We consider the problem of routing uniform communication instances in switched optical tori that use the wavelength division multplexing (or WDM) approach. A communication instance is called uniform if it consists exactly of all pairs of nodes in the graph whose distance is equal to one from a specified set S = d 1; d2;...; d k. We give bounds on the optimal load induced on an edge for any uniform instance in a torus Tnxn. When k = 1, we prove necessary and sufficient conditions on the value in S relative to n for the wavelength index to be equal to the load. When k≥ 2, we show that for any set S, there exists an n0, such that for all n > n0, there is an optimal wavelength assignment for the communication instance specified by S on the torus Tnxn. We also show an approximation for the wavelength index for any S and n. Finally, we give some results for rectangular tori.