Attachment 9.1 TMEP Vessel Wake Assessment PRODUCED FOR TRANS MOUNTAIN PIPELINE ULC OCTOBER 29, 2018 Attachment 9.1 Attachment 9.1 TMEP Vessel Wake Assessment | Trans Mountain Pipeline ULC Revision 0 | October 29, 2018 Table of Contents Document Verification .................................................................................................................................................. i Disclaimer .................................................................................................................................................................... iv Executive Summary ..................................................................................................................................................... 1 1. Introduction, Purpose and Scope ................................................................................................................... 3 1.1. Introduction ......................................................................................................................................................... 3 1.2. Purpose .............................................................................................................................................................. 3 1.3. Scope of Work .................................................................................................................................................... 3 2. Regional Setting for Vessel Wakes ................................................................................................................. 5 2.1. Vessel Routes ..................................................................................................................................................... 5 2.2. Regional Vessel Traffic ....................................................................................................................................... 5 2.3. Regional Waves and Wakes ............................................................................................................................... 8 3. Vessel Wake Analytical Methods .................................................................................................................. 10 3.1. Kriebel and Seelig Method ................................................................................................................................ 11 3.2. Maynord Method ............................................................................................................................................... 12 3.3. Fourier-Kochin Integration Method ................................................................................................................... 13 3.4. The Froude Number ......................................................................................................................................... 13 4. Wake Predictions ............................................................................................................................................ 16 4.1. Project Defined Scenarios ................................................................................................................................ 16 4.1.1. Vessel Particulars ............................................................................................................................................. 17 4.2. Local Ferries ..................................................................................................................................................... 18 4.3. Comparison with Ambient Wind-Wave Conditions............................................................................................ 19 5. Project Wake Calculations ............................................................................................................................. 25 5.1. Vancouver Harbour ........................................................................................................................................... 25 5.2. Strait of Georgia ................................................................................................................................................ 28 5.3. Haro Strait ......................................................................................................................................................... 33 5.4. Strait of Juan de Fuca ....................................................................................................................................... 36 6. Discussion of Wake Effects ........................................................................................................................... 38 6.1. Effects on Commercial Shipping ....................................................................................................................... 40 6.2. Effects on Recreational Craft ............................................................................................................................ 40 6.3. Anecdotal Experience ....................................................................................................................................... 42 7. Conclusions .................................................................................................................................................... 44 8. References ...................................................................................................................................................... 45 List of Figures Figure 2-1: TMEP Vessel Routes .................................................................................................................................. 6 Figure 2-2: Regional commercial vessel traffic routes [Ref e] ........................................................................................ 7 Figure 2-3: TMEP Vessel Routes and Passenger/vehicle Ferry Routes ........................................................................ 7 Figure 2-4: Comparison of Projected TMEP traffic to existing (2018) regional traffic ..................................................... 9 Figure 3-1: Vessel wake pattern (adaopted from Schierech, 2001). ............................................................................ 10 Attachment 9.1 Creative People, Practical Solutions.® Page ii TMEP Vessel Wake Assessment | Trans Mountain Pipeline ULC Revision 0 | October 29, 2018 Figure 3-2: Example subcritical and supercritical wake ............................................................................................... 14 Figure 4-1: Locations of recorded regional wind and wave Data (From Ref f) ............................................................. 22 Figure 4-2: NOAA wave records, Juan de Fuca Strait (New Dungeness, OCT-MAR). (Ref f) ..................................... 23 Figure 4-3: Environment Canada wave records, Strait of Georgia (Halibut Bank, Apr-Sep) [Ref. f] ............................ 24 Figure 5-1: Computed Vessel Wake for Aframax Tanker and Escort Tugs – Vancouver Harbour............................... 26 Figure 5-2: Example Vessel Wake Patterns from Bulk Carrier and Power Boats ........................................................ 27 Figure 5-3: Vancouver Harbour – Comparison of Vessel Wakes with Ambient Wave Climate .................................... 28 Figure 5-4: Computed Vessel Wake for Aframax Tanker and Escort Tug ................................................................... 29 Figure 5-5: Example wake pattern from BC Ferry inbound to Tsawwassen ................................................................ 30 Figure 5-6: Comparison of Vessel Wake for Aframax Tanker and Escort Tug with BC Ferry ...................................... 31 Figure 5-7: Comparison of Vessel Wake for Aframax Tanker and Escort Tug with BC Ferry ...................................... 32 Figure 5-8: Strait of Georgia – Comparison of Vessel Wakes with Ambient Wave Climate ......................................... 33 Figure 5-9: Computed Vessel Wake for Aframax Tanker and Escort Tug ................................................................... 34 Figure 5-10: Comparison of Vessel Wake from Aframax Tanker and Tug with WSDOT Ferry .................................... 35 Figure 5-11: Haro Strait – Comparison of Vessel Wakes with Ambient Wave Climate ................................................ 36 Figure 5-12: Computed Vessel Wake for Aframax Tanker and Escort Tug ................................................................. 37 Figure 5-13: Strait of Juan de Fuca – Comparison of Vessel Wakes with Ambient Wave Climate .............................. 37 Figure 6-1: Aframax tanker with two escort tugs near Second Narrows, 2018-10-10 .................................................. 39 Figure 6-2: Aframax tanker with tug heading to Westridge Marine Terminal, 2018-10-10 ........................................... 39 List of Tables Table 3-1: Froude Number as a Function of Vessel Speed and Waterline Length ...................................................... 14 Table 4-1: Project Defined Scenarios. ......................................................................................................................... 16 Table 4-2: Aframax Vessel Data .................................................................................................................................. 17 Table 4-3: Tug Data ..................................................................................................................................................... 17 Table 4-4: Particulars