The Urban-Rural Nexus and its role for solving the global water quality challenge Prof. Dr. Dietrich Borchardt (UFZ and TU Dresden)

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1 Urban-Rural Nexus and its role for solving the global water quality challenge Prof. Dr. Dietrich Borchardt (UFZ and TU Dresden)

2 Two forces in a cutting-edge cluster

3 Focus and activities of CAWR

4 Capacities of CAWR

5 Governance International Alliance Saxony (IWAS) and the approach of the CAWR of surface water, matter and solute fluxes Latin America Brazil urban water resources management with increasing growth Scenarios and systems analysis Eastern Europe Ukraine Middle East Oman/Saudi-Arabia Groundwater recharge, safe yield & agriculture/ irrigation Development of technology and implementation Central Asia Mongolia balance and land use in climatesensitive regions South-East Asia Vietnam Waste water and sludge utilization for groundwater recharge & agriculture Capacity Development

6 Pre-study for a Ilona Bärlund, Martina Flörke, Jeanette Völker, Andrew Kaus, Marcus Malsy, Klara Reder, Olaf Büttner, Christiane Katterfeld, Désirée Dietrich, Alejandra Matovelle, Joseph Alcamo, Dietrich Borchardt

7 quality challenge Wastewater production at least doubling by 2050 Sewerage connections increasing But not wastewater treatment More untreated wastewater to rivers and lakes Health: Health risk of contaminated rivers & lakes contact with surface waters washing, cleaning, drinking Food Security: 95% inland fishery production from developing world 200 million Africans consume fish regularly

8 About the assessment Two-stage assessment Model and data driven analysis in parallel Global coverage, with focus on developing countries Freshwater, inland waters (running waters and lakes) Identify current hotspots of deteriorating water quality (focus on BOD, FC, TDS, totn/totp) types, intensity and sources of water pollution of potential impacts relating to human health and food security (freshwater fishery) Identify main water quality data and information gaps

9 Generic concept generic concept behind the assessment: PE BOD WQ for fish; Fish catch and consumption D Drivers P Pressures S State I Impacts R Response Populat. growth Waste water load Conc. BOD, NH4 +, Food security SDGs eg. connec. x% of pop. to sanit. + - Efficiency of WWTPs

10 Data driven analysis example oxygen Status Trend

11 Model driven analysis example fecal coliforms Description :- Estimated in-stream concentrations of faecal coliform bacteria (FC) for Latin America, Africa and Asia for February Bar charts show minimum and maximum monthly estimates of river stretches in the severe pollution class per continent in the 36-month period from

12 quality and food security: intake from inland fishery Description :- Estimation of the level of consumption of inland fisheries per person per country. Method :- Reported inland fisheries catch (t) divided by the official national population. Categorisation :- Higher risk: 1,86 kg/capita/2010 and Lower risk: < 1,86 kg/capita/2010 (75 th percentile of countries reporting inland fisheries yields)

13 quality and food security: trend in inland fishery Description :- Determine increasing or decreasing trends of inland fisheries catches per country over recent decades. Methods :- average catch for and was calculated and then the percentage difference between both periods was determined as either a positive or negative trend. Categorisation :- Lower risk: positive / increasing trend (> 0 %) or Higher risk: negative / decreasing trend (< 0%)

14 quality and food security: BOD hot spots Description :- Percentage of river stretches in each country with increasing trend of BOD of particular concern meaning that in these stretches the pollution level increased into the severe pollution category in , or that they were already in the severe pollution category in and further increased in concentration by

15 Main messages of the WWQA Phase 1 pollution has worsened since the 1990s in almost all rivers in Latin America, Africa and Asia. Severe pathogen pollution already affects around onethird of all river stretches in Latin America, Africa and Asia. number of people at risk to health by coming into contact with polluted surface waters may range into the tens of millions on these continents. Severe organic pollution already affects around oneseventh of all river stretches in Latin America, Africa and Asia and is of concern to the state of the freshwater fishery and therefore to food security and livelihoods.

16 Main messages of the WWQA Phase 1 immediate cause of increasing water pollution is the growth in wastewater loadings to rivers and lakes. Ultimate causes are population growth, increased economic activity, intensification and expansion of agriculture, and increased sewerage with no or low level of treatment. Although water pollution is serious and getting worse in Latin America, Africa, and Asia, the majority of rivers on these three continents are still in good condition.

17 Main messages of the WWQA Phase 1 A wide range of technical options are available to developing countries for water pollution control and for short-cutting the negative trends. se include: Pollution prevention and source control Wastewater treatment Safe reuse Protecting and restoring aquatic ecosystems quality issues are closely linked with society s priorities such as health, food security and water security. It is important, therefore, that a nexus approach is taken for solving the global water quality challenge.