Quantifying the Impact of Flooding on Waterborne Pathogens at river Kabul basin areas, Pakistan

Diarrhoea is the 3rd leading cause of death in developing countries. Diarrhoea outbreaks are related to periods of heavy rainfall and runoff. It has been found that heavy rainfall increases diarrhea outbreaks due to contamination of the water distribution systems. The risk of diarrhoea is related to the concentration of waterborne pathogens in the surface water. An increase in polluted surface water may therefore increase the risk of diarrhoea in the area.

The main sources of faecal pollution in surface water are sewage and animal manure. In developing countries, such as Pakistan, the sanitation and treatment of sewage are insufficient. Sewage and animal manure may enter the surface water directly.  In my study I will look at the concentration of E. coli (a faecal indicator that is measured widely) in the surface water. This concentration could increase due to an increased flooding risk in the area. The main reasons for an increase are that the flood water flushes more sewage and manure into the surface water. At the same time, however, increased flooding could also dilute the pollution. An increased temperature may increase the growth of E. coli in the surface water. The microbiological water quality is further aggravated due to the lack of proper management at times of flood.

Observations in Kabul river and its tributaries have shown faecal indicators present in the water. Elevated concentrations of faecal indicators have been observed after the flooding events of 2010. In the face of climate change, flooding events are expected to occur more often in the future. In flooded towns, such as Nowshera, people are exposed to water polluted with faecal contamination and possibly also waterborne pathogens that pose a health risk. Expectations are that the health risk increases due to climate change. Although it is essential to get a better understanding of the situation for the population, quantitatively, it is unclear how the microbial water quality is actually influenced by climate change. That is the objective of my study.

Project results

The project is highly important for evaluating the options for ground and surface water quality management. It will supplement the past research on impact of climate change on the water cycle, and integrate it with current water quality aspects. The study will add to and generate new information and knowledge on climate research.


This study aims to quantify the concentration of waterborne pathogens (Coliform, E. Coli) in river Kabul basin areas in Pakistan before, during and after flood periods now and in the future.


  • Measurement of E. coli concentrations at several locations in and around river Kabul before, during and after flooding.
  • Using the SWAT model to estimate the concentration of E. coli in Kabul river. The model will be validated with the observed concentrations.
  • Developing flooding scenarios for river Kabul based on IPCC AR5 scenarios.
  • Scenario analysis of changes in E. coli concentrations in Kabul river with a changing climate, using the SWAT model and developed flooding scenarios.

Expected results

  • Observed concentration of E. coli in river Kabul.
  • A model (based on SWAT model) that estimates the concentration of waterborne pathogens in river Kabul basin area (Nowshera, Charsadda, Warsak and Peshawar).
  • New scenarios for flooding.
  • Assessment of the consequences of flooding on E. coli concentrations in river Kabul.