World Water Day 2017 author series: Guenter Langergraber

Name and title(s): Dr Guenter Langergraber. Areas of expertise: Resources-oriented sanitation; treatment wetlands; modelling. Guenter Langergraber is Editor of the journal of Water Science and Technology and co-author of the book Guidelines for Using Activated Sludge Models. Questions This year, the UN’s World Water Day is dedicated to topics in wastewater. What do you think/hope this will achieve? Wastewater treatment and sanitation will be put in focus to the public and for politicians which is important to increase awareness. Why is the topic of wastewater important? A sanitation system only provides the expected benefits to health and environment if all parts of the sanitation service chain are working well. Wastewater treatment is an essential part of the chain also in relation to the UN Sustainable Development Goal (SDG) number 6 that request that wastewater needs also be treated. However, the world's focus must shift towards those areas that are not connected to sanitary sewers up to now. Non-sewered sanitation solutions and faecal sludge management will have to be prioritized to achieve the overall SDG 6 targets. What do you think is the most significant change or development in wastewater research/treatment in recent years? As mentioned above, faecal sludge management has to become highest priority to achieve SDG 6 on global scale. Water-borne sanitation solutions are not applicable in a very large number of locations due to lack of water and/or too high costs for implementing sewer systems. How might you suggest people get involved and/or learn more about the significance of wastewater?