Surface velocity of the molten steel is critical to final product quality during the continuous casting of steel. Plant experiments using two different new sensors, Sub-meniscus Velocity Control (SVC) devices and nail dipping, are performed to evaluate their performance, and to quantify liquid steel velocities at locations 50 mm apart on the surface of ArcelorMittal Dofasco's No. 1 continuous caster under different casting conditions, including different throughputs and mold widths. Correlation between the height difference of the solidified lump on the nail and surface velocity is confirmed and extended. Reasonable agreement between the two sensing methods of surface velocity is obtained, both in trends and magnitudes for both time-averaged velocity and transient flows. The effects of casting speed, mold width, and gas volume fraction on meniscus velocity are also discussed.