Resumo. The repeal of the Brazilian Forest Code, Law 4.771 (BRASIL, 1965), by the Law 12.651 (BRASIL, 2012b) generated great controversies in the country and brought important changes on various topics. In urban areas, it is essential the vision of new provisions concerning the establishment of Permanent Preservation Areas (PPAs), an important mechanism of environmental protection. In this article, the Law 12.651 (BRASIL, 2012b) was analyzed in relation to urban PPAs, emphasizing changes in relation to 1965 Forest Code, and introducing considerations about channeling and rectification of urban rivers. Some advances and setbacks were noticed in the new legislation as well as the need to control changes in watercourses within urban areas.