Scientific Content

The main purpose of the workshop was: (a) to provide an opportunity for increasing the awareness and providing an overview of the water and sanitation sector progress in risk management practiced in diverse conditions of the participating countries, and (b) to promote close co-operation among scientists from the participating countries. The overall goal of the program was to bring together scientists from NATO and Partner countries and focus their communications on challenges in water supply and sanitation systems impaired by operational failures, natural disasters and war conflicts. The workshop was focused on the issues surrounding emergency access to drinking water systems, wastewater and sanitation systems following operational failures, natural disasters and the impact of conflict. This was achieved by the ARW technical program containing paper and poster presentations, and extensive discussions. For practical reasons, the ARW program with 30 contributions was divided into four major sections: (a) Vulnerability of Wastewater and Sanitation Systems, (b) Vulnerability of Drinking Water Systems, (c) Emergency response plans, and (d) Case studies from regions affected by Drinking Water System, Wastewater and Sanitation System failures. The papers presented addressed a broad variety of issues corresponding to these four sessions and ranged from reviews and case studies to scientific papers. A synthesis of the presented papers follows.

The first two sessions dealt with Vulnerability of Wastewater, Storm Water and Drinking Water Systems. In the introductory paper, an overview of hazards, vulnerability and mitigation measures for both wastewater and drinking water systems was presented, and served as a starting point for the rest of the workshop program. Urban drainage was addressed in four papers. The paper from Belgrade elucidated the risk of flooding in dyke-protected areas by backflow through sewers. Such a risk could be reduced by effective backflow check valves. A paper from Bulgaria outlined a procedure for assessing risks and uncertainty in urban drainage networks, using a Fuzzy set approach in combination with a standard urban runoff model. Design problems encountered in the Pristina airport drainage project were analyzed and identified, including the use of questionable methodology and deficient input data. The last paper focused on risk of drainage failures due to unplanned development in a Serbian urban catchment, and proposed remedial measures.

A large block of papers addressed the issues of risk in drinking water infrastructures, starting with assessing the drinking water security and the development of municipal strategies for security enhancement in Canada and the USA, including the vulnerability assessment, and the development of emergency response plans. An overview of the water supply in Istanbul was presented. A number of challenges were identified including the lack of enforcement of source protection. Disinfection of drinking water by chlorine generates various by-products which impact on drinking waters, particularly where source water contains high concentrations of natural organic matter. A case study from Turkey was presented. On-line monitoring of water quality in drinking water systems is gaining on importance; at present, it focuses on monitoring surrogate parameters, which may trigger collection of samples for investigations of the second tier parameters of immediate importance. Groundwater modelling in a Ukrainian region was presented and used to assess the risk of source water contamination. Current problems with drinking water production in Chernivtsi (Ukraine) were presented. The main issues include overproduction, poor quality, system losses (leakage) and the resulting land slides. A case study of a drinking water aquifer restoration following a MTBE spill in Belgium was presented, and focused on a pump and treat approach. Steps to be taken in developing water safety plans were described, including such steps as a system assessment, effective operational monitoring, and proper management.

Wastewater management systems were addressed in four papers. The challenges faced by Slovak managers in charge of wastewater treatment were analyzed with respect to the goal of establishing full treatment in all municipalities by 2015. Another issue reported from Slovakia was wastewater reuse and reclamation. This alternative source of sub-potable water is gaining on significance in view of limited water resources. Radioactive effluents from an industrial zone in Ukraine with uranium processing were assessed with respect to potential impacts on receiving waters. Overall, the situation of dealing with radioactive waste is unsatisfactory. Sewer modelling in areas susceptible to land subsidence due to mining presents special challenges to the changes in nodal point elevations and the needs to account for such anomalies. Finally, an economics paper presented valorisation of the benefits of wastewater treatment, using the so-called “shadow pricing”. Finally, one paper presented risk of water contamination in coastal areas, examining the effects of currents transporting water in various directions.

Another source of risk in water supply and sewer networks is caused by aging infrastructure and the need for rehabilitation, as addressed in four papers. The first paper addressed the risk and vulnerability of the drinking water system in Bergen (Norway), and the way the system benefits from redundancy of raw water sources. Asset failure analysis can be conducted by using such models as the Evolutionary Polynomial Regression, which is superior to other comparable methods. The planning of rehabilitation activities can be done by using commercial software to develop a network reconstruction plan, rather than addressing individual pipes only. Finally, the costs of drinking water system leakage losses were assessed, and the systems with large leakage were found economically inefficient.

There were also six posters dealing with drinking water supply in Belarus, shortage of potable water in Kumanovo (Macedonia) during the war conflicts in 2000, and various aspects of wastewater treatment in the Czech Republic and Slovakia.