Can digital technologies provide solutions to extend existing boundaries?

Modal shift is ultimately the result of a competitive advantage that one transport mode has over other transport alternatives. Besides price, flexibility or sustainability, the speed and reliability of a service are key factors to gain market shares. In this context, infrastructure bottlenecks such as locks, bridges with limited clearance or narrow fairways are often-cited obstacles that limit the potentials of modal shift towards inland waterways.

As adaptions of infrastructure come at a high cost, with potentially high environmental impacts, and may take decades to come into effect, digital technologies may provide means to reduce bottleneck effects by enabling better use of existing waterway capacity.

IWT infrastructure bottlenecks are obvious to find

From transport perspective, a term “bottleneck” is usually associated with capacity constraints within a transportation system. It is the very nature of infrastructure bottlenecks that they only limit the systems performance under certain conditions, e.g. when traffic exceeds the available capacity.

With that in mind, it is easy to identify infrastructure bottlenecks within the IWT system: Most obvious are locks with their limited space, varying service patterns and sometimes restricted opening times. Non-movable bridges with low clearance might restrict the height of a vessel and thus limit the amount of cargo that can be transported. This is especially crucial in container shipping, where bridges may decide whether an additional tier can be loaded or not. Another prominent example are narrow fairway sections that lead to difficult nautical conditions, accompanied by required speed reductions as well as passing restrictions.

Fully eliminating those bottlenecks is difficult without heavy infrastructure investments. However, the possibilities for improvement by simply upgrading or extending infrastructure are limited. First, upgrades on inland waterway infrastructure are cost-intensive, take a long time and its improvements will only be measurable in the long run. In addition, inland waterway constructions often come with huge environmental impacts. Hence, it is obviously not useful to maximize IWT capacities at all costs.

A major threat to modal shift

What exactly makes bottlenecks so obstructive to modal shift?

As stated in the beginning of this article, not just costs, but factors, such as speed and reliability, determine modal choice. As the impacts of infrastructure bottlenecks on specific trips are hard to predict, uncertainty becomes a significant element of transports on certain routes.

Evidence for the effects that infrastructure bottlenecks can have on IWT operations in a specific corridor can be found, for example, in the hinterland of Bremerhaven (Germany). Due to comparably short transport distances, IWT in this region is in strong competition with road transportation. Even though the River Weser – which connects Bremerhaven to important intermodal hubs such as Minden, Hannover and Brunswick – allows for the operation of 110m vessels, IWT operators are very reluctant to deploy those vessels in liner services due to uncertain travel times caused by a number of locks and fairway passages with encounter restrictions for larger vessels. One third of the Mittelweser stretch ranging from Bremen to Minden has been declared as no passing areas for this type of vessels. In this specific case, competitive cost advantages by exploiting the economies of scale in IWT are at risk and thus pose a major threat to a modal shift.  

IW-NET investigates the use of digital technologies to limit bottleneck effects

To assess the potentials of digital technologies in the quest to reduce the impacts of IWT infrastructure bottlenecks, a working group within the IW-NET consortium will investigate the effects of different measures to optimize traffic flow by means of simulation techniques.

The River Weser will serve as the application scenario to test and evaluate a set of different collaborative and intelligent traffic flow optimization strategies. This involves better use of available river information services, more specifically vessel tracking and tracing (VTT), as well as traffic situation forecasting that enables infrastructure managers to ease traffic flows.

IW-NET will take up the concepts developed in European initiatives, such as the RIS-Comex project and will contribute to the ongoing debate with an impact assessment that shall enable legislators to better understand how available infrastructure can be exploited to a greater extend through the use of digital services.

The discussion shows that an intact and reliable infrastructure is of critical importance to the success of modal shift initiatives and thus to the EU’s objective to decrease GHG emissions in the transport sector.

What should not be left unspoken: even if is possible to generate more transport volume through a successful modal shift, an increased amount of traffic is likely to uncover new bottlenecks, which might endanger previous gains.

The IW-NET project therefore provides the foresight that is needed for sustainable IWT growth.   

Arne Gehlhaar,
Patrick Specht

ISL – Institut für Seeverkehrswirtschaft und Logistik