VE-I-1 + 2: Flood closures and low water restrictions on the Rhine
2019 Monitoring Report on the German Strategy for Adaptation to Climate Change
Table of Contents
VE-I-1: High-water closures to shipping on the Rhine
Over the past 30 years high-water closures have affected Rhine shipping, especially on the Upper Rhine. In 1999 and 2016 inland shipping was unable to navigate the Rhine for an extended period due to high water.
The graph shows in the time series from 1970 to 2016 the number of days with closures of Rhine navigation due to high water (exceeding of HSW at selected guide gauges). The graph is differentiated for the Upper Rhine (Maxau), the Middle Rhine (Kaub) and the Lower Rhine (Ruhrort). There is no significant trend for any of the three river sections. The values fluctuate significantly between the years. The highest value was reached on the Upper Rhine in 1999 with just under 34 days. The closures are rarest on the Lower Rhine.
VE-I-2: Low-water restrictions to shipping on the Rhine
Prolonged low-water phases have repeatedly placed incisive restrictions on shipping in the Upper, Middle and Lower Rhine sections. This was usually caused by summer drought and heat. In some cases, the impacts lasted well into December.
The graph shows the number of days from 1997 to 2017 on which the equivalent water level or the required fairway depth was reached or not reached. The graph is differentiated for the Upper Rhine (Maxau), the Middle Rhine (Kaub) and the Lower Rhine (Ruhrort). There is no significant trend for any of the three river sections. The values fluctuate significantly between the years. When low water restrictions occur, all three Rhine sections are usually affected, although the sections can be affected to varying degrees. The highest value occurred in 2003 with 47 days on the Lower Rhine.
High and low water levels – problems for shipping on the Rhine
In meteorological terms, 2018 was an extraordinary year which demonstrated how dependent Rhine navigation is on the weather and prevailing weather patterns. Great amounts of precipitation fell in the mild month of January, especially as rain, making streams and rivers swell. The Rhine’s water levels exceeded the relevant floodwater marks so that shipping had to be suspended temporarily on all sections of the river. As the year progressed, temperatures remained high and precipitation largely failed to materialise. On the Rhine, this led to an unusually long low-water phase in late summer and autumn which was associated with draught restrictions being imposed on inland shipping. As far as consumers were concerned, they had first-hand experience of these impacts in terms of rising petrol prices. As it was no longer possible for tank barges to navigate the Rhine owing to the maximum permissible draught and because, at around the same time, a major fire put a Bavarian refinery temporarily out of operation, petrol became rather scarce and expensive at filling stations in the south of Germany. In 2018, the total freight carried by Germany’s inland vessels was down by 25 million tonnes compared to the previous year, representing a decline by 11.1 %.
The Rhine is Germany’s most important inland waterway. The river enables cost-effective and environmentally sound transport of goods, facilitates imports and exports via North Sea ports in Belgium and the Netherlands, and it links important industrial centres within Germany.55 More than 80 % of goods transported by Germany’s inland shipping are conveyed via the Rhine. Whenever high and especially low water levels lead to restrictions imposed on Rhine shipping , this can entail – in some cases considerable – impacts on individual companies or complete production and delivery chains. Such impacts can range from increased transport costs to production losses in companies operating just-in-time production.
The rules governing Rhine shipping are contained in the pertinent police regulation (Rheinschifffahrtspolizeiver ordnung). According to this regulation, ships will have to reduce their speed and must be equipped with a radio telephone installation in cases where the water level exceeds the high-water mark I. In cases where the highest navigation level (HSW) is exceeded, the sections affected will be closed to shipping.
In the past, there have repeatedly been extended closures which were particularly incisive in the late winter and early spring of 1999 when the Upper Rhine was closed to shipping for several weeks owing to two high-water events. Latterly there were extensive closures on the Upper Rhine in June 2016 owing to persistent and heavy rainfalls. On the Middle and Lower Rhine, there were brief closures, above all in 2001, 2003, 2011 and 2013 although it was possible to rescind those in most cases after less than a week . So far no significant trends regarding high-water closures have been discerned for the Rhine.
In cases where water levels fall below a threshold set for a specific section of the river – on the Rhine if the water surface is level with the mark – shipping is usually still permitted. However, in that case navigation is subject to restrictions which depend on the specific draught of inland ships. On the Rhine such low-water phases usually occur in late summer from August until October. However, there has been an increase in the frequency of low-water phases lasting well into November or December. This is true for 2011, 2015 and latterly 2018. It was not possible, however, to discern any statistically significant trends.
55 - Unterrichtung durch die Bundesregierung, Bericht zur Risikoanalyse im Bevölkerungsschutz 2018, Risikoanalyse Dürre.
https://dserver.bundestag.de/btd/19/095/1909521.pdf
Objectives
Narrowing the bandwidth of uncertainties regarding the development of the availability of water and deducing tangible impacts on the infrastructure of waterways and shipping (DAS, ch. 3.2.11)
Avoiding the development of high water levels by adequate provision of decentralised opportunities in the entire catchment area of rivers for precipitation to seep away (DAS, ch. 3.2.1)
