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In China, human schistosomiasis is caused by infection with the parasitic blood fluke Schistosoma japonicum, which requires snail hosts as a lifecycle intermediary. Snail control efforts have been a key component of China’s schistosomiasis control program, which has reduced human infections from 11 million in the 1950s to approximately 115,000 today. However, schistosomiasis has re-emerged in some areas, and the range of areas infested by or suitable for snail hosts is expanding. Understanding how the physical structure of the environment influences snail migration could aid in understanding how intermediate host mobility contributes to persistence and/or re-emergence of schistosomiasis. Within the 29 sites sampled for snail hosts, we estimated that between 14–33% of snails were recent migrants from another site, and above average inter-site migration rates occurred between sites separated by up to 44 km. Greater landscape connectivity was associated with increased recent migration rates. Connectivity models considering land use patterns explained the largest proportion of the variance in migration rates between sites. An increase in the number of irrigation channels leading into the site was associated with an increase in a site’s propensity to both attract migrant snails and retain snails. Our findings have important implications for understanding and responding to the geographic spread of schistosomiasis.