In this paper we analyze the use of time splitting techniques for solving
shallow water equation. We discuss some properties that these schemes should
satisfy so that interactions between the source term and the shock waves are
controlled. This paper shows that these schemes must be well balanced in the
meaning expressed by Greenberg and Leroux [5]. More specifically, we analyze in
what cases it is enough to verify an Approximate C-property and in which cases
it is required to verify an Exact C-property (see [1], [2]). We also include
some numerical tests in order to justify our reasoning