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WATER SAFETY PLANS (WSP) AND EXPERIENCESWITH SMALL-SCALE WATER SUPPLY SYSTEMSMargriet SamwelWomen in Europe for a Common Future – WECF, The NetherlandsEmail: margriet.samwel@wecf.eu, Website: www.wecf.euIntroductionThe Stockholm Framework (2001) provides aharmonized approach for the development of health-basedguidelines and standards in terms of water and sanitationrelated hazards. Coinciding with the development of thisframework was the realization that drinking water safetycould no longer be guaranteed solely through monitoringat the so-called ‘end of pipe’ and the increased need toaugment traditional sources of water supply (potable andnon-potable) with re-used water. Both of these factorsrequired a more preventative risk-based approach tomanaging water for the protection of public health.Hence the World Health Organisation (WHO) initiatedthe Water Safety Plans (WSP), which is to be consideredas a part of the WHO or other guidelines or directives ondrinking water quality. The WSP asks for an identificationof risks, which could affect water safety and human healthin every stage of the water supply.What is a Water Safety Plan?A Water Safety Plan (WSP) is a most effective way ofensuring that a water supply is safe for human consumptionand that it meets the health based standards and otherregulatory requirements. It is based on a comprehensiverisk assessment and risk management approach to allthe steps in a water supply chain from the catchment tothe consumer.The primary objectives of a water safety plan inprotecting human health and ensuring good water supplypractice are the minimisation of contamination of waterresources, the reduction or removal of contaminationthrough appropriate treatment processes and theprevention of contamination in the distribution networkand the domestic distribution system. These objectivesare applicable to all water supply chains, irrespective oftheir size or complexity.The WSP focuses on the safety of all the differentaspects of a water supply, which can vary from a large-scale supply providing water to several million consumersto a small-scale system, e.g. a bucket-well. The WSP isa concept to develop a process-orientated observation ofthe water supply and its goal is to identify and eliminate allthe possible risks in the entire water supply system: fromthe potential risks of water pollution in the catchment areaall the way along the line to the consumers.The approach of a WSP can be adopted to all waterand sanitation systems, such as surface water, rainwaterharvestingor sanitation facilities.The base of every Safety Plan is the understandingof the system and collection of all relevant informationabout the nature and properties of the water or sanitationsystem and the activities taken place in the target area 1 .Catchment• geology, hydrology, meteorology and weatherpatterns• nature of the land and it use, in particular degreeof urbanisation, industrial activities, animal rearing andarable farming, degree of natural land and its wildlife,quarrying and mining (that is uses and activities that couldgive rise to contamination of raw water sources)• competing water uses such as irrigation and rivercompensation flows• planned future activities• any existing catchment control and protectionzonesSurface water• type of water such as river (direct abstraction), river(abstraction in storage reservoir), impounding reservoir,lakeSource: DWI – A brief guide to drinking water safety plansOctober 2005Fig. 1. The components of a Water Safety Plan (WHO)— 195 —