Just noticed they installed those new navigation sector lights on the Lions Gate Bridge. If you are out of line with the channel the light colour changes.
a) Vertical Clearances
Vertical clearances are given as distances measured from higher high water, large tide datum
(+5m) to the lowest member of the bridge structure, in way of the navigation channel.
Due to the curvature of the First Narrows Lions Gate Bridge, the maximum air draft for transit of
TCZ-1 is subject to the moulded breadth of the vessel, actual tidal height, air temperature,
bridge traffic load and the requirement for a minimum safe overhead clearance of 2m.
Reference should be made to Appendix A, First Narrows – Minimum channel depths and
maximum vessel air drafts based on TCZ-1 moulded breadth factor for channel width.
Vessels that exceed the maximum vessel air draft at higher high water may be able to transit
subject to tidal windows. Lower tides will increase the maximum allowable air draft but will
correspondingly decrease the available depth. The maximum tidal range is 5m.
Vessels with an air draft in excess of the maximum air draft allowed for transiting TCZ-1, which
require tidal windows as listed above, must obtain port authority and PPA approvals to transit
TCZ-1. The maximum air draft of the ship or floating equipment needs to be reported at least 24
hours in advance of transit to the port authority Operations Centre
([email protected]) and PPA ([email protected]).
PORT INFORMATION GUIDE – Source: Vancouver Fraser Port Authority – May 2018 62
The air draft must be verified by a qualified and independent local survey company within port
authority jurisdiction prior to transit. The detailed results of this air draft survey must be provided
to both the port authority and PPA. Thereafter, the verified vessel’s draft/air draft must be
maintained until completion of the transit.
Upon receipt by the port authority of the air draft survey, the port authority will review the transit
request and determine if the vessel is approved to transit the TCZ-1 with tide restriction.
Upon receipt of the air draft survey by PPA, PPA will liaise with the BCCP to verify actual transit
times based on current windows, tide height, vessel draft, air draft and other planned TCZ-1
vessel traffic. PPA/BCCP will validate the transit request and indicate to the dispatched pilot that
the air draft has been verified.
Transit windows are calculated using the static air draft i.e. the air draft of the vessel when not
moving through the water.
For air draft considerations, the center of the bridge is also the center of the navigation channel.
From Twitter they have to do an air draft survey before they can bring the ship under the bridge.
And for vessels like container ships that are offloading cargo and not taking on much (or any) for the return trip, they have to ensure that the vessel will still have adequate clearance sailing out of the harbour when it's riding higher in the water.
They still haven't moved it yet. Two tugs from Saam seem to be headed out that way. SST Grizzly is almost at the ship and SST Salish is just leaving the harbour now.
Port Authority boat is hanging around the bridge now.
Last edited by jollyburger; Sep 10, 2021 at 9:37 PM.
At the 4 minute mark it's under the bridge. My thoughts when viewing the video... 'Tugboat operator must be a great job'
Some people who are not familiar with the Lower Mainland would mistakenly think the skyline behind the Port as being Vancouver City.
Video is from 2:52pm to 3:53pm
At the 4 minute mark it's under the bridge. My thoughts when viewing the video... 'Tugboat operator must be a great job'
Some people who are not familiar with the Lower Mainland would mistakenly think the skyline behind the Port as being Vancouver City.
Video is from 2:52pm to 3:53pm
Prev
It’s just coming into frame now.
Linear Mode
