Union Sanitary District (USD) manages 777 miles of sanitary sewer line, most of it 8-inch clay pipes. Clay pipe means a lot of root issues. “It only takes a 0.1 millimeter gap for a root to get started,” observes Andy Morrison, collection system manager.“At one time, roots were easily the biggest source of maintenance issues and generated the most service complaints. Thanks to a chemical root-control program that started in the early 1980s, roots are no longer the No.1 source of our stoppages. That honor now belongs to grease buildups.”Root control is just one initiative that has helped the district
