In this paper a new approach to generate strategies for hydro reservoir scheduling is presented. The idea is that the marginal value of water in one reservoir can be calculated by dynamic programming under some simple assumptions on the content in other reservoirs. A benefit of this approach is that one avoids the 'curse of dimensionality' by having to calculate water values for all combinations of reservoir content in the different reservoirs. Water values for all reservoirs can be found simultaneously for each reservoir content level. The method is compared to state-of-the art methods in hydropower scheduling and promising results are observed. © 2013 IEEE.