Focal depths of earthquakes help reveal the seismogenic structure and crustal rheology, as well as the rupture nucleation process and coseismic rupture propagation process. In regions with dense seismic network, focal depth can be usually estimated precisely with travel time of Pg and Sg, which is challenging in the sparse network. In this article, we model the recently proposed local depth phase sPL to determine the focal depths of the aftershock sequence of the 2011 Virginia earthquake. The depth solutions of 10 M 2.5+ events are consistent with results determined with dense temporary stations, with a maximum difference less than 1 km and average deviation less than 0.5 km. This study indicates that reliable focal depth can be obtained via modeling sPL with waveform records from one or a few seismic stations, implying the applicability in sparse network.