If you watch the platform near the wheel, you'll see that the water is actually going down since forward it the platform is in a lower level. I'm not an expert

If you watch the platform near the wheel, you'll see that the water is actually going down since forward it the platform is in a lower level. I'm not an expert but, I haven't ever seen a pump making water flow that way, so maybe the water is always going down and the illusion is made by the camera position over a near flat object. Maybe you could tell the track position by watching how the water flows through corners... a pretty weird way if you watch closer...