2018 PIANC World Congress – Panama
Presentation Topic: Inland Navigation/Locks/Infrastructure Design
Title: Navigation Improvements for the Welland Canal
Presenter: William R. Miles, PE, PEng
U. S. Waterways Principal
Bergmann Associates
Abstract
The St. Lawrence Seaway Management Corporation (SLSMC) has recently completed two improvement projects for the Niagara Region of the St. Lawrence Seaway System on the Welland Canal in Ontario, Canada. Approximately $120M CAD has been spent on these facilities to improve transport for Seaway vessels and safety for ship and Seaway operations staff.
There are eight (8) locks and five (5) reaches in the Welland Canal, and three (3) of those locks are twinned for simultaneous passage. The canal runs from Lake Ontario in the north to Lake Erie in the south, and the modern canal was built in the 1930’s with additional amendments constructed in the 1950s and 1960’s. In addition to the eleven (11) lock chambers there are concrete approach walls and timber tie-up (open quay) walls as part of the navigation system.
The main purpose for the tie-up walls is to allow for vessels sliding into position for entrance and exit from the locks. Other functions include provisions for vessels to tie-up for traffic control through the locks, mooring during bad weather, ship maintenance or inspection and access for service vehicles. Mooring has been accomplished using ropes tied to bollards and winches.
The Welland Canal is regularly closed during the winter Non-Navigation Season each year, typically between the dates of January 1st to March 20th, although closure and opening times may fluctuate depending on vessel traffic. During the Non-Navigation Season, some of the canal reaches may be dewatered to facilitate construction, inspection and maintenance of marine infrastructure, including the quay walls. The year-to-year schedule for the dewatering of specific reaches is established by the SLSMC based on requirements and priorities.
During a closure period in 2010, a partial collapse of a portion of the quay wall at Lower Lock 2 initiated a four year repair program that was contracted yearly by the SLSMC. Due to the deterioration of the tie-up walls a more aggressive 4-year replacement program was then contracted for design to the Bergmann Associates Team, which also included Moffatt & Nichol, Ellis Engineering, Quartek Group and Terraprobe as subconsultants.
The scope of this new program included the removal and replacement of four (4) reaches of the open-quay walls totaling 1.88 km during the non-navigation seasons of 2014 – 2017. The design was completed in August of 2013 and the project, with all four wall replacements, was tendered later that month.
Over the next four (4) navigation closure periods (January 1 thru March 20) one reach of roughly 500 meters of wall was replaced with more modern steel and concrete structures using prefabricated sections and creating more resilient structures. The last of the wall replacements was constructed in early 2017, and the renewed docking system is now in operation.
This project was initially documented at the 2014 PIANC World Congress in San Francisco, USA for work through design and the construction period for the first segment of wall that previous season. This paper will include updates and lessons learned from the next three (3) construction seasons, as well as a summary of the project success story.
The second modernization project was also begun in roughly the same period by the SLSMC, and included the installation of a hands-free mooring (HFM) system within the lock chambers on the Welland Canal, as well as in locks in other sections of the St. Lawrence Seaway System. Following the design and installation of a system by the SLSMC in Lock 3 in 2013 and 2014, the balance of the HFM system design was contracted to the Bergmann Associates Team in 2014.
Concurrent with the reconstruction of the tie-up walls in the Niagara Region of the canal, a new hands-free mooring (HFM) system was designed and installed within 9 of the lock chambers on the Canal also by the Bergmann Associates’ Consulting Team. The HFM system installed is manufactured and supplied by Cavotec Moor Master Limited, Kaiapoi, New Zealand. The purpose of the vacuum suction-type system is to make mooring inside the lock chambers easier for the vessel and safer for the deck line-handlers, since no lines would be necessary.
In order to install the HFM system in a lock chamber, slots at 3 locations that are roughly 15’-9” wide by 5’-8” deep by 65’ to 72’ high in dimension, with rails installed vertically in each side of the slots were installed in each lock. In the 2015 closure period the HFM system was installed in Locks 1, 2 and 7. In the 2016 closure period, the HFM systems were installed in the western lock chambers of the flight Locks 4, 5 and 6; followed in 2017 by installation in the eastern lock chambers. Each lock installation cost in the range of $2.4M - $2.8M CAD for single locks to $3.8 - $3.9M CAD for each twin lock, excluding the Cavotec unit and controls which were purchased by the SLSMC under separate contracts.
The presentation will provide some of the basic design details, analysis methods, system information, and lessons learned for both the tie-up walls and hands-free mooring system projects. Photographs of existing facility demolitions, new construction and finished projects will be provided throughout the presentation as well.