We investigate the impact of a light sterile neutrino 1eV on the prospective data expected from currently running long-baseline experiment NOvA and future experiment DUNE. If an eV scale sterile neutrino exists, and has non-zero mixing with the other neutrinos then nature of the predictions for the mass hierarchy (MH), CP-violation and octant by these two experiments will be modified. Parameter degeneracy resolution is a key part of neutrino oscillation physics as there are a multitude of degeneracies that make distinguishing certain results difficult. It has been shown that in the three neutrino case, for certain favoured combinations of the CP phase and the mass ordering, NOvA can resolve the MH and octant degeneracies. On the other hand, DUNE should have no problem with these degeneracies once is is complete and running. It is interesting then, in light of recent data showing favourable true values, to analyse the effect of adding a light sterile neutrino and to see whether sensitivity to any of these degeneracies is lost. We use revised best fits and study the sensitivity of these two experiments to degeneracies in the presence of new active-sterile mixing angles and Dirac CP-violating phases.

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