VERSION DATE OF ISSUE DESCRIPTION PREPARED CHECKED APPROVED Technical note HHP DKA OYBE

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1 DRAMMENREGIONENS VIRKESTERMINALER DEVELOPMENT OF NEW TIMBER TERMINAL NAVIGATION AND BERTH LOCATION STUDY ADDRESS COWI A/S Parallelvej Kongens Lyngby Denmark TEL FAX WWW cowi.com CONTENTS 1 Introduction 1 2 Vessel requirements Design vessel (timber carrier) 3 3 Functional requirements at the timber berth Berth configuration Navigational requirements 6 4 Location: Holmen and Gilhusbukta, Drammen Approach New berth - Holmen New berth - Gilhusbukta 9 5 Location: Storsand Sandtak, Hurum Approach New berth - Storsand sandtak 10 6 Location: Mulvika, Holmestrand Approach New berth Mulvika 12 7 Summary of findings/conclusions 12 1 Introduction Following technical note, considers four locations to develop a timber gateway PROJECT NO. DOCUMENT NO. A A VERSION DATE OF ISSUE DESCRIPTION PREPARED CHECKED APPROVED Technical note HHP DKA OYBE

2 2 DEVELOPMENT OF NEW TIMBER TERMINAL export harbour in the regions west of Oslo. From the initial screening (phase 1) of suitable locations, three locations have been selected. Each of the selected locations have the potential to be developed in to a timber export terminal. Further, a fourth location have been added in the bay of Gilsbukta just east of the existing timber terminal Lierstranda. The selected locations for the timber terminal development are listed below (See also Figure 1): Storsand Sandtak(4), Hurum Municipality Holmen(7), Drammen Municipality Mulvika(13), Holmestrand Municipality Gilhusbukta (x), Drammen Municipality X: Gilhusbukta 7: Holmen 4:Storsand Sandtak 13: Mulvika Figure 1: Overview of considered locations for future timber terminal

3 DEVELOPMENT OF NEW TIMBER TERMINAL 3 The technical note has been prepared with an initial definition of the overall functional requirements for the development of a new timber terminal. Subsequent each of the four locations have been investigated for the fulfilment of the requirements. It shall be noted that only requirements related to the navigational/manoeuvring access and berth conditions have been included in the technical note. 2 Vessel requirements 2.1 Design vessel (timber carrier) A number of design vessels have been considered both for the existing conditions and for a new fully developed timber transport. The design vessels have been selected from the initial deadweight values(dwt), which have been quoted in the screening report(fase 1 Silingsprocess) Figure 2: Typical vessel for existing timber transport (dwt ton) The following table shows small design vessels, which have been considered for the existing timber transport. Vessel photo Vessel name Dwt Loa [m] B(beam) Max draft [ton] [m] [m] St. Pauli* (IMO ) Trader 2* (IMO ) *) No assistance from tug boat required for berthing and maneuvering.

4 4 DEVELOPMENT OF NEW TIMBER TERMINAL Figure 3. Typical timber carrier for the new berth (DWT approx ton) The following table shows design vessels, which have been considered for the future timber terminal with a fully developed deep sea berth. Vessel photo Vessel name Dwt Loa B(beam) Max-draft [ton] [m] [m] [m] Xing Zun Hai *(IMO ) SBI MAIA *(IMO ) Functional requirements at the timber berth 3.1 Berth configuration At the traditional timber terminal the berth length is normally equal or greater than then overall length of the vessel (Loa), because the vessel will be loaded with cranes operating along the berth or from cranes on the vessel loading or unloading directly to truck or onto the berth area(apron). The vessel will approach the berth at a small angle to the berthing line (side berthing). The berth has to be protected to secure minimum wave disturbance at berthing and during loading/on-loading of the vessel. At the investigated locations wave action is probably not a major issue, due to the natural protecting in the fjords. If the wave action is considered to a problem at the berth, it will be necessary to install a breakwater as long as the water depth is not more than 10-15m.

5 DEVELOPMENT OF NEW TIMBER TERMINAL 5 If the berth is frequently called, ice formation at the berth should not close the accessibility of the berth. It is expected that at all four locations ice formation will not be considered to be a problem for berthing. The apron area at the berth shall be reserved for temporary timber storage of logistic reasons. The loading operation on the apron area very much depends on the cranes on the vessel or the mobile harbour cranes on the berth. Figure 4 shows, four vessel cranes operating at the same time. For the smaller existing timber vessel, the majority of timber can be temporary stored at the apron area at the berth. Figure 4: Large timber terminal berth (From timber terminal Northport in New Zealand) For the future situation, two vessels should be able to call at the berth at the same time in order to have an effective berth. The minimum distance between the vessels to minimum m (0.1 x Loa). This will require a berth length of approx. 240 m (105 x x 0.1 x Loa) if two vessels are required. If only one existing vessel is required at the berth the length could be reduced to approx. 130 m ( x 0.1 x Loa). Based on above requirements regarding the vessels and the berth, the following minimum functional requirements have been assumed, which have been split in following two berth development phases. Berth development phase 1: Vessel type: Loa = 105 m, B=16 m (1 nos) Berthing type: Side berthing Total length of Berth: 130 m Water depth at berth 7 m (under keel clearance to be approx. 2 m)

6 6 DEVELOPMENT OF NEW TIMBER TERMINAL Berth development phase 2: (deep-sea berth) Vessel types/configuration: Loa = 180 m, B=30 m (1 nos) or Loa = 105 m, B=16 m (2 nos) Berthing type: Side berthing Total length of Berth: 240 m Water depth at berth 12 m (under keel clearance to be approx. 2 m) It shall be noted that the vessel configuration for the Berth development phase 2 could be one large vessel (Loa =180 m) or two smaller vessels (2 x Loa = 105 m) The berth development is depending of the future export timber quantities (demand) and the investment plan. The shown phasing above is assessed to be an economical and technical feasible solution. Preparing the berth for 12m water depth in phase one would only increase the construction cost (CAPEX) without any direct benefit, because the large vessel could not operate optimal at the berth and additional mooring points would be required. Due to different bathymetric and geotechnical conditions at the locations it is recommended to carry out further analysis of the technical berth development (phasing) together with the investment plan for the selected location. At most locations the seabed is relative steep in front of the berth and the required dredging may not be an important cost driver. A typical berth structure consist of a suspended concrete deck supported on steel piles. If the berth structure in phase one also is designed for the final phase (12m water depth), the upgrade of the berth structure from phase one (130 m) could consist of installing an extended concrete deck another row of steel piles. 3.2 Navigational requirements Berthing area in front of the berth shall be dredged/excavated to secure berthing with or without tugboat. In the following, it is recommended that the dredging area in front of the berth to be 1.5 times length of longest vessel (Loa). The dredging width to be not less than 1.25 times max beam of largest vessel. Turning diameter for the vessel: 4 x Loa if vessel is manoeuvring without tugboats assistance and/or thrusters. The diameter could be reduced to 1.5 x Loa, if the vessel use main propeller and bow thruster.

7 DEVELOPMENT OF NEW TIMBER TERMINAL 7 Berth configuration summary: Berth development phase 1 Berth development phase 2 Max vessel dimension Loa= 105m, B =15 m Loa= 180 m, B =30 m Berth length 130 m 240 m Required water depth 7 m 12m Berthing area* (in front of berth) L = 140m, B =19 m L = 270 m, B = 38 m Turning basin D = 160 m D = 270 m *) Berthing area where required water depth is guaranteed 4 Location: Holmen and Gilhusbukta, Drammen Locations Holmen and Gilhusbukta are both situated in Port of Drammen and will be discussed in this chapter. (see Figure 5) Gilhusbukta Lierstranda (existing timber terminal) Holmen Figure 5: Location Holmen and Gilhusbukta and the existing timber terminal at Lierstranda

8 8 DEVELOPMENT OF NEW TIMBER TERMINAL 4.1 Approach The entry to Port of Drammen from the main navigational fairway in Oslo fjord is via Svelvik and Drammen Fjorden. Until Svelvik the navigation is considered to be fairly good, but at Svelvikstrommen the navigation is limited with a navigation channel approx. 100m wide and maximum water depth approx. 10 m. (see Figure 6). Ongoing maintenance dredging is necessary due to siltation in the channel. The channel is most often frozen every winter, but is kept open by icebreakers. Svelvik channel is marked with buoys. From Svelvik vessels enters Dramsfjorden with good navigation access up to Port of Drammen. Figure 6 Navigation channel at Svelvik (Svelvikstrommen) Within the Port of Drammen at Holmen and at Gilsbukta the manoeuvring conditions are considered to be good and protected. In front of the berths there is sufficient area for turning the vessels. A low water area west of Gilhusbukta reduces the berthing access (See Figure New berth - Holmen The island of Holmen lies at the mouth of the river Dramselva. As shown on the Figure 7 the harbour area will be extended according to the future port

9 DEVELOPMENT OF NEW TIMBER TERMINAL 9 development from Port of Drammen. The extension includes mainly land reclamation and construction of new berths. The fully developed timber terminal includes 240 m long new berth and water depth of 12 m, which can be achieved without much dredging in front of the berth. For a 12 m water depth at the berth there is a need for dredging of approx. 2 m at the Svelvik navigation channel extending the water depth in the channel to 12 m. Figure 7 Future development of Holmen in Drammen.(Source Port of Drammen) 4.3 New berth - Gilhusbukta The entire Gilhusbukta bay is expected to be reclaimed and used for storage of timber. The reclaimed area is almost of the same area size as the existing timber terminal at Lierstrande. The new berth can be installed in front of the reclaimed area. On Figure 5 is the berth located so that a minimum of dredging is necessary to reduce the cost.the width of the bay is approx. 500 m, which could be used to develop other business if berth is extended further. Otherwise, the existing marina could be relocated to the eastern part of the new reclaimed area. The typical berth structure could be a suspended concrete deck on supporting steel piles and an underlying inclined rock revetment. The extent of soft soil (mud) is not known, but the area could be filled with over height and then use the timber over time as preload. The timber storage area does not require a hard pavement, but have an approx. 0.5 m top layer of crushed rock. This could reduce the constructions cost for the reclamation, soil improvement and pavement. The fully development of the timber terminal includes 240 m new berth and water depth of 12 m, which can be adopted without much dredging in front of the berth. For a 12 m water depth at the berth there is a need for dredging of approx. 2 m at the Svelvik navigation channel extending the water depth in the channel to 12m.

10 10 DEVELOPMENT OF NEW TIMBER TERMINAL 5 Location: Storsand Sandtak, Hurum Storsand Sandtak consist of a small marina and an outer basin with small boats and a small export berth for sand and gravel (See Figure 8). The southern breakwater protect the small boats in the outer basin and partly the entrance to the inner harbour basin. 5.1 Approach The exiting port Storsand Sandtak is approached by de Oslo fjord. The approach is used by many vessels going to Port of Oslo. North of the position Filvet (navigation light) the Oslo fjord narrows considerably. Outside the port location the small reef Storskjær is located. The smaller vessels (Loa=105 m) should be able to access the port both north and south of the island Storskjær. The future larger vessels (Loa=180 m) should approach the port north of the island. Both the existing and future vessel will not be able to turn inside the outer basin in the exiting port due to (turning diameter 160 m/270 m). Storsand Strandtag Figure 8. Seachart with the Marina Storsand sandtak and the reef Storskjær to the right. 5.2 New berth - Storsand sandtak The average water depth in the outer basin varies from 3.5 m to 5.0 m and at the berth approx. 4 m. The small timber vessels (Loa=105 m and draft 4-5 m) would not be able to reuse the existing port, even if the exiting berth were extended. A new port layout for both existing and future vessels is necessary. The new berth could be partly placed in front of the small existing export berth, but with a reduced berth length of max 140 m, which means that only one smaller vessel will be able to berth (See Figure 9). It is assumed that the all

11 DEVELOPMENT OF NEW TIMBER TERMINAL 11 small boats in the outer basin are relocated as well. The southern reclaimed peninsular will secure good and protected berthing conditions for the new berth, but the manoeuvring towards the berth is difficult, due to the narrow space between the new berth and the southern breakwater. The vessel may berth both with stern to or bow in. It is expected that the vessel will not need any tug assistance. Alternatively, the berth could be placed at the outer entrance to the existing marina, but less protected and harder berthing conditions leading to down time at the berth. For this alternative, the berth could be fully developed to 240 m and with water depth of 12 m. The typical berth structure could be a suspended concrete deck on supporting steel piles and an underlying inclined rock revetment. Figure 9: Location: Storsand Sandtak The distance from the reef Storskjær to the berth is less than 350 m. 6 Location: Mulvika, Holmestrand The location Mulvika is located just south of Holmestrand. 6.1 Approach The location Mulvika is approached from Oslo fjord navigation fairway. The approach is also used by vessels going to Port of Drammen. The approach is considered to be straight forward until vessels reach South of Langøya. The navigation towards the new timber terminal would continue into the Holmestrandfjorden. After the vessel has passed Mulodden navigation light, the vessel shall turn 180 degrees and finally proceed towards the new berth. The manoeuvring is considered to be fairly good. In front of the berth, there is space enough for turning the vessel (160 m/270 m). The width of the bay is approx. 840 m (see Figure 10), which makes the manoeuvring conditions very good. Further, the berth is protected by the peninsular from waves and currents from south and west directions.

12 12 DEVELOPMENT OF NEW TIMBER TERMINAL Figure 10: Location Mulvika, Holmestrand (width of bay approx. 840 m. The new berth is shown, l=240m) 6.2 New berth Mulvika The new berth fully developed (240 m) to be developed in the extension of the existing grain terminal. The 10 m water depth line lies relatively close to the existing shoreline, which should reduce the amount of dredging work to secure 12 m water depth in front of the berth. The typical berth structure could be a suspended concrete deck on supporting steel piles and an underlying inclined rock revetment. 7 Summary of findings/conclusions The summary of the high end study of the four considered locations are listed in the following: Navigational access to all four location are considered to be fairly good, but it should be noted, that the navigational channel at Svelvikstrommen will be a constraint if very large vessels (laden draft >10-11 m) shall call the berth at Holmen and Gilhusbukta. The berthing and manoeuvring conditions at Holmen, Gilhusbukta and Mulvika are considered to be good at the developed berths and fairly protected from the natural surroundings. At Storsand Sandtak is the

13 DEVELOPMENT OF NEW TIMBER TERMINAL 13 berthing difficult, due to small reef Storskjær just outside the existing marina. If the new berth is located in line with the southern breakwater down time must be expected at the berth, because the berth will be unprotected from waves from the south direction. For all four locations is it possible to develop the timber terminal to a deepwater berth with 12 m water depth. As noticed above is the water depth at Svelvik navigation channel maybe a constraint for the location Holmen and Gilhusbukta. At Storsand Strandtak the berth development could have an impact on down time due to less protection of the berth. The phasing of the berth development is important in terms of construction costs (CAPEX). It is recommended when a location have been selected that further technical analysis is carried out in order to prepare a rough master plan for the berth layout and some conceptual design of the berth in order to optimise both phasing and investment.