After drinking water in the future might mean a visit to the bank - more particularly the river bank. Scientists at Johns Hopkins University are testing a theory that it might be better to take water from wells drilled adjacent to rivers than directly from the river itself. The idea is called river-bank filtration. The theory holds that allowing the river water to pass through a hundred feet or more of earth might strip away some unwanted pollutants including viruses, protozoa and bacteria. The work is important because antibiotic resistant microbes and some cancer-causing chemicals could occasionally pass through traditional water treatment according to lead researcher Dr Edward J Bouwer. "Some bacteria are becoming more resistant to disinfection. We are also worried about the by-products created during disinfection. Some of them may be carcinogenic," he said.