Whilst the Indus Waters Treaty of 1960 allows for damning and infrastructural development in the Indus River Basin, it does so without factoring in environmental considerations. This is because environmental standards in international law, except those related to pollution control, were largely absent when the Treaty was negotiated in the 1950s. Given the increasing list of development-related disputes between India and Pakistan, and their aspirations for further damming and other infrastructural works in the Basin, this paper seeks to close the gaps in the Treaty’s provisions and developments in international environmental law to date. To do so effectively, the paper analyzes the relevant provisions of the UN Watercourses Convention, supplemented with an examination of the European regional framework. Based on these, it proposes changes to the Treaty so that both India and Pakistan are able to work within a legal framework which not only provides for environmental impact assessments for planned projects, but enhances monitoring, assessments, and reporting. This will ensure that such developments are not only environmentally sound but also help to alleviate some of the disputes between India and Pakistan.