Jun 7, 2011 in Blog Articles

It would seem that the outbreak of E coli and subsequent HUS deaths is going to be traced to contaminated irrigation water. That is, contamination caused by farmyard manure or slurry produced on farms or else it is from inadequately treated wastewater from municipal treatment plants. And this outbreak is happening in Germany, not in Africa.But treated wastewater can be safe. Take a country like Jordan which has been categorised as the 4th water-poorist nation on earth. And yet almost 50 percent of the Jordan Valley (the nation’s food basket) is irrigated with treated wastewater from Khirbet Al Samra Wastewater Treatment Plant. A total of 100 million cubic meters of wastewater is treated annually. One advantage of treated wastewater reuse is saving the cost of synthetic fertilsers because treated wastewater is rich in plant nutrients.Is the Jordanian treated wastewater really safe for the irrigation of vegetables? Yes, according to Professor Duncan Marra of the civil engineering department at the University of Leeds, “I have seen good farming practices…Jordan applies the safest treated wastewater schemes that I have probably ever seen in the world.”How is this accomplished when there are known risks associated with treated wastwater particulary from microbiological pathogens? Well, tests have shown that 99.3 percent of ten types of vegetables irrigated with treated wastewater are free from pathogens…these tests were carried out on several types of crops which are eaten raw such as tomato, lettuce, cucumber, bell pepper, mint and parsley.  You would not expect to find an E coli outbreak in a first world country like Germany but it just goes to show that that wherever treated wastewater, farmyard manure or slurry is used for irrigation or as fertilser, there will be inherent risks.