Monday 19 September 2011 the HRWM conference kicked off by an energetic Maori welcome. Apart from the tribal welcome, Maori representatives also gave their view of water, and how it is embedded in their own identity. They stressed the need for emotional en spiritual healthy water. The first technical sessions on microbial water risks during emergencies and under climate change stress were led by dr. Gertjan Medema. First hand experiences from the earthquake in Christchurch and the cholera epidemic were shared. How do you handle a 1 m thick layer of sewage contaminated sludge spread out over a city where all drainage has been blocked? How can you treat hospital wastewater during a cholera epidemic in an emergency situation to prevent spreading of the disease?

 

Several speakers highlighted that on the long term climate change can increase microbial risks. Paul Hunter showed how more heavy rainfall events can lead to outbreaks especially at small supplies. Jack Schijven quantified the combined effects of changing precipitation patterns and increase of temperature on the fate and transport of pathogens in river water. The effect on persistent organisms like norovirus or Cryptosporidium differs from that on vulnerable organisms like Campylobacter. The afternoon session on catchment protection generally highlighted the shortcomings of indicator organism monitoring and presented several alternatives to characterize risks in the catchment. Bacteriodes typing is increasingly used to differentiate between human and animal contamination in the catchment but the search for the ideal indicator parameter continues.

 

Patrick Smeets, PhD
Scientific researcher