How Climate Change Affects Transportation Systems - Part 3: Drought

This article is part of a series on the effects that climate change has on transportation systems.

Climate change causes more extreme fluctuations in the water cycle. Sometimes there is just too much water, which was the topic of last week’s article. This week, we cover the opposite effect: when there is too little water. Drought is the ultimate enemy of waterborne transport, not only on rivers, but also for ocean-going ships that plan to cross the Panama Canal.

Nothing’s Fine on the Rhine

The Rhine is one of the most important waterways in Germany. It connects Germany with other European countries and the North Sea. Via canals, it is also connected with the Danube and thus with the Black Sea. Every day, countless barges transport coal, oil, grain, building material, and even heavy machine parts. Many industries have settled along this vital artery and are thus dependent on the constant flow of goods and material.

This year has seen the worst drought on record along the Rhine, causing the water levels to reach an all-time low. The Rhine did not actually dry up, so ships could still pass. But they had to significantly reduce their draft to avoid running aground. This was only possible by reducing the total load the ships took on in harbours, up to one fifth of maximum capacity.¹

In order to supply industries along the Rhine, many German states temporarily lifted the ban on Sunday truck transport so that some goods could be transported by road instead. Also, the Deutsche Bahn chipped in and planned to reactivate some old cargo wagons to help out. Yet this can only be a drop on the proverbial hot stone. Both rail and road in Germany are already overloaded and cannot simply absorb that amount of additional traffic. And some parts, like the gas turbines that Siemens produces in Mühlheim an der Ruhr, just won’t fit on any truck.² Thus the dependency on water transport cannot simply be replaced by other means.

Luckily, the worst part of the current drought is now over, and water levels are rising again. But what can shippers and industries learn from this situation to prepare for the next time?

One lesson that companies like BASF took from the previous drought in 2018 was to increase their stockpiles. But that will only take you so far when droughts get longer as climate change progresses.

Another measure is to introduce new types of barges that have less draft and thus can carry more load when water levels are low. But these ships are more expensive to buy and to purchase, so they might not see widespread adoption soon. Also, this approach has limitations. When water levels drop even further, even these ships have to reduce their load eventually. They are shifting the limits, but they cannot completely remove them.³

With climate change continuing, industries along the Rhine, but also other major rivers worldwide, face tough choices. Shall they increase their storage capacity to withstand even extended droughts? Shall they invest in additional means of transportation, like new railway connections? Or shall they even relocate their plants?

In any case, there is no easy choice. Industries and supply chain planners will have to cope with it. Drought along rivers will lead to additional costs and delays for all goods that are transported on them, and this will be a factor that has to be taken into account for supply chains in the future.

Panama Canal Running Low

Not only barges, but also ocean-going ships can be affected by drought. The oceans are not going to dry up anytime near. Yet the Panama Canal feels the effect of an ongoing scarcity of rainfall. The canal is filled by artificial lakes, and these lakes currently have very low water levels. The effect is that from the beginning of September, the maximum number of ships allowed to pass each day will be reduced from 36 to 34 and then later even to 32. In a previous drought in 2023, the daily number of ships had to be reduced even down to 22, cutting the capacity almost by 50%!⁴

Shippers who still want to send their ships through the canal have to pay a hefty premium, or they have to find alternative routes. As for the Rhine, many turn to land transport, via truck or train through the US. As in Germany, these routes are already crowded. This drives up transport charges and can lead to price increases for goods that were not meant to pass the Panama Canal in the first place.⁵

To make more water available, the Canal Authorities plan to introduce new reservoirs like the Rio Indio reservoir project. But such projects take a long time to complete.

As we can see, ocean-going ships are also affected by droughts, adding to the other woes of shippers like the war in Iran.

From Bad To Worse: Secondary Effects

Scarcity of water affects shipping directly and has severe consequences for our supply chains. But there are also secondary effects of droughts that exacerbate the situation.

Low water levels in rivers directly affect power plants that use the water for cooling. During the recent drought in Europe, the only nuclear power plant in Hungary had to be shut down. Such a situation can lead to power shortages that not only affect households and industries, but also electric trains and vehicles, reducing the capacity of transport systems even further.

Furthermore, a reduced shipping capacity also means less capacity to transport oil and fuel, so less fuel might be available for the trucks and ships.

And if a vital means of transportation like waterborne transport is not available, the pressure on the remaining modes increases, leading to delays, increased costs, and breakdowns.

Now imagine that one or more of these factors come together in the case of a drought. This can lead to severe consequences, potentially leading to significant price increases or even shortages of vital goods like food, fuel, or building material.

Outlook

As I have shown in this article series, climate change has severe consequences for transportation systems and thus our supply chains. Heat, flood, and drought each have their own specific effects on our transport networks, both direct and secondary.

We can try to counter these effects by cooling our cities, reducing the sealing of the ground, and building ships with a lower draft. But every system has its limits, and every system might eventually fail. And as our transport systems are inherently complex with a lot of interactions within themselves and with other systems, they will very likely fail in unexpected ways.

The imperative thing to do now is to prevent climate change from progressing even further by reducing our greenhouse gas emissions quickly. We will likely not be able to control the consequences if we don’t.

Footnotes