One of the main concerns in slurry transport is the pipeline plugging. Plugging will not only cause engineering safety problems, but also cause economic losses. As a result, determination of critical velocity under certain working conditions is an important method to prevent blockage. Therefore, researching the critical velocity has great value on improving the efficiency of pipeline transport and optimizing the construction process. Currently, there are many definitions and formulas on the critical velocity, mostly empirical formulas, and it cannot be used in the dredging projects accurately. In order to obtain the role and value of these critical velocity models, this paper uses seven critical velocity models under the engineering condition of “Daxiaodeng fill and reclamation project” in Xiamen, China. In this paper, the calculated critical velocity is compared with the measured velocity. It is concluded that under the soil and working conditions in Xiamen, when the concentration is within 30%, the Durand model and IHC-MTI model are recommended to calculate the critical velocity. When the concentration is above 30%, the Durand model, IHC-MTI model and Wasp model are recommended to calculate the critical velocity.