Cross Flow Turbine Generator Unlike most water turbines which have axial or radial flows, in a cross-flow turbine, water passes through the turbine transversely or across the turbine blades. As with a water wheel, the water is admitted at the turbine’s edge. After passing the runner, it leaves on the opposite side. Going through the runner twice provides additional efficiency. When the water leaves the runner, it also helps clean the runner of small debris and pollution. The cross-flow turbine is a low-speed machine that is well suited for locations with low head.