A water main break at Bergen and Communipaw avenues in Jersey City has left businesses and neighbors in the area with low pressure or no water at all, Suez offficials said. Crews from Suez, the company that operates the Jersey City water system, are conducting emergency repairs on a 20-inch main, spokesman Chris Halloran said. The affected area is Bergen Avenue between Communipaw and Brinkerhoff avenues. Crews were conducting a test shutdown overnight to plan for future repairs involving the main running along Bergen Avenue, near the corner of Communipaw. The subsequent failure of a valve on t…