if you replace the idea of the water getting infected, with the idea of meat then it becomes i bit more realistic. As England has had to deal with similar cases in the past, such as;

In February 2001, the USGAO reported that the FDA, which is responsible for regulating feed, had not adequately policed the various bans. Compliance with the regulations was shown to be extremely poor before the discovery of the Washington cow, but industry representatives report that compliance is now 100%. Even so, critics call the partial prohibitions insufficient. Indeed, US meat producer Creekstone Farms alleges that the USDA is preventing BSE testing from being conducted.