This repository provides the source code based on MARS3D model code (Lazure and Dumas, 2008), with modifications for the LANS-alpha implementation (Hecht et al, 2008). Model outputs of an application on the Alderney Race are also provided. Simulations with and without LANS-alpha have been performed for two days (29-30 September 2017), with model configurations at two different horizontal resolutions (120 and 30 meters). Two cases have been considered for the vertical mixing parametrization, with the use of the k-epsilon turbulent closure and a constant vertical viscosity of 0.2 m2.s-1 .