If you saw a sewer in a dream, then such dream warns you about emotions or people that has to be over. Make sure you clear out all of it or swap it with something different.
Dream dictionary: Sewer dream meanings
Violent fights.
…Pipes seen in dreams, are representatives of peace and comfort after many struggles. Sewer, gas, and such like pipes, denotes unusual thought and prosperity in your community. Old and broken pipe, signifies ill health and stagnation of business. Dreaming that you smoke a pipe, denotes that you will enjoy the visit of an old friend, and peaceful settlements of differences will also take place….
If you were sewing something or became a sewer, then it means that you are trying to make new relationships with others. It could also show something that you are trying to repair, therefore you use the needle and a cord or a sewing machine. Probably you are trying to make a new look towards something.