Responsa על בבא בתרא 11:13

Q. Some of the water from A's roofs used to drain into the Synagogue courtyard. Subsequently, A opened a spout, for the purpose of draining the water off his roof, which spout extended into the synagogue courtyard and thus all the water from A's roof was poured into the courtyard. The members of the community objected to this.
A. A must remove his spout.
SOURCES: Pr. 236.