Risk management in river basins

Emissions to air, water and soil and the number of accidents at industrial facilities due to shortcomings in accident prevention had taken on alarming proportions by the 1970s. UBA addressed the problem and in the years since then has formulated a comprehensive risk management strategy for international river basins.

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By the 1970s the scale of the side effects of post-war industrialisation were becoming increasingly evident. Emissions to air, water and soil and the number of accidents at industrial facilities had taken on alarming proportions.

One of the worst accidents occurred in 1976 in the small city of Seveso, Italy. The emissions of dioxins following an explosion at a trichlorophenol plant poisoned hundreds of residents. In reaction, Germany adopted the Major Accidents Ordinance in 1980, and the EU followed in 1982 with adoption of the so-called Seveso Directive to ensure that effective safety measures are established at high-risk facilities. 

Based on these historical events the focus of measures was placed on protection of the civilian population against the immediate effects of airborne emissions and the hazards of fire and explosions. The significance of environmental protection – and the protection of ground and surface water in particular – remained theoretical. This was to change after the Sandoz accident in 1986, which triggered massive fish die-off and severe damage to the aquatic ecosystem along the Rhine.

As a consequence, both the Major Accidents Ordinance and the Seveso Directive were amended to include aspects of possible impacts on bodies of water in accident prevention.

The International Commission for the Protection of the Rhine (ICPR) had already been committed to improving the water quality of the Rhine for several years. The shortcomings in accident prevention became the centre of focus after the Sandoz spill, and UBA seized this opportunity to then develop a comprehensive risk management strategy for international river basins.


Danger prevention management

Safety recommendations 

Working through the International Commission for the Protection of the Rhine (ICPR) UBA advanced the idea of increasing safety levels at installations by also improving the safety of individual key functional units (storage, handling, pipelines, etc.). In the following years technical safety recommendations for action were formulated for ten functional units, which the ICPR also recommended be implemented in the Member States. 

By 1999 accident-related water pollution in the Rhine river basin had declined by over 99% compared to the levels which were common in the 1970s and 1980s.

These successful approaches were transferred to the newly founded International Commission for the Protection of the Elbe (IKSE) in the early 1990s, then to the International Commission for the Protection of the Danube River (ICPDR) at the end of the 1990s, and the International Commission for the Protection of the Oder at the beginning of the millennium, and to the UNECE. In the meantime more than 30 international harmonised guides have been developed for various relevant functional areas, industries or specialised sectors of industry.

A further area of focus for UBA in recent years has been its collaboration on the UNECE Convention on Industrial Accidents and UNECE Water Convention. A Joint Expert Group to the two conventions, with central coordination by UBA, developed safety guidelines for "Pipeline Safety" (2006/7), for "Tailings Management Facilities" (2008/9) and Oil-Terminals”. The guidelines were approved by all UNECE member states. Following the 2010 red sludge accident in Hungary, the authorities in Hungary are revising the inspection guidelines based specifically on this Safety Guideline for Tailing Management Facilities (TMFs).

In the framework of Advisory Assistance Programmes in Ukraine, Armenia, Georgia and Kyrgyzstan in 2013-2022, a methodology for assessing TMFs was developed and checklists on this topic were created.

Also, an UBA advising assistance programme for transboundary risk management in the Danube delta jointly developed a safety guideline for oil terminals with the UNECE. And recently we`ve set up an international expert group under the auspices of the UNECE JEG, to develop safety guidelines for fire-water management and retention. The central measure which was still an outstanding dept as a consequence of the “Sandoz” accident in 1986.


Although the safety guidelines provide for a basic level of facility safety, the implementing authorities are still confronted with the problem of which real measures to apply to ensure this safety. This is why the German Environment Agency (UBA) started in 2000 to elaborate on the safety recommendations/guidelines and draw up checklists which - combined with a catalogue of measures - enable a concrete strategy for the implementation of the required safety level.

Checklists also provide an excellent basis for training programme instruction for inspectors. Such advisory assistance projects make it possible to provide a systematic overview of the safety concept, offering a uniform benchmark and helpful recommendations for potential clean-up action to countries within the UNECE region and all the way to China.

These checklists are now being further developed by China's Emergency Response Center in collaboration with Tsinghua University and the Environmental Monitoring Station of Jilin. The German checklist was taken as a starting point as was the classification of hazardous chemicals. In addition to water pollution, the Chinese checklist has taken up air pollution.


Crisis management

Our main activities in this area were implemented within the IKSE in the early 1990s. Whereas an international warning and alarm plan had already been established for the Rhine, its principles had to be harmonised for the Elbe River with the Czech Republic.

UBA therefore initially introduced an international warning and alarm plan for the Elbe based on the plan for the Rhine. A significant new element in the plan is the discreet alarm trigger levels which are based on amounts of emissions of substances hazardous to water. The corresponding water hazard was determined according to water risk classes (WRC) or the relation of these classes to risk phrases (R-phrases) under the European Chemicals Act. The differences in emissions of substances hazardous to water were shown in a simple matrix system way required even the UBA to rally behind it. It was then approved by the Commission for Hazardous Incidents (cf. Commission document Orientierungswerte für Störfallbeurteilungswerte bei Gewässerschäden). In the meantime its approach has been accepted not only by the Elbe Commission but also that of the Danube and Oder, as well as in a number of different watersheds in Eastern European and the Caucasus (Neman, Dnister, Kura).

The R-phrase relation of substances hazardous to water developed for the first time in the IKSE warning and alarm plan was further developed into a score system and resulted in the Administrative Regulation on Substances Hazardous to Water (VwVwS), which was then repealed with the entry into force of the Federal Ordinance on Facilities Handling Substances Hazardous to Water (AwSV) in 2017. In the meantime, this score system for R-phrases has been adapted to the new Global Harmonised System.

In turn, the matrix system developed in conjunction with the emission volumes made it possible to simply normalise and classify the water hazard potential of accidents and that of installations according to the so-called "Water Hazard Index" (GSI), or the meanwhile widespread "Water Risk Index" (WRI).

Water Risk Index (WRI)

The WRI corresponds to the logarithm to the base 10 of the WRC 3 substance quantity. This means that e.g. a substance quantity of 1000 tonnes (106 kg) of a WRC 3 substance corresponds to WRI = log 106 = 6.

For the evaluation of existing WRC 2, WRC 1 and WRC "0" substance quantities, these were normalised to WRC 3 substance equivalents. For reasons of simplification, this is done by a factor of 10 graduation.

In other words, WRC 2 substance quantities correspond to 10%, WRC 1 substance quantities to 1% and WRC "0" substance quantities to 0.1% of a comparable WRC 3 substance quantity. Based on a water input of 1000 kg of WRC "0", 1, 2 or 3 substances, this would lead to a WRI of 0.1, 2, or 3.

The International Commission for the Protection of the Danube River (ICPDR) applied the WRI for inventorying more than 600 installations exposed to flood risk. 

Map showing facilities on the Danube with water hazard potential
Inventory of facilities on the Danube with water hazard potential
Source: IKSD