The location of vacuum sources with negative pressures was considered in analysis of the effects of dredger fill foundation reinforcement under vacuum preloading. Model tests were performed to simulate dredger fill foundation reinforcement using the vacuum preloading method, with vacuum sources located at the top and bottom. Over the course of foundation consolidation, the amounts of water drainage and settlement for different soil layers and the vacuum degree at different depths were monitored, and the transmission efficiency of the vacuum degree and consolidation settlement properties for soil layers with vacuum sources located at different depths were studied. Results show that the vacuum preloading method, with vacuum sources located at the bottom of the dredger fill foundation, can enhance the transmission efficiency of the vacuum degree, shorten the drainage path in deep soil layers, change the seepage direction in middle soil layers, and maintain a high vacuum degree in upper soil layers. Meanwhile, deep soil layers can be reinforced effectively, and the consolidation settlement tends to be more uniform. Moreover, this method can increase the effective reinforcement depth to a great extent and reduce the post-construction settlement to a certain degree.