Shops that discharge sewage into urban drainage facilities in residential areas shall apply for a permit to discharge sewage into the drainage pipe network according to law, and residential areas do not need to obtain a permit to discharge domestic sewage into the drainage pipe network.

The basis is Article 21 of the Regulations on Urban Drainage and Sewage Treatment: enterprises, institutions and individual industrial and commercial households engaged in industrial, construction, catering and medical activities that discharge sewage into urban drainage facilities shall apply to the competent department of urban drainage for a permit to discharge sewage into the drainage pipe network.