[en] The combined experimental and theoretical works of the study of the absolute single and double electron loss (stripping) and single and double electron capture cross sections for 0.2-1.2 MeV O⁺ projectiles colliding with water molecule are presented. In order to mimic the experimental observation we performed three, four and five-body classical trajectory Monte Carlo calculations. In our model the O⁺ projectile is either one, (two or three) particle(s) depending on the model used (3, 4 or 5 body model, respectively) and the water target is taken into account as two virtual particles. We found that the calculated cross sections are in agreement with the present experimental data. Moreover, the similarity of the present data with an isoelectronic system, the methane molecule allows us to draw a common curve through both data sets. (authors)