CABLE FERRY SERVICE BUCKLEY BAY AND DENMAN ISLAND WEST Feasibility Review. References. Executive Summary

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1 CABLE FERRY SERVICE BUCKLEY BAY AND DENMAN ISLAND WEST Feasibility Review PREPARED FOR: BC Ferries Victoria, British Columbia DOC: REV: FILE: BY: William L. Moon III, PE PROJECT NAVAL ARCHITECT CHECKED: Justin M. Morgan, PE PROJECT OCEAN ENGINEER APPROVED: David W. Larsen, PE PRINCIPAL-IN-CHARGE DATE: 8 February 2012 References 1. BC Ferries Buckley Bay and Denman Island West Terminals- Proposed Cable Ferry, Golder Associates Environmental Assessment, 18 January Fisheries and Oceans Canadian Environmental Assessment Act Screening Report, Path No. 09-HPAC-PA , CEAR No , DFO No Transport Canada Navigable Waters Protection Act approval for Ferry Cable located at Buckley Bay, File No ( ), 9 November Transport Canada Navigable Waters Protection Act approval for Ferry Terminal alterations located at Buckley Bay, File No (T4414), 4 November Transport Canada Navigable Waters Protection Act approval for Ferry Terminal alterations located on Denman Island (west terminal), File No (T4417.5), 4 November Executive Summary The Glosten Associates (Glosten) was tasked by BC Ferries to perform an independent review of the overall feasibility of a proposed cable ferry service between Buckley Bay and Denman Island at the present location of a conventional ferry (BC Ferries Route 21). Particulars of the design reviewed included: Number of Automobile Equivalents (AEQ): 50 automobiles. Total Number of People: 150 (passengers and crew). Length of Route: 1.9 kilometers. The review centered on the following topics: Assessment of operating environment. Analysis of ferry hull form. Cable modeling and dynamic analysis. Conceptual vessel design. Preliminary terminal design for both marine structures and uplands work. Environmental assessment and archaeological overview assessment. Risk assessment and crewing analysis. Review of existing cable ferry operations. Detailed business case. Cable Ferry Service 1 The Glosten Associates, Inc.

2 The documents reviewed are at the conceptual level for the various elements of the cable ferry operation. The existing design documents have been developed over several years by a range of companies focusing in their respective technical areas, which results in a moving picture for the overall design. Consequently, minor variations and inconsistencies among the various design elements were expected and not viewed as significant. As the design matures, the consistency and agreement between the various elements of the design is expected to converge. At 1.9 km, our research indicates that the proposed ferry service would be the longest cable ferry operation in the world by about 300 meters. The proposed cable ferry itself is large in size by cable ferry standards. When considering these two design elements together, it is clear that BC Ferries is advancing the current state of the art in cable ferry operations. As the design matures, a significant amount of additional engineering will be accomplished, and it is anticipated that all the various technical details and challenges will be resolved. From our technical review, there appears to be no insurmountable technical obstacles to the proposed cable ferry project at this point in time. Glosten believes that the business case presents a compelling reason to select a cable ferry for Route 21. The data presented by BC Ferries shows that a cable ferry is significantly less expensive from both an initial capital cost point of view and from an operational cost point of view. When these savings are combined, the business case shows that they more than offset the required capital cost to perform the modifications necessary at the two terminals to support a cable ferry. Reduced fuel consumption should result in the added benefit of reduced greenhouse gases. BC Ferries has an obligation to investigate alternate ways of providing ferry service for their ridership, with the goal of maintaining safe, reliable, and cost effective service while seeking to reduce upward pressure on fares. At the feasibility level, the documents reviewed support the decision to continue with the proposed cable ferry operation on Route 21 from both a technical and financial point of view. It is important to review the technical and financial elements at every stage of the project prior to embarking on the next stage, to ensure that the underlying fundamentals still support the project moving ahead. This feasibility review was an important step prior to embarking on the detailed engineering and design phase of the project. Operating Environment and Vessel Hull Form The design operating environmental data was reviewed and, in general, the work performed was suitable for conceptual design purposes and validated the decision to consider a cable ferry operation at this location. The various operating environment parameters were identified and a conceptual vessel size proposed. For concept design and feasibility level work, this represents a reasonable approach at a reasonable level of detail. Looking ahead to the next design development stage, it is recommended that the following measures be revisited to increase confidence in the selected values and data to be used in the design basis: Performance of a thorough statistical review of the wind/wave data and analyses in Baynes Sound to define a consistent set of design operating environment parameters for vessel operations. Cable Ferry Service 2 The Glosten Associates, Inc.

3 Expansion and correlation of data collection on site (including current measurements). Creation of a combined estimate of current due to wind-shear with the design tidal current. Definition of operability goals for the route. Clarification of how wind-generated waves and boat wake combine for design purposes. Investigation of other nearby sources of wind data for correlation and possible extrapolation of the short duration, on site measurement program. A limited set of model tests was performed for a smaller vessel of differing hull form on a nearby route in Lambert Channel (Route 22) experiencing more extreme wave conditions. These tests were informative for investigating cable ferry operations in an exposed location and resulted in BC Ferries concluding that a cable ferry was not suitable for Route 22. From these tests it was concluded that a larger vessel in the more benign conditions of Baynes Sound would be more appropriate for a cable ferry. Not having directly applicable model test results for Route 21 is not considered a shortcoming of the feasibility study; model tests are generally undertaken at preliminary design after further design definition. Using analytical methods and buoy data for determining vessel performance during concept design, as was done by BC Ferries, is a reasonable approach. It is recommended that a model test program be initiated in the next design phase to estimate vessel resistance, added resistance in waves, seakeeping behavior, and cable dynamics. Cable Modeling and Dynamic Analysis The cable modeling and dynamic analysis report provided by BC Ferries was reviewed and supports the feasibility of the cable ferry concept. No insurmountable technical challenges were identified in the report. As the design progresses, several aspects to consider include: A co-industry protocol has been established with the herring industry. The character of the fishing vessel fleet and anticipated set size and depth should be defined for further review of the minimum safe working distance. Expected vessel crossing traffic should be characterized and documented for design purposes and operational planning. It is noted that Transport Canada has approved the cable ferry concept with mitigation measures for vessel cross traffic (Reference 3). It is also noted that Route 21 does not cross a heavily transited channel, so this is a minor point. Added resistance in waves in the cable load estimates should be included. Updated design operating environment parameters should be incorporated into the cable analysis. The current and wave loads could increase from the values used in the reviewed analysis. An improved model of vessel wave loading and/or incorporate future model test results should be developed. Vessel environmental loads in docking case during extreme conditions should be included. Vessel momentum and impact in dock loads should be addressed. Once the final hull form has been determined, the basis of resistance margin should be defined, and future model test results should be incorporated into the vessel resistance estimate. Cable Ferry Service 3 The Glosten Associates, Inc.

4 Vessel Design Review Overall, the vessel design appears feasible. It is understood that the vessel design documents provided by BC Ferries are a snapshot in time. Moving forward, additional design work consistent with a traditional vessel design spiral will take place that potentially may alter the parameters defined in the concept design reviewed for this report. As such, only comments relevant to the feasibility of the vessel design are provided here, as well as comments significant enough to potentially affect the business case. Design and Construction Schedules. It is important to have realistic design and construction schedules for any project. The best estimates are based on information obtained by the prospective contractors. It is noted that BC Ferries has been interfacing with industry when establishing their schedules. At this point in the project, that is the most accurate schedule information available. Fuel Consumption. The fuel consumption of any vessel will have a large impact on the operating cost. The cable ferry concept will inherently have lower fuel consumption than a conventional propulsion system, because there is no propeller slip and no need to have main engines running to support both ends of the vessel simultaneously (geared diesel, double ended ferry). BC Ferries has estimated the combined fuel savings on both Routes 21 and 22 at about $100,000 per year. The fuel savings for the cable ferry on Route 21 are actually projected to be higher, but the business case conservatively recognizes the associated conventional ferry redeployment on Route 22 will actually have a modest increase in overall fuel consumption on that route negating part of the cable ferry s fuel savings. BC Ferries has not decided how to power the traction winch. As the design progresses, this project represents a good opportunity to re-explore alternative systems for powering the cable ferry. Lower fuel consumption should also result in lower greenhouse gas emissions. Vessel Arrangements. The arrangements of a cable ferry will result in a vessel that is less costly to build and maintain, as well as potentially be safer for the crew. The propulsion machinery requires considerably less space than a conventional ferry and is able to be located above the main deck. This will improve access to machinery for maintenance and will also result in no crew being stationed below the main deck, which is safer. Weight Estimate. Accurate weight estimates with appropriate margins are a vital element in naval architecture. At each stage of the design, a weight estimate of sufficient detail to match the design stage should be developed and should include the weight, longitudinal center of gravity, and vertical center of gravity. Design margins appropriate for the design stage should be included in the calculations. Skegs. Many vessels are fitted with skegs to provide directional stability. Skegs fitted to both ends of a vessel will not enhance its directional stability, however, but will add to the vessel s resistance and increase the fuel consumption. Considering cable ferry operations, skegs present additional underwater lateral area that potentially increases the loading on the cables. The decision to install skegs should be validated via analytical methods and/or model testing to weigh their potential benefits against their added resistance. Terminal Design Review The documents provided by BC Ferries regarding terminal design have been reviewed. Several different terminal design options were investigated prior to arrival at the selected option. The BC Ferries terminal concept uses overwater docks in lieu of the more typical Cable Ferry Service 4 The Glosten Associates, Inc.

5 beach/ramp configurations of other cable/chain ferry operations. This concept should prove advantageous for the high tidal range and with less environmental impact. The design documents outline a clear vision for the terminals and support the decision to pursue a cable ferry concept. As the design moves forward, a number of additional details will need to be developed: The interface between the cables and the docked ferry needs to be developed. Provision for and a clear representation of passengers on foot and/or being met by, bus, taxi, private car, etc., should be included in future work. Provisions for bicycles should also be addressed in future work. We understand the existing upland constraints place limitations on the amount of upland work that will be allowed to support this operation. Consequently, the proposed two lane ramps will improve vehicle loading times, but will be less beneficial during unloading operations, since the terminals exit to a single lane road on either side of the route. The two lane ramps will be a future benefit should traffic improvements be made to the roads on either side of the route. Environmental Assessment and Archaeological Overview Assessment BC Ferries has developed, submitted, and received approval for an Environmental Assessment (EA) for modifications to the Buckley Bay and Denman Island ferry terminals and the new construction to support the proposed cable ferry service (see References 1 and 2). The EA is comprehensive. Close attention is paid to inventorying vegetation, fish, migratory birds, and marine mammals in the near shore, coastal, intertidal, sub-tidal, and seabed zones. Responsible mitigation measures are recommended. The on-site Environmental Manager (EM) will provide additional protection in construction. The EA was reviewed by: 1. Fisheries and Oceans Canada (Reference 2). 2. Transport Canada (References 3, 4 and 5). 3. Environment Canada. The review from Fisheries and Oceans Canada has resulted in the Canadian Environmental Assessment Act Screening Report (Reference 2), which concluded that the Project is not likely to cause significant environmental effects provided the noted mitigation measures are implemented. Review of the cable ferry concept from Transport Canada, under the Navigable Waters Protection Act (Reference 3), concluded that the proposed placement of a cable to operate a ferry between Vancouver Island and Denman Island has not identified any impacts to navigation that cannot be mitigated... Similarly, the Transport Canada review of the two proposed cable ferry terminals (References 4 and 5) concluded that the altered terminals will not increase the interference with navigation. At the feasibility and concept design level, it appears the required EA steps have been considered and the necessary regulatory approvals obtained to continue moving forward with the project. As the terminal and vessel designs mature and the construction process moves forward, it will be important to ensure that the noted mitigation measures are included in the specifications, cost estimate, and business plan. Cable Ferry Service 5 The Glosten Associates, Inc.

6 Risk Assessment and Crewing Analysis BC Ferries has estimated that the minimum safe manning for the cable ferry is a crew of three (3) persons for a vessel with a total capacity of 150 people. The supporting information from BC Ferries included both operational studies by licensed ship operators and class society risk analyses. These studies identified and included assessments related to both design and operational aspects of the cable ferry operation. Standard manning requirements from Transport Canada (TC) do not apply to cable ferries, so BC Ferries extrapolated the standard TC manning requirements to a cable ferry (i.e., minimal propulsion system so, therefore, minimal engineering watch crew) as an initial assessment of the appropriate manning level. Subsequently, BC Ferries looked at manning from both the basic ship operational level as well as potential emergency operational levels for the various shipboard emergency scenarios. Both sets of analyses support a crew of three (3) for the cable ferry. Glosten has experience with small conventional car/passenger ferries (up to 149 people) with crews as small as two (2) people that have operated safely for many years; therefore, a crew of three (3) is reasonable. BC Ferries expects the cable ferry operation to have no impact on the expected levels of terminal staff. At the feasibility and concept design level, it appears that the appropriate risk assessment and crewing considerations have been considered and that a crew of three (3) is reasonable. Existing Cable Ferry Review Glosten conducted a search of existing cable ferry operations to determine the comparability of the proposed Denman Island route to existing cable ferry operations throughout the world. Both cable and chain ferries were considered in the review. A list of the relevant findings are included in Appendix A and briefly summarized below: Many cable ferries are employed throughout the world, ranging in size from 1 AEQ to 75 AEQ vessels. Maximum crossing distances are up to 1600 meters. Routes include both fresh water and salt water crossings. There is at least one chain ferry service operating in Europe that is larger in vessel length and car capacity than the proposed Denman Island ferry. This is the Torpoint Ferry in the UK, which connects Devonport in Plymouth with Torpoint in Cornwall. This service actually consists of three similar 73 AEQ ferries in parallel operation on parallel chains. The longest existing cable ferry crossing distance Glosten identified is approximately 1600 meters, which is 300 meters shorter than the proposed Denman Island ferry. This is the Keistio Finland ferry, which is located in the archipelago of Finland. The ferry route is fairly well protected, with only a short fetch for waves to develop. The Riverhurst ferry in Saskatchewan Canada has a slightly shorter 1500 meter crossing distance, but the exposure to waves is greater, with a fetch distance more closely resembling (but still less than) the Denman Island ferry crossing. Cable and chain ferries operate in both fresh water and salt water. Both the largest cable ferries and the longest cable ferry route identified in this report are in salt water service. From our research, Finland has a large fleet of cable ferries operating in salt water service, with some vessels even operating in seasonal ice laden waters. Cable Ferry Service 6 The Glosten Associates, Inc.

7 While the search verified that the Denman Island cable ferry would likely be the longest route in the world, the search did not identify anything insurmountable in the proposed Denman Island cable ferry service. The use of cables in salt water service for critical applications is routine and extends beyond cable ferries to include mooring systems for a variety of applications from floating bridges to oil drilling platforms. Due to the proposed crossing length, a detailed cable analysis should be conducted to validate the feasibility of the design as the project moves forward. Detailed Business Case BC Ferries has developed a comprehensive business case for adding the cable ferry to their current operation and redeploying the existing conventional ferry (M/V Quinitsa) displaced by the new cable ferry. This redeployment has a trickledown effect on other vessels within BC Ferries (and results in the proposed retirement of one ferry, M/V Tenaka), all of which are accounted for and considered in the business case. This business case includes the Net Present Value (NPV) of both capital costs and operating costs. Costs considered in the NPV analysis include: The cost to procure the cable ferry. The cost to modify the ferry terminal at Buckley Bay to allow the cable ferry to dock. The cost to modify the ferry terminal at Denman Island (West) to allow the cable ferry to dock. Revisions to previously considered capital cost expenditures for other vessels and terminals as a result of acquiring the cable ferry (i.e., vessel redeployments, refurbishments, and retirements). The operational cost savings for the cable ferry compared to the existing selfpropelled ferry; e.g., fuel, manning, and refit/maintenance. The business case presents a compelling reason to select a cable ferry for Route 21. The data presented by BC Ferries shows that a cable ferry is significantly less expensive from both an initial capital cost point of view and from an operational cost point of view, when compared to a conventional ferry. BC ferries has estimated the capital cost of the cable ferry and the Tenaka replacement vessel cost, based on initial shipyard estimates and extrapolation of costs from previous projects. At this point in the design process these estimates are reasonable. The capital cost is less than a conventional ferry, because the cable drive system is significantly less expensive than conventional propulsion machinery. The operational costs are reduced because manning is lower, fuel consumption is expected to be less, and maintenance costs are expected to be lower. When these savings are combined, the business case shows they more than offset the required capital cost to perform the modifications necessary at the two terminals to support a cable ferry. At the feasibility and concept design level, the appropriate elements have been considered in the business case. The findings and expected benefits of a cable ferry appear reasonable. Review of additional underlying details supporting the business case were beyond the scope of this report (i.e., review of individual cost estimates for each of the various elements of the business case) but, overall, the data reviewed looks reasonable and the findings economically sound. As noted above, BC Ferries has made a series of vessel redeployments and terminal upgrade assumptions in the current business case that support the economic case for a new cable ferry. This allows BC Ferries to avoid having to acquire a new conventionally powered ferry with Cable Ferry Service 7 The Glosten Associates, Inc.

8 its higher capital cost and higher operating cost. Should these assumptions change as the design process moves forward, the case itself may need to be updated as well. Conclusion The information reviewed by Glosten presents a compelling reason to select a cable ferry for Route 21. The data presented by BC Ferries shows that a cable ferry has the potential to reduce costs while maintaining safe and reliable service. The information reviewed supports the decision by BC Ferries to continue with the cable ferry concept and embark on the detailed engineering phase of the project. Cable Ferry Service 8 The Glosten Associates, Inc.

9 Appendix A Findings Route Location Crossing Length (m) Vessel Length (m) Car Capacity SW/FW Denman Island Route 21 BC, Canada SW Riverhurst Ferry, Lk. Diefenbaker SK, Canada FW Needles Ferry BC, Canada FW Raymond Island Australia SW Alassalmi Finland FW Arvinsalmi Finland FW Bergo Finland SW Hanhivirta Finland FW Hirvisalmi Finland FW Keistio Finland SW Kokkila Finland FW Puutossalmi Finland FW Skaldo Finland FW Tappuvirta Finland FW Vano Finland SW Vartsala Finland SW Cowes Ferry Isle of Wight, UK ~ SW Dartmouth Higher Devon, UK ~ SW King Harry Ferry Cornwall, UK FW Poole Harbor Dorset, UK SW Torpoint Devon, UK SW Cable Ferry Service 9 The Glosten Associates, Inc.