Evaluation of risk assessments for source water protection areas - Applying and evaluating a new approach for risk assessment suggested by the Swedish Agency for Water and Marine Management
Examensarbete för masterexamen
Infrastructure and environmental engineering (MPIEE), MSc
The aim of this master thesis is to evaluate the applicability of a new approach of risk assessment for water protection areas in Sweden. This was achieved by applying the risk assessment approach on four water sources that previously were assessed based on a common approach of risk assessment. The results from both risk assessments were compared and analysed in terms of risk sources characterisation, estimation of risk levels and presentation of the result. It was found that the new approach in general adds significant value to the risk assessment. Mainly, by describing the physiological properties of the contaminants, consequences of contamination, and the waterworks ability to treat the contaminants. Furthermore, by including a pathway description of risk sources, the risk level could be efficiently described and motivated, which in turn makes it easier to motivate and describe restrictions in water protection areas. It was also found that the new approach is applicable on groundwater and surface water sources in both urban and rural areas. The factors that influenced the performance of the new approach the most were primarily the number of risk sources and the level of detail of the risk assessment. When the water source is particularly large, the common approach was considered more easily applicable to assess the risks. To further improve the new approach, it is recommended to provide information about common drinking water contaminants, such as their physiological properties, health affects on humans, treatment processes in waterworks and related risk sources. It is also recommended to include guidance of how the contaminants efficiently can be grouped. Regarding future studies on the new approach, it is recommended to investigate how to incorporate and assess the risk related to future threats, water shortage and unplanned pathways.
Risk Assessment , Water Protection Area , Source Water Protection