Brief presented by Brian Slack to the Standing Senate Committee on Transport and Communications. February 26, 2024. This brief is based largely on a report I co-authored with Dr. Claude Comtois that was submitted to Transport Canada in September 2022: « Résilience des composantes d’infrastructures de transport et de logistique du Port de Montréal : compilation, analyse et options d’aide à la décision dans un contexte de changement climatique ». It is a study that sought to identify how changes in weather conditions brought about by climate change could affect the facilities and operations of the Port of Montreal.

It did not consider broader impacts of climate change, such as the need to decarbonise transport systems and infrastructures. Here, I provide a

summary of the methods and results. I go on to discuss one of the major issues drawn from the report: water levels in the St. Lawrence River channel It emerged as a challenge to infrastructures, operations and supply chains of the port.

Report Resume The impacts of climate change on the Port of Montreal were measured and assessed under three broad elements: port infrastructures (comprising maritime access, physical installations, and rail and road access), port operations (representing the means by which cargo is handled between shore and ship as well as storage), and the supply chains that embody the supply and distribution shipments passing through the port, particularly grain, containers and liquid bulk. A detailed inventory of these assets was undertaken, and a measure of their sensitivity to weather parameters evaluated.

Seven temperature indicators, seven precipitation indicators, and various values representing wind, storms, ice conditions and water levels were identified. The actual occurrence of these elements between and were measured. Consultants (Ouranos) provided two sets of predictions of climate changes to for each of the factors selected above. The model predictions are based on RCP4.5 and RCP8.5 values. It should be noted that the latest IPCC reports have settled on values between RCP 2.5 to RCP4.5, and has rejected RCP8.5.

Ouranos’s climate predictions provided the means to estimate changes in intensity and occurrence of the indicators. From these measures risks for each of the elements of infrastructure, operations and supply chains were calculated. Out of interactions 64% were identified as providing no change or were beneficial, 23% represented having some limited risk, 10% interactions represented undesirable risks to the port, and 3% indicated severe risks.

While indicating that the port of Montreal possesses important resilience to climate change, there are several components of infrastructures, operations and supply chains that require adaptations and mitigations. For infrastructures channel water depths, telephone and electricity networks, and drainage systems are revealed to be most vulnerable assets. Heat waves, intense periods of precipitation, and freeze–thaw conditions are revealed to be the most impactful elements. For operations, cargo handling activities are the most prone as a result of heat waves, high precipitation events, wind and ice storms.

For supply chains it is revealed that containers are most impacted by water level issues. It should be noted that while Ouranos was able to provide very precise predictions of future temperature and precipitation values, the level of detail of freezing rain and wind conditions was much less detailed. The issue of water depths at the Port of Montreal The water levels of the St. Lawrence River between Montreal and Quebec City have been a challenge ever since European settlement. Even shallow draft sailing vessels had difficulties because of shallows through Lac Saint-Pierre.

In the 1830s dredging began and a ship channel was opened up for commercial navigation. The channel has been progressively deepened to its present depth of 11.3 metres. Until the 1980s the channel was adequate for most shipping (the St. Lawrence Seaway is only 8.2 metres). Variations in water levels have been known for a long time. We traced the fluctuations from to 2019 (see Table). Dry periods are years when levels fell below the mean, and below chart datum refers when water levels fell below the published minimum water column depth.

T The results show that cyclical fluctuations in water levels have been present for a long time. There is some evidence that climate change may have resulted in the unusually long wet period from 1967-1997, and for the very severe dry period of 1988-2013. The challenge of low water is felt most by the container trade. Throughout the world ship sizes have been increasing, and the port’s major competitors on the US east Coast have been dredging channels to 15m.

During the severe years around the turn of the Twenty-First Century the shipping lines charged Montreal customers a surcharge of $200 per box, which led to competitive advantages for New York and Norfolk. It apparent from climate predictions of warmer temperatures along with anticipated return of low water cycles that the port of Montreal faces a future challenge. The issue is complicated, however. Water levels at Montreal depend very largely on discharge from Lake Ontario. This water has been controlled since at the Moses – Saunders dam at Morrisburg (NY).

The levels are regulated by the International Joint Commission (IJC), which requires water levels in Lake Ontario to be maintained, as well as the flow through the local hydro-electric power dam. It may be noted that while levels in Lake Ontario since have fluctuated, the challenging low water years at the port of Montreal have been much more severe.

A new set of regulations for water management by the IJC has been developed since that sought to address issues of wetland maintenance around Lake Ontario, but also offers the Port of Montreal the opportunity to request short term flushes of water to raise water levels in the port. It remains to be seen how effective these flushes during a long-term low water period are. DRY PERIODS YEARS BELOW CHART DATUM 1920-26 None 1930-44 1933, 1934, 1935, 1936, 1957-66 1960, 1962, 1963, 1964, 1965, 1998-2013 1998, 1999, 2000, 2001, 2002, 2003 2005, 2007, 2010, 2012.

In the report we reviewed the ways the Port of Montreal might adapt to low water. These included dredging, damming the river to raise water levels, real-time monitoring of water levels, and hydrological work in Lac Saint-Pierre. Costing the alternatives led to a recommendation of real time monitoring. The Port of Montreal and the Canadian Hydrographic Service have developed digital monitoring of the ship channel. This provides ship captains with the means to precisely measure how much cargo can be loaded on board before departure.

It is of no use to ships loading overseas since they may be more than one week away from arrival at Montreal, where the water levels may have changed substantially. Efforts to predict the levels of water have proved to be unreliable after 3-5 days. Other solutions are required. Brian Slack Ph.D. (McGill), Honorary Doctorate (university of Le Havre) Distinguished Professor Emeritus, Concordia University.