Just days before the holidays, the city is warning thousands on Chicago’s South Side of a potential boil order for drinking and cooking water during a large water main repair this weekend.  The Chicago Department of Water Management said in a news release that it plans to begin repairs Saturday morning on a water main that serves the Beverly, Morgan Park and Auburn Gresham neighborhoods.  The department said it intends to “use every tactic available” to avoid issuing a boil order, but that there’s a “small chance” it becomes necessary. It said it will notify residents with updates via text alerts or calls.  The department issued a boil order in these neighborhoods about five months ago following a leak in a high-pressure water main at the more than a century-old Roseland Pumping Station. Ald. Matt O’Shea, 19th, said he spoke with Mayor Brandon Johnson’s Chief Operating Officer, John Roberson, and learned the city is ‘cautiously optimistic’ that a boil order can be avoided. O’Shea had earlier criticized the Johnson administration for not clearly communicating earlier with his office and affected residents. “Nothing is convenient when you’re talking about the weekend before Christmas. You’re talking about tens of thousands of residents impacted, hundreds of businesses.” the South Side alderman said. “But I would much rather be proactively working on this than something more serious.”