The Ontario government is seeking to punt the question of what to do with millions of litres of Greater Toronto Area sewage to an expert panel. York Region, located north of Toronto, has sought for years to build a new sewage treatment plant to accommodate an anticipated 153,000 additional people in the suburbs of Aurora, Newmarket and East Gwillimbury. At issue is the question of whether that wastewater should flow into Lake Simcoe or Lake Ontario — or whether there’s an alternative that hasn’t yet been explored.