Sanitation safety planning as a tool for achieving safely managed sanitation systems and safe use of wastewater.

Increasing water stress and growing urbanization force a greater number of people to use wastewater as an alternative water supply, especially for irrigation. Although wastewater irrigation in agriculture has a long history and substantial benefits, without adequate treatment and protective measures on farms and in markets, use of wastewater poses risks to human health and the environment. Against this background, the World Health Organization (WHO) published Guidelines for the safe use of wastewater, excreta and greywater in agriculture and aquaculture, in 2006. The Sanitation safety planning: manual for safe use and disposal of wastewater, greywater and excreta - a step-by-step risk-based management tool for sanitation systems - was published by WHO in 2016 to put these guidelines into practice. Sanitation safety planning (SSP) can be applied to all sanitation systems, to ensure the systems are managed to meet health objectives. This paper summarizes the pilot-testing of the SSP manual in India, Peru, Portugal, Philippines, Uganda and Viet Nam. Also reviewed are some of the key components of the manual and training, and an overview of SSP training and dissemination efforts and opportunities for implementation in the WHO South-East Asia Region. Lessons learnt during the piloting phase show how reducing health risks can be surprisingly easy, even in a low-income setting, especially when combining many smaller measures. The SSP approach can make an important contribution towards Sustainable Development Goal target 6.3, by reducing pollution, eliminating dumping and minimizing the release of hazardous chemicals and materials, thereby halving the proportion of untreated wastewater and substantially increasing recycling and safe reuse globally.

The influence of untreated wastewater to aquatic communities in the Balatuin River, The Philippines.

A risk assessment of chemical constituents in rivers that receive untreated wastewater should take into account the adverse effects of increased biological oxygen demand (BOD), ammonia and reduced dissolved oxygen (DO). This concept was tested via a field study in the Balatuin River, The Philippines, where the influence of physical and chemical factors, including the consumer product chemical linear alkylbenezene sulfonate (LAS), to aquatic communities (algae, invertebrates, fish) was determined. Periphytic algae were found to be insensitive to high BOD (>10 mg/l) and ammonia (>0.01 mg unionized NH(3)/l), concentrations from organically enriched untreated wastewater discharges. However, taxa richness and abundance of macroinvertebrates were influenced greatly by the discharges. Where BOD and ammonia concentrations were elevated, the dominant taxa were oligochaete worms and chironominds. Fish and crustaceans (freshwater crabs and prawns) were found only in sites with the least BOD concentrations (furthest upstream and downstream). The maximum concentration of LAS (0.122 mg/l) was less than that expected to affect 5% of taxa (0.245 mg/l), whereas exceedences of DO and ammonia criteria were observed in several sites. The lack of recovery observed was attributed to influences of low DO, high ammonia and poor colonization from upstream and downstream reaches due to organically-enriched discharges