How to manage risks in entire water supply chain: Manual by WHO, IWA has tips for suppliers
Drinking water contamination is a global environmental problem that harms people as well as aquatic creatures and plants. Access to clean and safe drinking water is, thus, a major problem for everyone.
Safe drinking water management must consider the quality, acceptability and quantity of drinking water to protect the public health. Unorganised systems prevent billions of people from having access to clean and safe drinking water.
In order to meet the need for a safe drinking water supply, innovative and complex wastewater treatment methods are needed. These methods include primary, secondary and, in certain cases, tertiary wastewater treatment.
Recently, the International Water Association (IWA) and the World Health Organization (WHO) have produced the second version of the Water Safety Plan Manual, which provides practical assistance for developing and implementing water safety plans in compliance with the WHO drinking water quality recommendations.
It supports the management of drinking water supplies through water safety planning, which employs a thorough risk assessment and risk management strategy to ensure the security of a drinking water supply.
The manual has been updated for the second edition to address new water sector issues such as climate change, equity and resilience. The target audiences in this guidebook are water suppliers, organisations like non-profit governmental or international organisations, academic or research institutions and water sector professionals, who support water safety programmes or agencies responsible for public health, regulations and surveillance.
The manual offers a variety of case studies from low- to high-income nations, showing solutions to real-world problems to aid readers in applying the advice in various circumstances.
As drinking water is the ultimate product of the production chain, it is regulated to guarantee that it is secure and of sufficient quality. Monitoring the final product has been the usual procedure to determine whether it is of adequate quality.
Risks, however, may not be discovered at all or may not be discovered until it is too late. Water safety planning is a proactive risk assessment and management technique to assure the safety of drinking water from the source to consumers.
The most dependable method of managing drinking water supplies to preserve public health is universally acknowledged as the systematic water safety planning process. Water safety planning manages risk throughout the entire water supply chain, which is processed through various stages like:
- Sources (catchment or raw water storage)
- Treatment (or disinfection)
- Distribution and storage (free chlorine residual maintenance and closed system)
- Users (safe storage, treatment, and handling)
Disinfection is the most crucial and essential process in wastewater treatment for public water supply. The chlorination process is the cheapest, most realistic and most successful approach for attaining the best results.
Thus, reclaimed water is highly required for environmental sustainability and to meet United Nations-mandated sustainable development goals. In addition, economic studies — cost-benefit analysis for treatment — need to be further investigated to determine economically feasible technologies.
Planning for water safety has been used in every part of the world, with various types of water supplies and in a wide range of socioeconomic sectors. These have seen decreased cases of various waterborne diseases, mainly diarrhoea, better microbiological testing and quality control in reclaimed or treated water, increased consumer confidence and better approach in water stakeholders and consumer communities, reduced operational costs and usage of chemicals in the treatment process and, most importantly, reduced toxic disinfection by-products formation.
This manual has also provided several case studies for each problem and global studies on safe and clean drinking water supply, which should be considered as best opted examples and could help in implementing regulations and legislations.
Proactive management is implementing plans for both anticipated and unanticipated future occurrences, such as climate variability, climate change, natural catastrophes, war, epidemics and pandemics.
Effective water safety planning must take into account the water supply sensitivity to present and future consequences from climate variability and climate change. To prove safety, it is not enough to show that the water supply is safe under normal circumstances; the controls must also work well in emergency situations based on past exceptional events or likely future scenarios.
Control mechanisms, thus, are essential for managing safe drinking water and must always be effective to reduce risks, along with emergency response plans for effective management and uniformity in performance.
Control measure in monitoring gives operators a quick feedback on how well they are working and alert them when a control measure is not operating within expectations. Water suppliers may already monitor control measures as part of their operational activities.
Views expressed are the authors’ own and don’t necessarily reflect those of Down To Earth.