kill channels to -41 ft mlw to Howland Hook, and -40 ft mlw to Tosco. Several areas of the channel are rock bottom and will require blasting. Once blasted, the loose material will decrease the channel depth in that area. To avoid placing draft restrictions on ships transiting the Arthur Kill channels, CENAN is planning to buoy off portions of the channel width (Figure 16). The portion of the channel not buoyed off will remain at -35 ft mlw.
Figure 16. Buoyed channel
ERDC conducted a navigation study utilizing real-time ship simulation modeling to evaluate the proposed dredging plan for four of the contract areas. These four areas (Area A2, Areas B, Area D6, and Area K1) are shown in Figure 17. Model development and online testing occurred at the ERDC in Vicksburg, MS during the period from June to November 2002. Area B consisted of three buoy lines, areas B1, B2, and B3.
Figure 17. Dredge Locations A-D.
4.2 Database Development.
The simulation models for the dredge location study were the existing condition models form the Arthur Kill 50 ft deepening project. Figure 18 shows the simulation of the inbound SL Performance passing the dredge in area A2.
Figure 18. SL Performance passing dredge.
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