The subsurface wastewater infiltration system is suitable for mall-scale municipal wastewater treatment utilizing natural purifying processes. It is a viable option for decentralized wastewater treatment in north-western drought regions of China with its advantages in low cost in investment and energy, and relatively robust efficiency.This paper, based on an experiment conducted in Xi'an, analyzed the performance and mechanism of such a system under various hydraulic loadings. The results are as follows:1. ...