In the framework of the Diderot Mathematical Forum (DMF) of the European Mathematical Society (EMS), December 19-20, 1997, a Videoconference was held linking three teams of specialists in Amsterdam, Madrid and Venice respectively. The general subject of this videoconference, the second one of the DMF series, was Mathematics and Environment and more specifically, Problems related to Water. This volume contains the texts of the Madrid site contributions with important, new and unpublished, examples on the modeling, mathematical and numerical analysis and treatment of the associated control problems of relevant questions arising in Oceanography and Environment.