Irrigation and drainage scemes often result in many far-reaching environmental changes. Some benefit human while others threaten the sustainable development of the projects themselves. This paper takes example from the Hetao Irrigation District, the largest one along the Yellow River (1 million ha, Inner Mongolia, North china) and studies its environmental evolvement as the result of modern reclamation since early 70s to now and impacting the soil salinity and the receiving media which is the most important wetland in northwest china (namely Wuliangsuhai Lake). The changes in groundwater quality, soil salinisation, drainage water quality and the environment of the main water body are compared and analyzed. It shows that the development since 70s and the operation of the system have a close relation with the environmental evolvement and the reclamation has made a great impact on local environment. The salinization, which reached its peak in the late 80s, now trends to descend due to more sustainable drainage and irrigation management. But it is still severe and underlying salinisation risk still exists since salt is accumulating inside at various levels. The non-disposed drainage water has become to be the main pollution source and pushes the Wuliangsuhai Lake to a severe environmental crisis. The quality of groundwater is worsening and constitute an inducement to soil salinisation and threaten to human health. Further research in the tendency of the local environment evolvement and the relation between it and water-soil management needs to be performed especially in the duality context of the ongoing water saving and soil salinity control programmes and the respect of nation wide concerned wetlands.