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Source water protection (SWP) is the most important step in the implementation of a multi-barrier approach that ensures cost-effective delivery of safe drinking water. However, implementing SWP strategies can be a challenging task owing to technical and administrative issues. Decision support tools for effective implementation of SWP strategies can be very helpful that may lead to saving time and resources. This paper critically reviews different SWP strategies available for surface waters and also discusses various formulations for water quality assessment at the source. Source water quality regulations in Canada and other jurisdictions around the world are also discussed. Stormwater management ponds, vegetated filter strips, pollution control by effective agricultural practice (e.g., cover crop and crop rotation) and fencing are found to be frequently mentioned in those regulations. These strategies are discussed in details in terms of their key features to achieve the highest possible removal efficiencies for selected water quality parameters. Finally, a conceptual model is proposed to evaluate water quality changes at the source based on selected source water protection strategies. The model uses SWP strategies as a means to reduce possible pollutants in the source water. It also utilizes simple mass balance equations (dilution) to estimate the concentrations in the receiving water bodies and does not consider physicochemical and other reactions. A surrogate measure, water quality index (WQI), based on selected water quality parameters, is used for the assessment of source water quality. Key words: source water protection strategy, water quality index, low-impact development (LID), best management practices (BMP), stormwater management, conceptual model, fuzzy-based methods. La protection des sources d'eau (<< SWP >>) constitue l'etape la plus importante dans la mise en oeuvre d'une approche a barrieres multiples pour assurer la livraison d'eau potable fiable a un cout efficace. Cependant, la mise en place de strategies de protection des sources d'eau peut constituer un defi impliquant des enjeux techniques et administratifs. Des outils d'aide a la decision pour la mise en place efficace de strategies de protection des SWP peuvent s'averer fort utiles pour sauver du temps et des ressources. Les auteurs revoient, de facon critique, differentes strategies de protection des sources d'eau SWP disponibles pour les eaux de surface et discutent diverses formulations pour revaluation de la qualite de l'eau a la source. Les reglementations sur la qualite; des sources d'eau au Canada et dans d'autres juridictions a travers le monde sont aussi analysees. Les bassins pour la gestion des eaux des tempestes, les bandes filtrantes vegetales, le controle de la pollution par des pratiques agricoles efficaces (e.g., culture de couverture et rotation de cultures) et l'utilisation de cloture constituent des strategies frequemment citees dans ces reglementations. Ces strategies sont discutees en detail en ce qui concerne leurs caracteristiques fondamentales pour aboutir aux niveaux d'efficacite les plus eleves possibles relatifs a l'elimination des paramtetres de qualite d'eau (<< polluants >>) selectionnes. Enfin, les auteurs proposent un modele conceptuel pour evaluer les changements de la qualite de l'eau a la source, base sur les strategies de protection des sources d'eau selectionnees. Le modele utilise les strategies de protection des SWP comme un moyen pour reduire les charges possibles de polluants vers la source d'eau. Il utilise aussi des equations simples de bilan de masse (<< dilution >>) pour estimer les concentrations de polluants au niveau des plans d'eau recepteurs; il ne considere pas les reactions physico-chimiques ou autres. Une mesure de substitution, un indice de qualite d'eau (<< WQI >>), base sur les paramtetres de qualite; d'eau choisis, est utiliseee pour revaluation de la qualite des sources d'eau. Mots-cles: strategie de protection des sources d'eau, index de qualite; de l'eau, developpement a faible impact (LID), meilleures pratiques gestion (BMPs), amenagement de l'eau des tempetes, modele conceptuel, methodes basees sur la logique floue. [Traduit par la Redaction], 1. Introduction The goal of source water protection (SWP) strategies is to save the source water from a potential pollution source. Though source water refers to both ground and surface [...]

For the last few decades, concerns have repeatedly been raised about deteriorating water mains in Canada. Small to medium sized water utilities are generally impacted more due to lack of technical and financial resources. This paper presents a user-friendly life cycle cost (LCC) analysis-based decision support tool to help these utility managers to prioritize water mains rehabilitation or replacement (R/R) strategies. The deterioration curves for water mains of different materials and sizes have been developed based on their likelihood of failure. The proposed model is implemented for the water supply network of City of Kelowna (Canada). It compares the costs of various R/R scenarios for each pipe over its life cycle and suggests the most cost-effective decision to the managers to efficiently allocate their limited resources. [ABSTRACT FROM AUTHOR]

All over the world water mains are under increasing threat due to aging, aggressive environmental factors, operational factors and inadequate maintenance. Extensive maintenance, repair and rehabilitation practices, or replacement of water mains are required to ensure an acceptable performance of water supply systems. Investment deficit for water system maintenance and rehabilitation has been estimated in billions. Small to medium sized water utilities are generally impacted more because of limited financial resources and lack of technical expertise. However, water mains integrity is of primary interest due to potential adverse consequences related to public health, safety, and heavy financial liabilities in case of a failure. This paper presents a user-friendly decision support tool to help managers of these water utilities to prioritize maintenance, repair, and replacement (M/R/R) strategies for water mains. This paper proposes a risk index approach which aggregates the water mains vulnerability and associated failure consequences. The developed tool can help decision-makers to rank the water mains and help to prioritize M/R/R strategies. The results have been integrated with a geographic information system that will allow a decision-maker to visualize the vulnerable zones within the network. The City of Kelowna water network is used to demonstrate the proposed approach. [ABSTRACT FROM AUTHOR]