Work package 2
Climate change impacts on water quality (lead: FMR and FRCH)
In WP 2 the impacts of climate change on water quality are assessed under consideration of socio-economic changes. Beside physio-chemical water quality parameters we will lay a special focus on microorganisms which may cause diseases in humans including. E. coli as an indicator of faecal contamination and specific pathogens like Vibrio cholerae. Activities in this WP are:
Activity 2.1: Establish a data base on historical data on water quality, supplemented with new water analysis: Historical data on water quality e.g. from Tambe et al (2008) and Bahador et al. (2004 and 2005) will be collected and linked to climate and hydrological data. Additional water sampling under varying weather conditions will be performed (see activity 2.2.). Afterwards the data will be analyzed for correlations between climate and hydrological parameters and water quality.
Activity 2.2: Water sampling and analysis: To find out how weather conditions influence water quality we will analyse water samples over nearly the whole project period. The first year we will screen several drinking water sources in our case study areas as e.g. water reservoirs, rivers, bore holes, standposts and household supplies, to indentify “hot spots” with poor water quality. The sampling stations will be located in flood and drought prone areas (input from activity 1.1 and based on experience from former studies). The sampling campaigns will be accomplished under different weather conditions as e.g. beginning, middle and end of dry season and monsoon season, and in certain time intervals after rainfall events. The samples will be analysed for faecal indicator bacteria (e.g. E. coli, coliforms and enterococci) and standard physio-chemical parameters (conductivity, turbidity, nutrients, etc.).
In year 2 and 3 sampling will be limited to identified hot-spots and triggering weather events, but the samples will undergo a more extensive analytical programme, including total coliforms, enterococci (and Clostridium perfringens) as indicators for faecal contamination. A few specific pathogenic bacteria (like V. cholerae, Salmonella spp., or Campyobacter spp), parasitic protozoa (Cryptosporidium and Giardia) or viruses (like rotavirus, hepatitis or others) may be included depending on the results from the literature study about emerging pathogens (activity 2.3). Additionally also emerging substances like pesticide residuals or heavy metals will be analysed if relevant for the choosen hotspots.
Activity 2.3: Literature review on emerging substances and microorganisms affecting water quality: To define future “threats” to water quality a literature study on emerging substances and organisms under changing climate and socio-geographic conditions (input from activity 3.1) will be perfomed.
Activity 2.4: Develop scenarios for “future normal” and “future extreme” conditions for water quality and suggest water improvement options: Considering the results of activity 2.1 to 2.3, future water availability and climate conditions (WP 1) and socio-geographic trends (activity 3.1), different scenarios, which reflect future conditions of water quantity and quality will be developed. The scenarios will be develop offsetting factors which affect the magnitude of pollution as e.g. population growth, intensified agricultural development against factors affecting the dilution as e.g. water flow, retention. Based on these scenarios we will suggest water improvement options including optimised drinking water treatment at plant level (cooperation with activity 3.4).