Who is responsible for the backflow of sewage on the first floor?

Legal analysis: Generally speaking, there are two kinds of public drainage systems in residential buildings, one is sewage pipe and the other is rainwater pipe. The daily dredging of sewage pipes is usually the responsibility of property management, which is written into the service contract signed between residents and property management. If the daily dredging of sewage pipes leads to sewage backflow, the responsibility of the property company should be investigated; If the sewage pipeline is blocked by other owners, you can choose to directly investigate the responsibility of other owners.

Legal basis: Article 288 of the Civil Law of People's Republic of China (PRC), the neighboring owners of real estate shall correctly handle the neighboring relationship according to the principles of being beneficial to production, convenient to life, solidarity and mutual assistance, and fairness and reasonableness.

Article 296 Where the owner of a realty uses an adjacent realty for water use, drainage, passage, pipeline laying, etc. We should try our best to avoid causing damage to neighboring real estate owners.