Water was exposed for different times to weak static magnetic field (MF) generated from a stack of magnets (B = 15 mT) or from a single permanent magnet (B = 0.27 T) at flow conditions. The water conductivity and the amount of evaporated water were measured as a function of time following the application of MF. It was found that the MF decreases the water conductivity, which is inversely proportional to the flow rate, and increases the amount of evaporated water, even after the water's distillation. The effects are due to the hydrogen bond network strengthening and the perturbation of gas/liquid interface from the air nanobubbles in the water. (C) 2010 Elsevier BM. All rights reserved.